diff --git a/regtest/basic/rt-ttmetad0/COLVAR.reference b/regtest/basic/rt-ttmetad0/COLVAR.reference
new file mode 100644
index 0000000000000000000000000000000000000000..f5f2556ab461137d8d242a696c91e14557267441
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/COLVAR.reference
@@ -0,0 +1,24 @@
+#! FIELDS time psi phi metadnp1.bias metadnp2.bias metadp1.bias metadp2.bias metadnp1.transbias metadnp2.transbias metadp1.transbias metadp2.transbias
+#! SET min_phi -pi
+#! SET max_phi pi
+ 0.000000 1.9470 -1.2379 1.0000 1.0000 1.0000 1.0000 0.3000 0.5000 0.5000 0.5000
+ 1.000000 1.9381 -1.4839 1.0000 1.0000 1.0000 1.0000 0.5222 0.7222 0.5000 0.5000
+ 2.000000 1.9663 -1.3243 2.1717 2.1717 1.8174 1.8174 0.6919 0.8919 0.5000 0.5000
+ 3.000000 1.9885 -1.3340 3.3068 3.3068 3.0396 3.0396 0.8275 1.0000 0.5000 0.5000
+ 4.000000 1.8901 -1.4613 4.3446 4.3446 4.0274 4.0274 1.0000 1.0000 0.5000 0.5000
+ 5.000000 2.0306 -1.2202 5.2323 5.2323 4.1876 4.1876 1.0000 1.0000 0.5000 0.5000
+ 6.000000 1.8776 -1.3883 6.3558 6.3561 6.1873 6.1873 1.0000 1.0000 0.5000 0.5000
+ 7.000000 1.9488 -1.5481 7.8785 7.8785 5.7970 5.7970 1.0000 1.0000 0.5000 0.5000
+ 8.000000 1.9025 -1.8429 8.9398 8.9398 2.0540 2.0540 1.0000 1.0000 0.5000 0.5044
+ 9.000000 1.9813 -2.2424 10.0108 10.0108 0.7885 0.9091 1.0000 1.0000 0.7841 0.9841
+ 10.000000 1.9684 -1.1482 11.2936 11.2936 5.4476 5.4476 1.0000 1.0000 0.7841 0.9841
+ 11.000000 1.9807 -1.7580 12.3590 12.3590 4.4087 4.4087 1.0000 1.0000 0.7841 0.9841
+ 12.000000 1.9486 -1.3186 13.7391 13.7391 8.9183 8.9183 1.0000 1.0000 0.7841 0.9841
+ 13.000000 1.9547 -2.9911 14.9056 14.9056 0.8777 0.9067 1.0000 1.0000 0.8532 1.0000
+ 14.000000 2.0415 -1.4112 14.5576 14.5576 10.2914 10.2914 1.0000 1.0000 0.8532 1.0000
+ 15.000000 1.9166 -2.5995 16.9774 16.9774 0.7817 0.9715 1.0000 1.0000 1.0000 1.0000
+ 16.000000 1.9433 -1.4608 18.3468 18.3468 11.0623 11.0623 1.0000 1.0000 1.0000 1.0000
+ 17.000000 2.0625 -1.3791 16.9507 16.9507 12.4108 12.4108 1.0000 1.0000 1.0000 1.0000
+ 18.000000 1.9433 -1.6771 20.5250 20.5250 8.6582 8.6582 1.0000 1.0000 1.0000 1.0000
+ 19.000000 1.9642 -1.5241 21.6666 21.6666 12.8577 12.8577 1.0000 1.0000 1.0000 1.0000
+ 20.000000 1.9296 -1.1997 22.8027 22.8027 10.8895 10.8895 1.0000 1.0000 1.0000 1.0000
diff --git a/regtest/basic/rt-ttmetad0/HILLS-nonperiodic-case1.reference b/regtest/basic/rt-ttmetad0/HILLS-nonperiodic-case1.reference
new file mode 100644
index 0000000000000000000000000000000000000000..fefd564be6d4024dbd430ec06a4893ee89b619a9
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/HILLS-nonperiodic-case1.reference
@@ -0,0 +1,22 @@
+#! FIELDS time psi sigma_psi height biasf
+#! SET multivariate false
+ 1 1.938132764982607 0.2 1.2 -1
+ 2 1.966349061093571 0.2 1.2 -1
+ 3 1.988460591924974 0.2 1.2 -1
+ 4 1.890108457957857 0.2 1.2 -1
+ 5 2.030630313314516 0.2 1.2 -1
+ 6 1.877631741588439 0.2 1.2 -1
+ 7 1.9487542529822 0.2 1.2 -1
+ 8 1.902457857730782 0.2 1.2 -1
+ 9 1.981347055320541 0.2 1.2 -1
+ 10 1.968444216110897 0.2 1.2 -1
+ 11 1.980702405742474 0.2 1.2 -1
+ 12 1.948618696187008 0.2 1.2 -1
+ 13 1.954734059705066 0.2 1.2 -1
+ 14 2.041520579428038 0.2 1.2 -1
+ 15 1.916576972544074 0.2 1.2 -1
+ 16 1.94328347326306 0.2 1.2 -1
+ 17 2.062462992805603 0.2 1.2 -1
+ 18 1.943260862166429 0.2 1.2 -1
+ 19 1.964159206212332 0.2 1.2 -1
+ 20 1.929638968944854 0.2 1.2 -1
diff --git a/regtest/basic/rt-ttmetad0/HILLS-nonperiodic-case2.reference b/regtest/basic/rt-ttmetad0/HILLS-nonperiodic-case2.reference
new file mode 100644
index 0000000000000000000000000000000000000000..fefd564be6d4024dbd430ec06a4893ee89b619a9
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/HILLS-nonperiodic-case2.reference
@@ -0,0 +1,22 @@
+#! FIELDS time psi sigma_psi height biasf
+#! SET multivariate false
+ 1 1.938132764982607 0.2 1.2 -1
+ 2 1.966349061093571 0.2 1.2 -1
+ 3 1.988460591924974 0.2 1.2 -1
+ 4 1.890108457957857 0.2 1.2 -1
+ 5 2.030630313314516 0.2 1.2 -1
+ 6 1.877631741588439 0.2 1.2 -1
+ 7 1.9487542529822 0.2 1.2 -1
+ 8 1.902457857730782 0.2 1.2 -1
+ 9 1.981347055320541 0.2 1.2 -1
+ 10 1.968444216110897 0.2 1.2 -1
+ 11 1.980702405742474 0.2 1.2 -1
+ 12 1.948618696187008 0.2 1.2 -1
+ 13 1.954734059705066 0.2 1.2 -1
+ 14 2.041520579428038 0.2 1.2 -1
+ 15 1.916576972544074 0.2 1.2 -1
+ 16 1.94328347326306 0.2 1.2 -1
+ 17 2.062462992805603 0.2 1.2 -1
+ 18 1.943260862166429 0.2 1.2 -1
+ 19 1.964159206212332 0.2 1.2 -1
+ 20 1.929638968944854 0.2 1.2 -1
diff --git a/regtest/basic/rt-ttmetad0/HILLS-periodic-case1.reference b/regtest/basic/rt-ttmetad0/HILLS-periodic-case1.reference
new file mode 100644
index 0000000000000000000000000000000000000000..a14519b7df242fb807c8fa9ea9e5c41b99030d9d
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/HILLS-periodic-case1.reference
@@ -0,0 +1,24 @@
+#! FIELDS time phi sigma_phi height biasf
+#! SET multivariate false
+#! SET min_phi -pi
+#! SET max_phi pi
+ 1 -1.483864797032211 0.2 1.2 -1
+ 2 -1.324349464027241 0.2 1.2 -1
+ 3 -1.334014372833683 0.2 1.2 -1
+ 4 -1.461334733547937 0.2 1.2 -1
+ 5 -1.220227832598179 0.2 1.2 -1
+ 6 -1.388275748836901 0.2 1.2 -1
+ 7 -1.548083770068421 0.2 1.2 -1
+ 8 -1.842857738569458 0.2 1.2 -1
+ 9 -2.242442614461024 0.2 1.2 -1
+ 10 -1.148221252978592 0.2 1.2 -1
+ 11 -1.757993684553651 0.2 1.2 -1
+ 12 -1.318567054245503 0.2 1.2 -1
+ 13 -2.991104158561357 0.2 1.2 -1
+ 14 -1.411190277910799 0.2 1.2 -1
+ 15 -2.59947290674873 0.2 1.2 -1
+ 16 -1.460820764733805 0.2 1.2 -1
+ 17 -1.379146894998496 0.2 1.2 -1
+ 18 -1.677124361971585 0.2 1.2 -1
+ 19 -1.524070841192655 0.2 1.2 -1
+ 20 -1.199652274777625 0.2 1.2 -1
diff --git a/regtest/basic/rt-ttmetad0/HILLS-periodic-case2.reference b/regtest/basic/rt-ttmetad0/HILLS-periodic-case2.reference
new file mode 100644
index 0000000000000000000000000000000000000000..a14519b7df242fb807c8fa9ea9e5c41b99030d9d
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/HILLS-periodic-case2.reference
@@ -0,0 +1,24 @@
+#! FIELDS time phi sigma_phi height biasf
+#! SET multivariate false
+#! SET min_phi -pi
+#! SET max_phi pi
+ 1 -1.483864797032211 0.2 1.2 -1
+ 2 -1.324349464027241 0.2 1.2 -1
+ 3 -1.334014372833683 0.2 1.2 -1
+ 4 -1.461334733547937 0.2 1.2 -1
+ 5 -1.220227832598179 0.2 1.2 -1
+ 6 -1.388275748836901 0.2 1.2 -1
+ 7 -1.548083770068421 0.2 1.2 -1
+ 8 -1.842857738569458 0.2 1.2 -1
+ 9 -2.242442614461024 0.2 1.2 -1
+ 10 -1.148221252978592 0.2 1.2 -1
+ 11 -1.757993684553651 0.2 1.2 -1
+ 12 -1.318567054245503 0.2 1.2 -1
+ 13 -2.991104158561357 0.2 1.2 -1
+ 14 -1.411190277910799 0.2 1.2 -1
+ 15 -2.59947290674873 0.2 1.2 -1
+ 16 -1.460820764733805 0.2 1.2 -1
+ 17 -1.379146894998496 0.2 1.2 -1
+ 18 -1.677124361971585 0.2 1.2 -1
+ 19 -1.524070841192655 0.2 1.2 -1
+ 20 -1.199652274777625 0.2 1.2 -1
diff --git a/regtest/basic/rt-ttmetad0/Makefile b/regtest/basic/rt-ttmetad0/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..3703b27cea227aa053fb6d1d73f861e4384dbcee
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/Makefile
@@ -0,0 +1 @@
+include ../../scripts/test.make
diff --git a/regtest/basic/rt-ttmetad0/config b/regtest/basic/rt-ttmetad0/config
new file mode 100644
index 0000000000000000000000000000000000000000..ce858d0c5a1fc8ff0fa3f73d5836edaf432c82e8
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/config
@@ -0,0 +1,3 @@
+type=driver
+# this is to test a different name
+arg="--plumed plumed.dat --trajectory-stride 500 --timestep 0.002 --igro traj.gro"
diff --git a/regtest/basic/rt-ttmetad0/grid-nonperiodic-case1 b/regtest/basic/rt-ttmetad0/grid-nonperiodic-case1
new file mode 100644
index 0000000000000000000000000000000000000000..40821efbfa733fccb00d6d7735fb6e89df469a87
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/grid-nonperiodic-case1
@@ -0,0 +1,16 @@
+#! FIELDS psi metadnp1.bias der_psi
+#! SET min_psi 0
+#! SET max_psi pi
+#! SET nbins_psi 11
+#! SET periodic_psi false
+ 0.000000000 1.00000 0.00000
+ 0.314159265 0.50000 0.00000
+ 0.628318531 1.00000 0.00000
+ 0.942477796 1.00000 0.00000
+ 1.256637061 1.00000 0.00000
+ 1.570796327 0.30000 0.00000
+ 1.884955592 1.00000 0.00000
+ 2.199114858 1.00000 0.00000
+ 2.513274123 1.00000 0.00000
+ 2.827433388 1.00000 0.00000
+ 3.141592654 1.00000 0.00000
diff --git a/regtest/basic/rt-ttmetad0/grid-nonperiodic-case2 b/regtest/basic/rt-ttmetad0/grid-nonperiodic-case2
new file mode 100644
index 0000000000000000000000000000000000000000..8f3306d99fbfee7d9ff4755ce7a592fbdfe13777
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/grid-nonperiodic-case2
@@ -0,0 +1,16 @@
+#! FIELDS psi metadnp2.bias der_psi
+#! SET min_psi 0
+#! SET max_psi pi
+#! SET nbins_psi 11
+#! SET periodic_psi false
+ 0.000000000 1.00000 0.00000
+ 0.314159265 0.30000 0.00000
+ 0.628318531 1.00000 0.00000
+ 0.942477796 1.00000 0.00000
+ 1.256637061 1.00000 0.00000
+ 1.570796327 0.50000 0.00000
+ 1.884955592 1.00000 0.00000
+ 2.199114858 1.00000 0.00000
+ 2.513274123 1.00000 0.00000
+ 2.827433388 1.00000 0.00000
+ 3.141592654 1.00000 0.00000
diff --git a/regtest/basic/rt-ttmetad0/grid-periodic-case1 b/regtest/basic/rt-ttmetad0/grid-periodic-case1
new file mode 100644
index 0000000000000000000000000000000000000000..4334afe9c247cba056027107b938c4519175af8d
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/grid-periodic-case1
@@ -0,0 +1,15 @@
+#! FIELDS phi metadp1.bias der_phi
+#! SET min_phi -pi
+#! SET max_phi pi
+#! SET nbins_phi 10
+#! SET periodic_phi true
+ -3.141592654 1.000000 0.000000
+ -2.513274123 0.300000 0.000000
+ -1.884955592 1.000000 0.000000
+ -1.256637061 1.000000 0.000000
+ -0.628318531 1.000000 0.000000
+ 0.000000000 0.500000 0.000000
+ 0.628318531 1.000000 0.000000
+ 1.256637061 1.000000 0.000000
+ 1.884955592 1.000000 0.000000
+ 2.513274123 1.000000 0.000000
diff --git a/regtest/basic/rt-ttmetad0/grid-periodic-case2 b/regtest/basic/rt-ttmetad0/grid-periodic-case2
new file mode 100644
index 0000000000000000000000000000000000000000..b83a0f6186c04774fc35b9e0cdcac8ba3a5359ac
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/grid-periodic-case2
@@ -0,0 +1,15 @@
+#! FIELDS phi metadp2.bias der_phi
+#! SET min_phi -pi
+#! SET max_phi pi
+#! SET nbins_phi 10
+#! SET periodic_phi true
+ -3.141592654 1.000000 0.000000
+ -2.513274123 0.500000 0.000000
+ -1.884955592 1.000000 0.000000
+ -1.256637061 1.000000 0.000000
+ -0.628318531 1.000000 0.000000
+ 0.000000000 0.300000 0.000000
+ 0.628318531 1.000000 0.000000
+ 1.256637061 1.000000 0.000000
+ 1.884955592 1.000000 0.000000
+ 2.513274123 1.000000 0.000000
diff --git a/regtest/basic/rt-ttmetad0/plumed.dat b/regtest/basic/rt-ttmetad0/plumed.dat
new file mode 100644
index 0000000000000000000000000000000000000000..76d19f0626acca166cd44dd5f342d25a820e3f9d
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/plumed.dat
@@ -0,0 +1,79 @@
+RESTART
+
+psi: ANGLE ATOMS=7,9,15
+phi: TORSION ATOMS=5,7,9,15 NOPBC
+
+METAD ...
+ LABEL=metadnp1
+ ARG=psi
+ SIGMA=0.20
+ HEIGHT=1.20
+ CALC_TRANSITION_BIAS
+ TRANSITIONWELL0=1.0
+ TRANSITIONWELL1=2.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS-nonperiodic-case1
+ GRID_RFILE=grid-nonperiodic-case1
+ GRID_MIN=0
+ GRID_MAX=pi
+ GRID_BIN=10
+... METAD
+
+METAD ...
+ LABEL=metadnp2
+ ARG=psi
+ SIGMA=0.20
+ HEIGHT=1.20
+ CALC_TRANSITION_BIAS
+ TRANSITIONWELL0=1.0
+ TRANSITIONWELL1=2.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS-nonperiodic-case2
+ GRID_RFILE=grid-nonperiodic-case2
+ GRID_MIN=0
+ GRID_MAX=pi
+ GRID_BIN=10
+... METAD
+
+METAD ...
+ LABEL=metadp1
+ ARG=phi
+ SIGMA=0.20
+ HEIGHT=1.20
+ CALC_TRANSITION_BIAS
+ TRANSITIONWELL0=-1.0
+ TRANSITIONWELL1=1.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS-periodic-case1
+ GRID_RFILE=grid-periodic-case1
+ GRID_MIN=-pi
+ GRID_MAX=pi
+ GRID_BIN=10
+... METAD
+
+METAD ...
+ LABEL=metadp2
+ ARG=phi
+ SIGMA=0.20
+ HEIGHT=1.20
+ CALC_TRANSITION_BIAS
+ TRANSITIONWELL0=-1.0
+ TRANSITIONWELL1=1.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS-periodic-case2
+ GRID_RFILE=grid-periodic-case2
+ GRID_MIN=-pi
+ GRID_MAX=pi
+ GRID_BIN=10
+... METAD
+
+PRINT ...
+ ARG=psi,phi,metadnp1.bias,metadnp2.bias,metadp1.bias,metadp2.bias,metadnp1.transbias,metadnp2.transbias,metadp1.transbias,metadp2.transbias
+ STRIDE=500
+ FILE=COLVAR
+ FMT=%8.4f
+... PRINT
diff --git a/regtest/basic/rt-ttmetad0/traj.gro b/regtest/basic/rt-ttmetad0/traj.gro
new file mode 100644
index 0000000000000000000000000000000000000000..c1c387a0144ec8021b9e5b0453be534f2ca906e2
--- /dev/null
+++ b/regtest/basic/rt-ttmetad0/traj.gro
@@ -0,0 +1,525 @@
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 0.00000
+ 22
+ 1ACE HH31 1 1.474 1.585 1.200
+ 1ACE CH3 2 1.483 1.508 1.277
+ 1ACE HH32 3 1.476 1.561 1.372
+ 1ACE HH33 4 1.578 1.455 1.278
+ 1ACE C 5 1.353 1.428 1.279
+ 1ACE O 6 1.263 1.449 1.357
+ 2ALA N 7 1.343 1.328 1.191
+ 2ALA H 8 1.415 1.321 1.120
+ 2ALA CA 9 1.233 1.239 1.159
+ 2ALA HA 10 1.144 1.302 1.155
+ 2ALA CB 11 1.244 1.182 1.013
+ 2ALA HB1 12 1.341 1.136 0.992
+ 2ALA HB2 13 1.159 1.117 0.994
+ 2ALA HB3 14 1.242 1.265 0.942
+ 2ALA C 15 1.207 1.140 1.271
+ 2ALA O 16 1.214 1.017 1.241
+ 3NME N 17 1.191 1.177 1.398
+ 3NME H 18 1.192 1.275 1.421
+ 3NME CH3 19 1.189 1.086 1.518
+ 3NME HH31 20 1.170 0.983 1.487
+ 3NME HH32 21 1.283 1.087 1.574
+ 3NME HH33 22 1.108 1.127 1.578
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 1.00000
+ 22
+ 1ACE HH31 1 1.480 1.571 1.214
+ 1ACE CH3 2 1.481 1.493 1.289
+ 1ACE HH32 3 1.502 1.528 1.390
+ 1ACE HH33 4 1.551 1.417 1.255
+ 1ACE C 5 1.344 1.432 1.275
+ 1ACE O 6 1.250 1.462 1.345
+ 2ALA N 7 1.342 1.327 1.193
+ 2ALA H 8 1.430 1.313 1.144
+ 2ALA CA 9 1.233 1.244 1.166
+ 2ALA HA 10 1.144 1.307 1.173
+ 2ALA CB 11 1.240 1.189 1.017
+ 2ALA HB1 12 1.327 1.124 1.000
+ 2ALA HB2 13 1.150 1.128 1.005
+ 2ALA HB3 14 1.251 1.267 0.941
+ 2ALA C 15 1.221 1.133 1.271
+ 2ALA O 16 1.217 1.015 1.238
+ 3NME N 17 1.204 1.174 1.395
+ 3NME H 18 1.200 1.275 1.398
+ 3NME CH3 19 1.188 1.089 1.516
+ 3NME HH31 20 1.083 1.086 1.543
+ 3NME HH32 21 1.233 0.990 1.511
+ 3NME HH33 22 1.241 1.141 1.596
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 2.00000
+ 22
+ 1ACE HH31 1 1.532 1.520 1.209
+ 1ACE CH3 2 1.478 1.493 1.300
+ 1ACE HH32 3 1.465 1.586 1.356
+ 1ACE HH33 4 1.548 1.426 1.350
+ 1ACE C 5 1.352 1.423 1.279
+ 1ACE O 6 1.252 1.461 1.340
+ 2ALA N 7 1.351 1.326 1.190
+ 2ALA H 8 1.442 1.293 1.160
+ 2ALA CA 9 1.232 1.244 1.160
+ 2ALA HA 10 1.146 1.310 1.151
+ 2ALA CB 11 1.241 1.190 1.016
+ 2ALA HB1 12 1.333 1.132 1.008
+ 2ALA HB2 13 1.160 1.123 0.986
+ 2ALA HB3 14 1.242 1.280 0.955
+ 2ALA C 15 1.203 1.138 1.270
+ 2ALA O 16 1.161 1.021 1.240
+ 3NME N 17 1.230 1.171 1.396
+ 3NME H 18 1.257 1.266 1.417
+ 3NME CH3 19 1.217 1.090 1.512
+ 3NME HH31 20 1.144 1.011 1.493
+ 3NME HH32 21 1.307 1.029 1.526
+ 3NME HH33 22 1.212 1.146 1.605
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 3.00000
+ 22
+ 1ACE HH31 1 1.439 1.582 1.175
+ 1ACE CH3 2 1.474 1.516 1.254
+ 1ACE HH32 3 1.480 1.585 1.338
+ 1ACE HH33 4 1.569 1.465 1.242
+ 1ACE C 5 1.364 1.419 1.280
+ 1ACE O 6 1.277 1.446 1.367
+ 2ALA N 7 1.358 1.323 1.194
+ 2ALA H 8 1.443 1.313 1.140
+ 2ALA CA 9 1.235 1.243 1.164
+ 2ALA HA 10 1.150 1.310 1.170
+ 2ALA CB 11 1.240 1.197 1.019
+ 2ALA HB1 12 1.316 1.119 1.016
+ 2ALA HB2 13 1.145 1.157 0.982
+ 2ALA HB3 14 1.279 1.276 0.955
+ 2ALA C 15 1.201 1.137 1.272
+ 2ALA O 16 1.172 1.021 1.232
+ 3NME N 17 1.218 1.166 1.402
+ 3NME H 18 1.240 1.259 1.434
+ 3NME CH3 19 1.186 1.086 1.518
+ 3NME HH31 20 1.225 0.984 1.527
+ 3NME HH32 21 1.193 1.134 1.616
+ 3NME HH33 22 1.081 1.058 1.509
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 4.00000
+ 22
+ 1ACE HH31 1 1.549 1.508 1.196
+ 1ACE CH3 2 1.500 1.486 1.290
+ 1ACE HH32 3 1.487 1.571 1.357
+ 1ACE HH33 4 1.563 1.415 1.343
+ 1ACE C 5 1.362 1.425 1.270
+ 1ACE O 6 1.265 1.465 1.340
+ 2ALA N 7 1.349 1.324 1.182
+ 2ALA H 8 1.432 1.287 1.138
+ 2ALA CA 9 1.221 1.249 1.168
+ 2ALA HA 10 1.138 1.318 1.184
+ 2ALA CB 11 1.201 1.194 1.025
+ 2ALA HB1 12 1.276 1.117 1.005
+ 2ALA HB2 13 1.096 1.165 1.014
+ 2ALA HB3 14 1.229 1.265 0.947
+ 2ALA C 15 1.217 1.141 1.275
+ 2ALA O 16 1.234 1.024 1.243
+ 3NME N 17 1.183 1.174 1.400
+ 3NME H 18 1.184 1.274 1.412
+ 3NME CH3 19 1.187 1.078 1.509
+ 3NME HH31 20 1.248 0.990 1.490
+ 3NME HH32 21 1.220 1.120 1.604
+ 3NME HH33 22 1.088 1.035 1.527
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 5.00000
+ 22
+ 1ACE HH31 1 1.449 1.585 1.168
+ 1ACE CH3 2 1.479 1.518 1.248
+ 1ACE HH32 3 1.523 1.577 1.328
+ 1ACE HH33 4 1.565 1.461 1.213
+ 1ACE C 5 1.364 1.422 1.284
+ 1ACE O 6 1.305 1.438 1.389
+ 2ALA N 7 1.347 1.326 1.187
+ 2ALA H 8 1.423 1.328 1.122
+ 2ALA CA 9 1.226 1.241 1.162
+ 2ALA HA 10 1.139 1.308 1.162
+ 2ALA CB 11 1.236 1.193 1.023
+ 2ALA HB1 12 1.314 1.117 1.012
+ 2ALA HB2 13 1.137 1.167 0.986
+ 2ALA HB3 14 1.273 1.278 0.966
+ 2ALA C 15 1.195 1.133 1.268
+ 2ALA O 16 1.173 1.016 1.239
+ 3NME N 17 1.204 1.175 1.393
+ 3NME H 18 1.211 1.275 1.403
+ 3NME CH3 19 1.188 1.090 1.513
+ 3NME HH31 20 1.089 1.044 1.509
+ 3NME HH32 21 1.267 1.014 1.509
+ 3NME HH33 22 1.189 1.145 1.607
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 6.00000
+ 22
+ 1ACE HH31 1 1.517 1.511 1.181
+ 1ACE CH3 2 1.490 1.488 1.284
+ 1ACE HH32 3 1.482 1.582 1.339
+ 1ACE HH33 4 1.569 1.421 1.316
+ 1ACE C 5 1.359 1.414 1.282
+ 1ACE O 6 1.272 1.447 1.358
+ 2ALA N 7 1.351 1.320 1.186
+ 2ALA H 8 1.434 1.297 1.133
+ 2ALA CA 9 1.220 1.251 1.159
+ 2ALA HA 10 1.139 1.323 1.167
+ 2ALA CB 11 1.220 1.194 1.018
+ 2ALA HB1 12 1.298 1.120 1.003
+ 2ALA HB2 13 1.120 1.158 0.994
+ 2ALA HB3 14 1.224 1.286 0.960
+ 2ALA C 15 1.201 1.139 1.270
+ 2ALA O 16 1.190 1.022 1.239
+ 3NME N 17 1.203 1.178 1.393
+ 3NME H 18 1.207 1.277 1.409
+ 3NME CH3 19 1.211 1.102 1.515
+ 3NME HH31 20 1.111 1.064 1.534
+ 3NME HH32 21 1.275 1.017 1.492
+ 3NME HH33 22 1.264 1.151 1.597
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 7.00000
+ 22
+ 1ACE HH31 1 1.483 1.590 1.185
+ 1ACE CH3 2 1.505 1.501 1.245
+ 1ACE HH32 3 1.538 1.533 1.344
+ 1ACE HH33 4 1.580 1.430 1.209
+ 1ACE C 5 1.379 1.418 1.267
+ 1ACE O 6 1.298 1.443 1.349
+ 2ALA N 7 1.360 1.320 1.187
+ 2ALA H 8 1.426 1.297 1.114
+ 2ALA CA 9 1.224 1.253 1.180
+ 2ALA HA 10 1.147 1.326 1.205
+ 2ALA CB 11 1.174 1.215 1.037
+ 2ALA HB1 12 1.245 1.152 0.983
+ 2ALA HB2 13 1.084 1.154 1.032
+ 2ALA HB3 14 1.153 1.311 0.992
+ 2ALA C 15 1.212 1.141 1.280
+ 2ALA O 16 1.219 1.022 1.244
+ 3NME N 17 1.191 1.176 1.408
+ 3NME H 18 1.207 1.275 1.423
+ 3NME CH3 19 1.162 1.068 1.509
+ 3NME HH31 20 1.229 0.982 1.503
+ 3NME HH32 21 1.162 1.109 1.610
+ 3NME HH33 22 1.056 1.044 1.499
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 8.00000
+ 22
+ 1ACE HH31 1 1.576 1.425 1.169
+ 1ACE CH3 2 1.523 1.455 1.260
+ 1ACE HH32 3 1.547 1.556 1.294
+ 1ACE HH33 4 1.566 1.393 1.338
+ 1ACE C 5 1.385 1.422 1.255
+ 1ACE O 6 1.308 1.499 1.305
+ 2ALA N 7 1.346 1.311 1.189
+ 2ALA H 8 1.419 1.248 1.159
+ 2ALA CA 9 1.210 1.260 1.193
+ 2ALA HA 10 1.139 1.326 1.242
+ 2ALA CB 11 1.152 1.252 1.051
+ 2ALA HB1 12 1.230 1.210 0.987
+ 2ALA HB2 13 1.066 1.185 1.052
+ 2ALA HB3 14 1.127 1.354 1.024
+ 2ALA C 15 1.206 1.136 1.282
+ 2ALA O 16 1.195 1.023 1.229
+ 3NME N 17 1.210 1.152 1.420
+ 3NME H 18 1.221 1.243 1.463
+ 3NME CH3 19 1.185 1.048 1.518
+ 3NME HH31 20 1.195 0.948 1.475
+ 3NME HH32 21 1.261 1.070 1.593
+ 3NME HH33 22 1.088 1.064 1.565
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 9.00000
+ 22
+ 1ACE HH31 1 1.515 1.474 1.040
+ 1ACE CH3 2 1.535 1.461 1.147
+ 1ACE HH32 3 1.561 1.560 1.184
+ 1ACE HH33 4 1.612 1.386 1.165
+ 1ACE C 5 1.406 1.430 1.217
+ 1ACE O 6 1.361 1.502 1.307
+ 2ALA N 7 1.345 1.316 1.190
+ 2ALA H 8 1.384 1.254 1.121
+ 2ALA CA 9 1.217 1.277 1.242
+ 2ALA HA 10 1.187 1.348 1.319
+ 2ALA CB 11 1.111 1.278 1.134
+ 2ALA HB1 12 1.129 1.198 1.062
+ 2ALA HB2 13 1.018 1.269 1.189
+ 2ALA HB3 14 1.121 1.372 1.079
+ 2ALA C 15 1.217 1.133 1.309
+ 2ALA O 16 1.293 1.044 1.265
+ 3NME N 17 1.132 1.116 1.408
+ 3NME H 18 1.076 1.195 1.437
+ 3NME CH3 19 1.112 1.003 1.490
+ 3NME HH31 20 1.156 0.910 1.456
+ 3NME HH32 21 1.153 1.026 1.588
+ 3NME HH33 22 1.005 0.985 1.500
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 10.00000
+ 22
+ 1ACE HH31 1 1.536 1.485 1.135
+ 1ACE CH3 2 1.521 1.460 1.240
+ 1ACE HH32 3 1.528 1.557 1.289
+ 1ACE HH33 4 1.602 1.397 1.276
+ 1ACE C 5 1.385 1.401 1.261
+ 1ACE O 6 1.341 1.416 1.373
+ 2ALA N 7 1.322 1.332 1.167
+ 2ALA H 8 1.364 1.316 1.076
+ 2ALA CA 9 1.190 1.273 1.177
+ 2ALA HA 10 1.125 1.352 1.216
+ 2ALA CB 11 1.134 1.230 1.038
+ 2ALA HB1 12 1.167 1.128 1.016
+ 2ALA HB2 13 1.026 1.238 1.046
+ 2ALA HB3 14 1.174 1.287 0.953
+ 2ALA C 15 1.183 1.157 1.283
+ 2ALA O 16 1.111 1.061 1.259
+ 3NME N 17 1.264 1.157 1.396
+ 3NME H 18 1.320 1.241 1.405
+ 3NME CH3 19 1.264 1.070 1.510
+ 3NME HH31 20 1.163 1.057 1.548
+ 3NME HH32 21 1.311 0.974 1.487
+ 3NME HH33 22 1.326 1.109 1.592
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 11.00000
+ 22
+ 1ACE HH31 1 1.607 1.359 1.178
+ 1ACE CH3 2 1.535 1.442 1.176
+ 1ACE HH32 3 1.521 1.470 1.072
+ 1ACE HH33 4 1.569 1.533 1.224
+ 1ACE C 5 1.402 1.412 1.242
+ 1ACE O 6 1.368 1.454 1.350
+ 2ALA N 7 1.319 1.332 1.177
+ 2ALA H 8 1.363 1.279 1.103
+ 2ALA CA 9 1.194 1.289 1.231
+ 2ALA HA 10 1.153 1.355 1.308
+ 2ALA CB 11 1.092 1.300 1.113
+ 2ALA HB1 12 1.137 1.243 1.032
+ 2ALA HB2 13 1.001 1.243 1.131
+ 2ALA HB3 14 1.070 1.405 1.095
+ 2ALA C 15 1.198 1.143 1.290
+ 2ALA O 16 1.237 1.057 1.213
+ 3NME N 17 1.171 1.126 1.422
+ 3NME H 18 1.164 1.213 1.472
+ 3NME CH3 19 1.200 1.009 1.496
+ 3NME HH31 20 1.118 0.938 1.493
+ 3NME HH32 21 1.284 0.953 1.454
+ 3NME HH33 22 1.230 1.031 1.598
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 12.00000
+ 22
+ 1ACE HH31 1 1.491 1.569 1.138
+ 1ACE CH3 2 1.511 1.462 1.134
+ 1ACE HH32 3 1.614 1.449 1.166
+ 1ACE HH33 4 1.495 1.444 1.028
+ 1ACE C 5 1.416 1.394 1.229
+ 1ACE O 6 1.445 1.392 1.345
+ 2ALA N 7 1.299 1.357 1.181
+ 2ALA H 8 1.278 1.358 1.082
+ 2ALA CA 9 1.196 1.301 1.267
+ 2ALA HA 10 1.185 1.364 1.355
+ 2ALA CB 11 1.063 1.319 1.182
+ 2ALA HB1 12 1.057 1.248 1.100
+ 2ALA HB2 13 0.976 1.288 1.240
+ 2ALA HB3 14 1.037 1.423 1.161
+ 2ALA C 15 1.226 1.161 1.304
+ 2ALA O 16 1.317 1.094 1.258
+ 3NME N 17 1.135 1.110 1.387
+ 3NME H 18 1.064 1.174 1.419
+ 3NME CH3 19 1.121 0.972 1.429
+ 3NME HH31 20 1.163 0.900 1.358
+ 3NME HH32 21 1.177 0.954 1.520
+ 3NME HH33 22 1.016 0.942 1.428
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 13.00000
+ 22
+ 1ACE HH31 1 1.528 1.537 1.077
+ 1ACE CH3 2 1.543 1.448 1.137
+ 1ACE HH32 3 1.634 1.463 1.195
+ 1ACE HH33 4 1.560 1.362 1.072
+ 1ACE C 5 1.421 1.428 1.229
+ 1ACE O 6 1.396 1.520 1.301
+ 2ALA N 7 1.355 1.314 1.219
+ 2ALA H 8 1.385 1.241 1.156
+ 2ALA CA 9 1.249 1.276 1.311
+ 2ALA HA 10 1.297 1.288 1.409
+ 2ALA CB 11 1.122 1.359 1.284
+ 2ALA HB1 12 1.072 1.325 1.193
+ 2ALA HB2 13 1.053 1.352 1.367
+ 2ALA HB3 14 1.153 1.463 1.275
+ 2ALA C 15 1.204 1.131 1.290
+ 2ALA O 16 1.225 1.070 1.185
+ 3NME N 17 1.131 1.077 1.382
+ 3NME H 18 1.104 1.132 1.463
+ 3NME CH3 19 1.083 0.939 1.380
+ 3NME HH31 20 1.012 0.925 1.298
+ 3NME HH32 21 1.168 0.871 1.372
+ 3NME HH33 22 1.036 0.915 1.475
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 14.00000
+ 22
+ 1ACE HH31 1 1.543 1.468 1.123
+ 1ACE CH3 2 1.548 1.443 1.229
+ 1ACE HH32 3 1.566 1.540 1.276
+ 1ACE HH33 4 1.634 1.382 1.257
+ 1ACE C 5 1.420 1.385 1.285
+ 1ACE O 6 1.412 1.375 1.404
+ 2ALA N 7 1.324 1.361 1.200
+ 2ALA H 8 1.345 1.354 1.101
+ 2ALA CA 9 1.189 1.323 1.244
+ 2ALA HA 10 1.163 1.394 1.323
+ 2ALA CB 11 1.094 1.344 1.125
+ 2ALA HB1 12 1.098 1.270 1.045
+ 2ALA HB2 13 0.995 1.352 1.170
+ 2ALA HB3 14 1.120 1.440 1.079
+ 2ALA C 15 1.166 1.169 1.284
+ 2ALA O 16 1.055 1.145 1.330
+ 3NME N 17 1.263 1.077 1.279
+ 3NME H 18 1.356 1.102 1.247
+ 3NME CH3 19 1.246 0.942 1.335
+ 3NME HH31 20 1.142 0.911 1.345
+ 3NME HH32 21 1.293 0.868 1.270
+ 3NME HH33 22 1.292 0.934 1.434
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 15.00000
+ 22
+ 1ACE HH31 1 1.508 1.417 1.043
+ 1ACE CH3 2 1.539 1.448 1.143
+ 1ACE HH32 3 1.565 1.553 1.146
+ 1ACE HH33 4 1.630 1.395 1.169
+ 1ACE C 5 1.438 1.410 1.253
+ 1ACE O 6 1.429 1.471 1.356
+ 2ALA N 7 1.348 1.327 1.217
+ 2ALA H 8 1.362 1.285 1.126
+ 2ALA CA 9 1.233 1.289 1.298
+ 2ALA HA 10 1.269 1.295 1.401
+ 2ALA CB 11 1.107 1.379 1.286
+ 2ALA HB1 12 1.057 1.360 1.191
+ 2ALA HB2 13 1.034 1.369 1.366
+ 2ALA HB3 14 1.141 1.482 1.282
+ 2ALA C 15 1.192 1.141 1.266
+ 2ALA O 16 1.220 1.089 1.156
+ 3NME N 17 1.131 1.075 1.364
+ 3NME H 18 1.117 1.126 1.450
+ 3NME CH3 19 1.090 0.931 1.376
+ 3NME HH31 20 1.156 0.880 1.446
+ 3NME HH32 21 0.996 0.929 1.431
+ 3NME HH33 22 1.090 0.874 1.283
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 16.00000
+ 22
+ 1ACE HH31 1 1.587 1.386 1.166
+ 1ACE CH3 2 1.554 1.425 1.262
+ 1ACE HH32 3 1.559 1.534 1.266
+ 1ACE HH33 4 1.627 1.390 1.335
+ 1ACE C 5 1.417 1.372 1.300
+ 1ACE O 6 1.390 1.364 1.421
+ 2ALA N 7 1.334 1.344 1.205
+ 2ALA H 8 1.365 1.367 1.111
+ 2ALA CA 9 1.190 1.324 1.235
+ 2ALA HA 10 1.160 1.386 1.319
+ 2ALA CB 11 1.105 1.363 1.112
+ 2ALA HB1 12 1.129 1.297 1.029
+ 2ALA HB2 13 0.999 1.351 1.131
+ 2ALA HB3 14 1.125 1.467 1.088
+ 2ALA C 15 1.162 1.180 1.282
+ 2ALA O 16 1.054 1.128 1.258
+ 3NME N 17 1.261 1.106 1.318
+ 3NME H 18 1.349 1.152 1.336
+ 3NME CH3 19 1.250 0.960 1.324
+ 3NME HH31 20 1.264 0.908 1.229
+ 3NME HH32 21 1.322 0.926 1.399
+ 3NME HH33 22 1.153 0.923 1.357
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 17.00000
+ 22
+ 1ACE HH31 1 1.614 1.382 1.173
+ 1ACE CH3 2 1.559 1.432 1.253
+ 1ACE HH32 3 1.547 1.532 1.213
+ 1ACE HH33 4 1.625 1.444 1.339
+ 1ACE C 5 1.426 1.380 1.288
+ 1ACE O 6 1.411 1.348 1.406
+ 2ALA N 7 1.325 1.370 1.200
+ 2ALA H 8 1.341 1.388 1.102
+ 2ALA CA 9 1.189 1.318 1.239
+ 2ALA HA 10 1.170 1.358 1.338
+ 2ALA CB 11 1.084 1.388 1.158
+ 2ALA HB1 12 1.113 1.369 1.055
+ 2ALA HB2 13 0.994 1.336 1.189
+ 2ALA HB3 14 1.075 1.493 1.186
+ 2ALA C 15 1.170 1.163 1.252
+ 2ALA O 16 1.097 1.103 1.171
+ 3NME N 17 1.235 1.099 1.349
+ 3NME H 18 1.305 1.153 1.399
+ 3NME CH3 19 1.220 0.964 1.393
+ 3NME HH31 20 1.315 0.912 1.406
+ 3NME HH32 21 1.168 0.953 1.489
+ 3NME HH33 22 1.178 0.897 1.318
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 18.00000
+ 22
+ 1ACE HH31 1 1.555 1.419 1.126
+ 1ACE CH3 2 1.554 1.431 1.235
+ 1ACE HH32 3 1.554 1.535 1.267
+ 1ACE HH33 4 1.638 1.381 1.283
+ 1ACE C 5 1.423 1.378 1.292
+ 1ACE O 6 1.416 1.347 1.409
+ 2ALA N 7 1.322 1.351 1.211
+ 2ALA H 8 1.350 1.370 1.115
+ 2ALA CA 9 1.185 1.318 1.251
+ 2ALA HA 10 1.171 1.358 1.352
+ 2ALA CB 11 1.091 1.400 1.149
+ 2ALA HB1 12 1.059 1.346 1.060
+ 2ALA HB2 13 1.008 1.443 1.205
+ 2ALA HB3 14 1.154 1.480 1.109
+ 2ALA C 15 1.163 1.166 1.255
+ 2ALA O 16 1.060 1.108 1.214
+ 3NME N 17 1.255 1.102 1.328
+ 3NME H 18 1.335 1.159 1.354
+ 3NME CH3 19 1.246 0.964 1.369
+ 3NME HH31 20 1.154 0.913 1.344
+ 3NME HH32 21 1.323 0.899 1.327
+ 3NME HH33 22 1.251 0.953 1.477
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 19.00000
+ 22
+ 1ACE HH31 1 1.559 1.326 1.133
+ 1ACE CH3 2 1.552 1.413 1.200
+ 1ACE HH32 3 1.538 1.504 1.142
+ 1ACE HH33 4 1.631 1.428 1.273
+ 1ACE C 5 1.426 1.375 1.280
+ 1ACE O 6 1.428 1.345 1.398
+ 2ALA N 7 1.319 1.363 1.209
+ 2ALA H 8 1.322 1.382 1.110
+ 2ALA CA 9 1.191 1.329 1.265
+ 2ALA HA 10 1.186 1.364 1.368
+ 2ALA CB 11 1.075 1.391 1.178
+ 2ALA HB1 12 1.098 1.383 1.072
+ 2ALA HB2 13 0.980 1.348 1.211
+ 2ALA HB3 14 1.066 1.499 1.192
+ 2ALA C 15 1.169 1.174 1.275
+ 2ALA O 16 1.086 1.118 1.203
+ 3NME N 17 1.233 1.105 1.363
+ 3NME H 18 1.312 1.150 1.405
+ 3NME CH3 19 1.242 0.956 1.350
+ 3NME HH31 20 1.219 0.899 1.440
+ 3NME HH32 21 1.165 0.918 1.284
+ 3NME HH33 22 1.333 0.921 1.301
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 20.00000
+ 22
+ 1ACE HH31 1 1.622 1.459 1.287
+ 1ACE CH3 2 1.546 1.434 1.214
+ 1ACE HH32 3 1.578 1.365 1.135
+ 1ACE HH33 4 1.509 1.531 1.180
+ 1ACE C 5 1.430 1.358 1.283
+ 1ACE O 6 1.444 1.310 1.394
+ 2ALA N 7 1.315 1.370 1.215
+ 2ALA H 8 1.323 1.427 1.132
+ 2ALA CA 9 1.178 1.334 1.258
+ 2ALA HA 10 1.163 1.376 1.357
+ 2ALA CB 11 1.079 1.393 1.158
+ 2ALA HB1 12 1.096 1.348 1.060
+ 2ALA HB2 13 0.979 1.367 1.192
+ 2ALA HB3 14 1.087 1.501 1.165
+ 2ALA C 15 1.163 1.177 1.270
+ 2ALA O 16 1.073 1.114 1.216
+ 3NME N 17 1.249 1.110 1.347
+ 3NME H 18 1.324 1.165 1.388
+ 3NME CH3 19 1.242 0.964 1.360
+ 3NME HH31 20 1.325 0.920 1.416
+ 3NME HH32 21 1.151 0.938 1.414
+ 3NME HH33 22 1.221 0.913 1.266
+ 10.00000 10.00000 10.00000
diff --git a/regtest/basic/rt-ttmetad1/COLVAR.reference b/regtest/basic/rt-ttmetad1/COLVAR.reference
new file mode 100644
index 0000000000000000000000000000000000000000..583097c1733ddad1dd4b892214ae98e34f6d6962
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/COLVAR.reference
@@ -0,0 +1,24 @@
+#! FIELDS time phi psi metad1.bias metad2.bias metad3.bias metad4.bias metad5.bias metad6.bias metad1.transbias metad2.transbias metad3.transbias metad4.transbias metad5.transbias metad6.transbias
+#! SET min_phi -pi
+#! SET max_phi pi
+ 0.000000 -1.2379 1.9470 1.0000 1.0000 1.0000 1.0000 1.0000 1.0000 0.4000 0.6000 0.6000 0.6000 0.6000 0.4000
+ 1.000000 -1.4839 1.9381 1.0000 1.0000 0.8511 0.7916 1.0000 1.0000 0.4000 0.6000 0.6551 0.6000 0.6000 0.4000
+ 2.000000 -1.3243 1.9663 1.7837 1.7837 1.7676 1.7612 1.7837 1.7837 0.4000 0.6000 0.6768 0.6000 0.6000 0.4000
+ 3.000000 -1.3340 1.9885 2.9434 2.9434 2.9227 2.9146 2.9434 2.9434 0.4000 0.6000 0.7004 0.6000 0.6000 0.4000
+ 4.000000 -1.4613 1.8901 3.8047 3.8047 3.6802 3.6304 3.8047 3.8047 0.4000 0.6000 0.8277 0.6277 0.6000 0.4000
+ 5.000000 -1.2202 2.0306 3.8725 3.8725 3.8725 3.8725 3.8725 3.8725 0.4000 0.6000 0.8314 0.6314 0.6000 0.4000
+ 6.000000 -1.3883 1.8776 5.6213 5.6213 5.5645 5.5418 5.6213 5.6213 0.4000 0.6000 0.8863 0.6863 0.6000 0.4000
+ 7.000000 -1.5481 1.9488 5.5961 5.5961 5.3757 5.2888 5.5961 5.5961 0.4000 0.6000 1.0000 0.9624 0.6000 0.4000
+ 8.000000 -1.8429 1.9025 2.0232 2.0232 1.5305 1.3337 2.0232 2.0232 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
+ 9.000000 -2.2424 1.9813 1.2186 1.2186 1.0123 0.9279 1.2186 1.2186 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
+ 10.000000 -1.1482 1.9684 5.2099 5.2099 5.2099 5.2099 5.2099 5.2099 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
+ 11.000000 -1.7580 1.9807 4.1813 4.1813 3.7408 3.5658 4.1813 4.1813 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
+ 12.000000 -1.3186 1.9486 8.6178 8.6178 8.6047 8.5995 8.6178 8.6178 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
+ 13.000000 -2.9911 1.9547 0.9878 0.9878 0.9878 0.9878 0.9878 0.9878 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
+ 14.000000 -1.4112 2.0415 8.9808 8.9808 8.9106 8.8834 8.9808 8.9808 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
+ 15.000000 -2.5995 1.9166 1.4342 1.4342 1.4342 1.4342 1.4342 1.4342 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
+ 16.000000 -1.4608 1.9433 10.6386 10.6386 10.5186 10.4711 10.6386 10.6386 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
+ 17.000000 -1.3791 2.0625 10.4796 10.4796 10.4350 10.4179 10.4796 10.4796 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
+ 18.000000 -1.6771 1.9433 8.3031 8.3031 7.9412 7.7976 8.3031 8.3031 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
+ 19.000000 -1.5241 1.9642 12.2554 12.2554 12.0724 12.0004 12.2554 12.2554 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
+ 20.000000 -1.1997 1.9296 10.2734 10.2734 10.2734 10.2734 10.2734 10.2734 0.4000 0.6000 1.0000 1.0000 0.6000 0.4000
diff --git a/regtest/basic/rt-ttmetad1/HILLS-case1.reference b/regtest/basic/rt-ttmetad1/HILLS-case1.reference
new file mode 100644
index 0000000000000000000000000000000000000000..d532fbbf16a96a8909ac077c6bac1b34f0b6c86c
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/HILLS-case1.reference
@@ -0,0 +1,24 @@
+#! FIELDS time phi psi sigma_phi sigma_psi height biasf
+#! SET multivariate false
+#! SET min_phi -pi
+#! SET max_phi pi
+ 1 -1.483864797032211 1.938132764982607 0.2 0.2 1.2 -1
+ 2 -1.324349464027241 1.966349061093571 0.2 0.2 1.2 -1
+ 3 -1.334014372833683 1.988460591924974 0.2 0.2 1.2 -1
+ 4 -1.461334733547937 1.890108457957857 0.2 0.2 1.2 -1
+ 5 -1.220227832598179 2.030630313314516 0.2 0.2 1.2 -1
+ 6 -1.388275748836901 1.877631741588439 0.2 0.2 1.2 -1
+ 7 -1.548083770068421 1.9487542529822 0.2 0.2 1.2 -1
+ 8 -1.842857738569458 1.902457857730782 0.2 0.2 1.2 -1
+ 9 -2.242442614461024 1.981347055320541 0.2 0.2 1.2 -1
+ 10 -1.148221252978592 1.968444216110897 0.2 0.2 1.2 -1
+ 11 -1.757993684553651 1.980702405742474 0.2 0.2 1.2 -1
+ 12 -1.318567054245503 1.948618696187008 0.2 0.2 1.2 -1
+ 13 -2.991104158561357 1.954734059705066 0.2 0.2 1.2 -1
+ 14 -1.411190277910799 2.041520579428038 0.2 0.2 1.2 -1
+ 15 -2.59947290674873 1.916576972544074 0.2 0.2 1.2 -1
+ 16 -1.460820764733805 1.94328347326306 0.2 0.2 1.2 -1
+ 17 -1.379146894998496 2.062462992805603 0.2 0.2 1.2 -1
+ 18 -1.677124361971585 1.943260862166429 0.2 0.2 1.2 -1
+ 19 -1.524070841192655 1.964159206212332 0.2 0.2 1.2 -1
+ 20 -1.199652274777625 1.929638968944854 0.2 0.2 1.2 -1
diff --git a/regtest/basic/rt-ttmetad1/HILLS-case2.reference b/regtest/basic/rt-ttmetad1/HILLS-case2.reference
new file mode 100644
index 0000000000000000000000000000000000000000..d532fbbf16a96a8909ac077c6bac1b34f0b6c86c
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/HILLS-case2.reference
@@ -0,0 +1,24 @@
+#! FIELDS time phi psi sigma_phi sigma_psi height biasf
+#! SET multivariate false
+#! SET min_phi -pi
+#! SET max_phi pi
+ 1 -1.483864797032211 1.938132764982607 0.2 0.2 1.2 -1
+ 2 -1.324349464027241 1.966349061093571 0.2 0.2 1.2 -1
+ 3 -1.334014372833683 1.988460591924974 0.2 0.2 1.2 -1
+ 4 -1.461334733547937 1.890108457957857 0.2 0.2 1.2 -1
+ 5 -1.220227832598179 2.030630313314516 0.2 0.2 1.2 -1
+ 6 -1.388275748836901 1.877631741588439 0.2 0.2 1.2 -1
+ 7 -1.548083770068421 1.9487542529822 0.2 0.2 1.2 -1
+ 8 -1.842857738569458 1.902457857730782 0.2 0.2 1.2 -1
+ 9 -2.242442614461024 1.981347055320541 0.2 0.2 1.2 -1
+ 10 -1.148221252978592 1.968444216110897 0.2 0.2 1.2 -1
+ 11 -1.757993684553651 1.980702405742474 0.2 0.2 1.2 -1
+ 12 -1.318567054245503 1.948618696187008 0.2 0.2 1.2 -1
+ 13 -2.991104158561357 1.954734059705066 0.2 0.2 1.2 -1
+ 14 -1.411190277910799 2.041520579428038 0.2 0.2 1.2 -1
+ 15 -2.59947290674873 1.916576972544074 0.2 0.2 1.2 -1
+ 16 -1.460820764733805 1.94328347326306 0.2 0.2 1.2 -1
+ 17 -1.379146894998496 2.062462992805603 0.2 0.2 1.2 -1
+ 18 -1.677124361971585 1.943260862166429 0.2 0.2 1.2 -1
+ 19 -1.524070841192655 1.964159206212332 0.2 0.2 1.2 -1
+ 20 -1.199652274777625 1.929638968944854 0.2 0.2 1.2 -1
diff --git a/regtest/basic/rt-ttmetad1/HILLS-case3.reference b/regtest/basic/rt-ttmetad1/HILLS-case3.reference
new file mode 100644
index 0000000000000000000000000000000000000000..d532fbbf16a96a8909ac077c6bac1b34f0b6c86c
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/HILLS-case3.reference
@@ -0,0 +1,24 @@
+#! FIELDS time phi psi sigma_phi sigma_psi height biasf
+#! SET multivariate false
+#! SET min_phi -pi
+#! SET max_phi pi
+ 1 -1.483864797032211 1.938132764982607 0.2 0.2 1.2 -1
+ 2 -1.324349464027241 1.966349061093571 0.2 0.2 1.2 -1
+ 3 -1.334014372833683 1.988460591924974 0.2 0.2 1.2 -1
+ 4 -1.461334733547937 1.890108457957857 0.2 0.2 1.2 -1
+ 5 -1.220227832598179 2.030630313314516 0.2 0.2 1.2 -1
+ 6 -1.388275748836901 1.877631741588439 0.2 0.2 1.2 -1
+ 7 -1.548083770068421 1.9487542529822 0.2 0.2 1.2 -1
+ 8 -1.842857738569458 1.902457857730782 0.2 0.2 1.2 -1
+ 9 -2.242442614461024 1.981347055320541 0.2 0.2 1.2 -1
+ 10 -1.148221252978592 1.968444216110897 0.2 0.2 1.2 -1
+ 11 -1.757993684553651 1.980702405742474 0.2 0.2 1.2 -1
+ 12 -1.318567054245503 1.948618696187008 0.2 0.2 1.2 -1
+ 13 -2.991104158561357 1.954734059705066 0.2 0.2 1.2 -1
+ 14 -1.411190277910799 2.041520579428038 0.2 0.2 1.2 -1
+ 15 -2.59947290674873 1.916576972544074 0.2 0.2 1.2 -1
+ 16 -1.460820764733805 1.94328347326306 0.2 0.2 1.2 -1
+ 17 -1.379146894998496 2.062462992805603 0.2 0.2 1.2 -1
+ 18 -1.677124361971585 1.943260862166429 0.2 0.2 1.2 -1
+ 19 -1.524070841192655 1.964159206212332 0.2 0.2 1.2 -1
+ 20 -1.199652274777625 1.929638968944854 0.2 0.2 1.2 -1
diff --git a/regtest/basic/rt-ttmetad1/HILLS-case4.reference b/regtest/basic/rt-ttmetad1/HILLS-case4.reference
new file mode 100644
index 0000000000000000000000000000000000000000..d532fbbf16a96a8909ac077c6bac1b34f0b6c86c
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/HILLS-case4.reference
@@ -0,0 +1,24 @@
+#! FIELDS time phi psi sigma_phi sigma_psi height biasf
+#! SET multivariate false
+#! SET min_phi -pi
+#! SET max_phi pi
+ 1 -1.483864797032211 1.938132764982607 0.2 0.2 1.2 -1
+ 2 -1.324349464027241 1.966349061093571 0.2 0.2 1.2 -1
+ 3 -1.334014372833683 1.988460591924974 0.2 0.2 1.2 -1
+ 4 -1.461334733547937 1.890108457957857 0.2 0.2 1.2 -1
+ 5 -1.220227832598179 2.030630313314516 0.2 0.2 1.2 -1
+ 6 -1.388275748836901 1.877631741588439 0.2 0.2 1.2 -1
+ 7 -1.548083770068421 1.9487542529822 0.2 0.2 1.2 -1
+ 8 -1.842857738569458 1.902457857730782 0.2 0.2 1.2 -1
+ 9 -2.242442614461024 1.981347055320541 0.2 0.2 1.2 -1
+ 10 -1.148221252978592 1.968444216110897 0.2 0.2 1.2 -1
+ 11 -1.757993684553651 1.980702405742474 0.2 0.2 1.2 -1
+ 12 -1.318567054245503 1.948618696187008 0.2 0.2 1.2 -1
+ 13 -2.991104158561357 1.954734059705066 0.2 0.2 1.2 -1
+ 14 -1.411190277910799 2.041520579428038 0.2 0.2 1.2 -1
+ 15 -2.59947290674873 1.916576972544074 0.2 0.2 1.2 -1
+ 16 -1.460820764733805 1.94328347326306 0.2 0.2 1.2 -1
+ 17 -1.379146894998496 2.062462992805603 0.2 0.2 1.2 -1
+ 18 -1.677124361971585 1.943260862166429 0.2 0.2 1.2 -1
+ 19 -1.524070841192655 1.964159206212332 0.2 0.2 1.2 -1
+ 20 -1.199652274777625 1.929638968944854 0.2 0.2 1.2 -1
diff --git a/regtest/basic/rt-ttmetad1/HILLS-case5.reference b/regtest/basic/rt-ttmetad1/HILLS-case5.reference
new file mode 100644
index 0000000000000000000000000000000000000000..d532fbbf16a96a8909ac077c6bac1b34f0b6c86c
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/HILLS-case5.reference
@@ -0,0 +1,24 @@
+#! FIELDS time phi psi sigma_phi sigma_psi height biasf
+#! SET multivariate false
+#! SET min_phi -pi
+#! SET max_phi pi
+ 1 -1.483864797032211 1.938132764982607 0.2 0.2 1.2 -1
+ 2 -1.324349464027241 1.966349061093571 0.2 0.2 1.2 -1
+ 3 -1.334014372833683 1.988460591924974 0.2 0.2 1.2 -1
+ 4 -1.461334733547937 1.890108457957857 0.2 0.2 1.2 -1
+ 5 -1.220227832598179 2.030630313314516 0.2 0.2 1.2 -1
+ 6 -1.388275748836901 1.877631741588439 0.2 0.2 1.2 -1
+ 7 -1.548083770068421 1.9487542529822 0.2 0.2 1.2 -1
+ 8 -1.842857738569458 1.902457857730782 0.2 0.2 1.2 -1
+ 9 -2.242442614461024 1.981347055320541 0.2 0.2 1.2 -1
+ 10 -1.148221252978592 1.968444216110897 0.2 0.2 1.2 -1
+ 11 -1.757993684553651 1.980702405742474 0.2 0.2 1.2 -1
+ 12 -1.318567054245503 1.948618696187008 0.2 0.2 1.2 -1
+ 13 -2.991104158561357 1.954734059705066 0.2 0.2 1.2 -1
+ 14 -1.411190277910799 2.041520579428038 0.2 0.2 1.2 -1
+ 15 -2.59947290674873 1.916576972544074 0.2 0.2 1.2 -1
+ 16 -1.460820764733805 1.94328347326306 0.2 0.2 1.2 -1
+ 17 -1.379146894998496 2.062462992805603 0.2 0.2 1.2 -1
+ 18 -1.677124361971585 1.943260862166429 0.2 0.2 1.2 -1
+ 19 -1.524070841192655 1.964159206212332 0.2 0.2 1.2 -1
+ 20 -1.199652274777625 1.929638968944854 0.2 0.2 1.2 -1
diff --git a/regtest/basic/rt-ttmetad1/HILLS-case6.reference b/regtest/basic/rt-ttmetad1/HILLS-case6.reference
new file mode 100644
index 0000000000000000000000000000000000000000..d532fbbf16a96a8909ac077c6bac1b34f0b6c86c
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/HILLS-case6.reference
@@ -0,0 +1,24 @@
+#! FIELDS time phi psi sigma_phi sigma_psi height biasf
+#! SET multivariate false
+#! SET min_phi -pi
+#! SET max_phi pi
+ 1 -1.483864797032211 1.938132764982607 0.2 0.2 1.2 -1
+ 2 -1.324349464027241 1.966349061093571 0.2 0.2 1.2 -1
+ 3 -1.334014372833683 1.988460591924974 0.2 0.2 1.2 -1
+ 4 -1.461334733547937 1.890108457957857 0.2 0.2 1.2 -1
+ 5 -1.220227832598179 2.030630313314516 0.2 0.2 1.2 -1
+ 6 -1.388275748836901 1.877631741588439 0.2 0.2 1.2 -1
+ 7 -1.548083770068421 1.9487542529822 0.2 0.2 1.2 -1
+ 8 -1.842857738569458 1.902457857730782 0.2 0.2 1.2 -1
+ 9 -2.242442614461024 1.981347055320541 0.2 0.2 1.2 -1
+ 10 -1.148221252978592 1.968444216110897 0.2 0.2 1.2 -1
+ 11 -1.757993684553651 1.980702405742474 0.2 0.2 1.2 -1
+ 12 -1.318567054245503 1.948618696187008 0.2 0.2 1.2 -1
+ 13 -2.991104158561357 1.954734059705066 0.2 0.2 1.2 -1
+ 14 -1.411190277910799 2.041520579428038 0.2 0.2 1.2 -1
+ 15 -2.59947290674873 1.916576972544074 0.2 0.2 1.2 -1
+ 16 -1.460820764733805 1.94328347326306 0.2 0.2 1.2 -1
+ 17 -1.379146894998496 2.062462992805603 0.2 0.2 1.2 -1
+ 18 -1.677124361971585 1.943260862166429 0.2 0.2 1.2 -1
+ 19 -1.524070841192655 1.964159206212332 0.2 0.2 1.2 -1
+ 20 -1.199652274777625 1.929638968944854 0.2 0.2 1.2 -1
diff --git a/regtest/basic/rt-ttmetad1/Makefile b/regtest/basic/rt-ttmetad1/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..3703b27cea227aa053fb6d1d73f861e4384dbcee
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/Makefile
@@ -0,0 +1 @@
+include ../../scripts/test.make
diff --git a/regtest/basic/rt-ttmetad1/config b/regtest/basic/rt-ttmetad1/config
new file mode 100644
index 0000000000000000000000000000000000000000..ce858d0c5a1fc8ff0fa3f73d5836edaf432c82e8
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/config
@@ -0,0 +1,3 @@
+type=driver
+# this is to test a different name
+arg="--plumed plumed.dat --trajectory-stride 500 --timestep 0.002 --igro traj.gro"
diff --git a/regtest/basic/rt-ttmetad1/grid-case1 b/regtest/basic/rt-ttmetad1/grid-case1
new file mode 100644
index 0000000000000000000000000000000000000000..a68b1d976d4b66cc7e870104a63e2fef1e694aca
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/grid-case1
@@ -0,0 +1,129 @@
+ #! FIELDS phi psi metad1.bias der_phi der_psi
+ #! SET min_phi -pi
+ #! SET max_phi pi
+ #! SET nbins_phi 10
+ #! SET periodic_phi true
+ #! SET min_psi 0
+ #! SET max_psi pi
+ #! SET nbins_psi 11
+ #! SET periodic_psi false
+ -3.14159274 0.00000000 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.00000000 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.00000000 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.00000000 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.00000000 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.00000000 0.600000000 0.00000000 0.00000000
+ 0.628318548 0.00000000 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.00000000 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.00000000 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.00000000 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.314159274 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.314159274 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.314159274 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.314159274 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.314159274 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.314159274 0.500000000 0.00000000 0.00000000
+ 0.628318548 0.314159274 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.314159274 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.314159274 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.314159274 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.628318548 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.628318548 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.628318548 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.628318548 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.628318548 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.628318548 0.500000000 0.00000000 0.00000000
+ 0.628318548 0.628318548 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.628318548 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.628318548 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.628318548 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.942477822 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.942477822 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.942477822 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.942477822 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.942477822 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.942477822 0.500000000 0.00000000 0.00000000
+ 0.628318548 0.942477822 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.942477822 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.942477822 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.942477822 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 1.25663710 0.300000012 0.00000000 0.00000000
+ -2.51327419 1.25663710 0.300000012 0.00000000 0.00000000
+ -1.88495564 1.25663710 0.300000012 0.00000000 0.00000000
+ -1.25663710 1.25663710 0.300000012 0.00000000 0.00000000
+ -0.628318548 1.25663710 0.300000012 0.00000000 0.00000000
+ 0.00000000 1.25663710 0.400000012 0.00000000 0.00000000
+ 0.628318548 1.25663710 0.300000012 0.00000000 0.00000000
+ 1.25663686 1.25663710 0.300000012 0.00000000 0.00000000
+ 1.88495564 1.25663710 0.300000012 0.00000000 0.00000000
+ 2.51327443 1.25663710 0.300000012 0.00000000 0.00000000
+
+ -3.14159274 1.57079637 1.00000000 0.00000000 0.00000000
+ -2.51327419 1.57079637 1.00000000 0.00000000 0.00000000
+ -1.88495564 1.57079637 1.00000000 0.00000000 0.00000000
+ -1.25663710 1.57079637 1.00000000 0.00000000 0.00000000
+ -0.628318548 1.57079637 1.00000000 0.00000000 0.00000000
+ 0.00000000 1.57079637 0.500000000 0.00000000 0.00000000
+ 0.628318548 1.57079637 1.00000000 0.00000000 0.00000000
+ 1.25663686 1.57079637 1.00000000 0.00000000 0.00000000
+ 1.88495564 1.57079637 1.00000000 0.00000000 0.00000000
+ 2.51327443 1.57079637 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 1.88495564 1.00000000 0.00000000 0.00000000
+ -2.51327419 1.88495564 1.00000000 0.00000000 0.00000000
+ -1.88495564 1.88495564 1.00000000 0.00000000 0.00000000
+ -1.25663710 1.88495564 1.00000000 0.00000000 0.00000000
+ -0.628318548 1.88495564 1.00000000 0.00000000 0.00000000
+ 0.00000000 1.88495564 0.500000000 0.00000000 0.00000000
+ 0.628318548 1.88495564 1.00000000 0.00000000 0.00000000
+ 1.25663686 1.88495564 1.00000000 0.00000000 0.00000000
+ 1.88495564 1.88495564 1.00000000 0.00000000 0.00000000
+ 2.51327443 1.88495564 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 2.19911480 1.00000000 0.00000000 0.00000000
+ -2.51327419 2.19911480 1.00000000 0.00000000 0.00000000
+ -1.88495564 2.19911480 1.00000000 0.00000000 0.00000000
+ -1.25663710 2.19911480 1.00000000 0.00000000 0.00000000
+ -0.628318548 2.19911480 1.00000000 0.00000000 0.00000000
+ 0.00000000 2.19911480 0.500000000 0.00000000 0.00000000
+ 0.628318548 2.19911480 1.00000000 0.00000000 0.00000000
+ 1.25663686 2.19911480 1.00000000 0.00000000 0.00000000
+ 1.88495564 2.19911480 1.00000000 0.00000000 0.00000000
+ 2.51327443 2.19911480 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 2.51327419 1.00000000 0.00000000 0.00000000
+ -2.51327419 2.51327419 1.00000000 0.00000000 0.00000000
+ -1.88495564 2.51327419 1.00000000 0.00000000 0.00000000
+ -1.25663710 2.51327419 1.00000000 0.00000000 0.00000000
+ -0.628318548 2.51327419 1.00000000 0.00000000 0.00000000
+ 0.00000000 2.51327419 0.500000000 0.00000000 0.00000000
+ 0.628318548 2.51327419 1.00000000 0.00000000 0.00000000
+ 1.25663686 2.51327419 1.00000000 0.00000000 0.00000000
+ 1.88495564 2.51327419 1.00000000 0.00000000 0.00000000
+ 2.51327443 2.51327419 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 2.82743359 1.00000000 0.00000000 0.00000000
+ -2.51327419 2.82743359 1.00000000 0.00000000 0.00000000
+ -1.88495564 2.82743359 1.00000000 0.00000000 0.00000000
+ -1.25663710 2.82743359 1.00000000 0.00000000 0.00000000
+ -0.628318548 2.82743359 1.00000000 0.00000000 0.00000000
+ 0.00000000 2.82743359 0.500000000 0.00000000 0.00000000
+ 0.628318548 2.82743359 1.00000000 0.00000000 0.00000000
+ 1.25663686 2.82743359 1.00000000 0.00000000 0.00000000
+ 1.88495564 2.82743359 1.00000000 0.00000000 0.00000000
+ 2.51327443 2.82743359 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 3.14159274 1.00000000 0.00000000 0.00000000
+ -2.51327419 3.14159274 1.00000000 0.00000000 0.00000000
+ -1.88495564 3.14159274 1.00000000 0.00000000 0.00000000
+ -1.25663710 3.14159274 1.00000000 0.00000000 0.00000000
+ -0.628318548 3.14159274 1.00000000 0.00000000 0.00000000
+ 0.00000000 3.14159274 0.500000000 0.00000000 0.00000000
+ 0.628318548 3.14159274 1.00000000 0.00000000 0.00000000
+ 1.25663686 3.14159274 1.00000000 0.00000000 0.00000000
+ 1.88495564 3.14159274 1.00000000 0.00000000 0.00000000
+ 2.51327443 3.14159274 1.00000000 0.00000000 0.00000000
diff --git a/regtest/basic/rt-ttmetad1/grid-case2 b/regtest/basic/rt-ttmetad1/grid-case2
new file mode 100644
index 0000000000000000000000000000000000000000..25d3147c62792600235a6d71e4d533799e3f1ba5
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/grid-case2
@@ -0,0 +1,129 @@
+ #! FIELDS phi psi metad2.bias der_phi der_psi
+ #! SET min_phi -pi
+ #! SET max_phi pi
+ #! SET nbins_phi 10
+ #! SET periodic_phi true
+ #! SET min_psi 0
+ #! SET max_psi pi
+ #! SET nbins_psi 11
+ #! SET periodic_psi false
+ -3.14159274 0.00000000 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.00000000 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.00000000 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.00000000 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.00000000 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.00000000 0.300000012 0.00000000 0.00000000
+ 0.628318548 0.00000000 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.00000000 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.00000000 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.00000000 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.314159274 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.314159274 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.314159274 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.314159274 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.314159274 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.314159274 0.300000012 0.00000000 0.00000000
+ 0.628318548 0.314159274 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.314159274 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.314159274 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.314159274 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.628318548 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.628318548 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.628318548 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.628318548 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.628318548 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.628318548 0.300000012 0.00000000 0.00000000
+ 0.628318548 0.628318548 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.628318548 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.628318548 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.628318548 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.942477822 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.942477822 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.942477822 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.942477822 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.942477822 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.942477822 0.300000012 0.00000000 0.00000000
+ 0.628318548 0.942477822 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.942477822 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.942477822 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.942477822 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 1.25663710 0.500000000 0.00000000 0.00000000
+ -2.51327419 1.25663710 0.500000000 0.00000000 0.00000000
+ -1.88495564 1.25663710 0.500000000 0.00000000 0.00000000
+ -1.25663710 1.25663710 0.500000000 0.00000000 0.00000000
+ -0.628318548 1.25663710 0.500000000 0.00000000 0.00000000
+ 0.00000000 1.25663710 0.500000000 0.00000000 0.00000000
+ 0.628318548 1.25663710 0.600000000 0.00000000 0.00000000
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+ 1.88495564 1.25663710 0.500000000 0.00000000 0.00000000
+ 2.51327443 1.25663710 0.500000000 0.00000000 0.00000000
+
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+ -1.88495564 1.57079637 1.00000000 0.00000000 0.00000000
+ -1.25663710 1.57079637 1.00000000 0.00000000 0.00000000
+ -0.628318548 1.57079637 1.00000000 0.00000000 0.00000000
+ 0.00000000 1.57079637 0.300000012 0.00000000 0.00000000
+ 0.628318548 1.57079637 1.00000000 0.00000000 0.00000000
+ 1.25663686 1.57079637 1.00000000 0.00000000 0.00000000
+ 1.88495564 1.57079637 1.00000000 0.00000000 0.00000000
+ 2.51327443 1.57079637 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 1.88495564 1.00000000 0.00000000 0.00000000
+ -2.51327419 1.88495564 1.00000000 0.00000000 0.00000000
+ -1.88495564 1.88495564 1.00000000 0.00000000 0.00000000
+ -1.25663710 1.88495564 1.00000000 0.00000000 0.00000000
+ -0.628318548 1.88495564 1.00000000 0.00000000 0.00000000
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+
+ -3.14159274 2.19911480 1.00000000 0.00000000 0.00000000
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+ -1.88495564 2.19911480 1.00000000 0.00000000 0.00000000
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+ -0.628318548 2.19911480 1.00000000 0.00000000 0.00000000
+ 0.00000000 2.19911480 0.300000012 0.00000000 0.00000000
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+ 2.51327443 2.19911480 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 2.51327419 1.00000000 0.00000000 0.00000000
+ -2.51327419 2.51327419 1.00000000 0.00000000 0.00000000
+ -1.88495564 2.51327419 1.00000000 0.00000000 0.00000000
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+ -0.628318548 2.51327419 1.00000000 0.00000000 0.00000000
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+ 2.51327443 2.51327419 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 2.82743359 1.00000000 0.00000000 0.00000000
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+ -1.88495564 2.82743359 1.00000000 0.00000000 0.00000000
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+ -0.628318548 2.82743359 1.00000000 0.00000000 0.00000000
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+ 0.628318548 2.82743359 1.00000000 0.00000000 0.00000000
+ 1.25663686 2.82743359 1.00000000 0.00000000 0.00000000
+ 1.88495564 2.82743359 1.00000000 0.00000000 0.00000000
+ 2.51327443 2.82743359 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 3.14159274 1.00000000 0.00000000 0.00000000
+ -2.51327419 3.14159274 1.00000000 0.00000000 0.00000000
+ -1.88495564 3.14159274 1.00000000 0.00000000 0.00000000
+ -1.25663710 3.14159274 1.00000000 0.00000000 0.00000000
+ -0.628318548 3.14159274 1.00000000 0.00000000 0.00000000
+ 0.00000000 3.14159274 0.300000012 0.00000000 0.00000000
+ 0.628318548 3.14159274 1.00000000 0.00000000 0.00000000
+ 1.25663686 3.14159274 1.00000000 0.00000000 0.00000000
+ 1.88495564 3.14159274 1.00000000 0.00000000 0.00000000
+ 2.51327443 3.14159274 1.00000000 0.00000000 0.00000000
diff --git a/regtest/basic/rt-ttmetad1/grid-case3 b/regtest/basic/rt-ttmetad1/grid-case3
new file mode 100644
index 0000000000000000000000000000000000000000..ede1553341460eba054283a062efd0dc39d8f369
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/grid-case3
@@ -0,0 +1,129 @@
+ #! FIELDS phi psi metad3.bias der_phi der_psi
+ #! SET min_phi -pi
+ #! SET max_phi pi
+ #! SET nbins_phi 10
+ #! SET periodic_phi true
+ #! SET min_psi 0
+ #! SET max_psi pi
+ #! SET nbins_psi 11
+ #! SET periodic_psi false
+ -3.14159274 0.00000000 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.00000000 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.00000000 0.600000000 0.00000000 0.00000000
+ -1.25663710 0.00000000 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.00000000 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.00000000 0.300000012 0.00000000 0.00000000
+ 0.628318548 0.00000000 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.00000000 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.00000000 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.00000000 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.314159274 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.314159274 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.314159274 0.500000000 0.00000000 0.00000000
+ -1.25663710 0.314159274 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.314159274 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.314159274 0.300000012 0.00000000 0.00000000
+ 0.628318548 0.314159274 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.314159274 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.314159274 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.314159274 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.628318548 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.628318548 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.628318548 0.500000000 0.00000000 0.00000000
+ -1.25663710 0.628318548 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.628318548 1.00000000 0.00000000 0.00000000
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+
+ -3.14159274 0.942477822 1.00000000 0.00000000 0.00000000
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+ -1.88495564 0.942477822 0.500000000 0.00000000 0.00000000
+ -1.25663710 0.942477822 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.942477822 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.942477822 0.300000012 0.00000000 0.00000000
+ 0.628318548 0.942477822 1.00000000 0.00000000 0.00000000
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+ 1.88495564 0.942477822 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.942477822 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 1.25663710 1.00000000 0.00000000 0.00000000
+ -2.51327419 1.25663710 1.00000000 0.00000000 0.00000000
+ -1.88495564 1.25663710 0.500000000 0.00000000 0.00000000
+ -1.25663710 1.25663710 1.00000000 0.00000000 0.00000000
+ -0.628318548 1.25663710 1.00000000 0.00000000 0.00000000
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+
+ -3.14159274 1.57079637 1.00000000 0.00000000 0.00000000
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+ -1.88495564 1.57079637 0.500000000 0.00000000 0.00000000
+ -1.25663710 1.57079637 1.00000000 0.00000000 0.00000000
+ -0.628318548 1.57079637 1.00000000 0.00000000 0.00000000
+ 0.00000000 1.57079637 0.300000012 0.00000000 0.00000000
+ 0.628318548 1.57079637 1.00000000 0.00000000 0.00000000
+ 1.25663686 1.57079637 1.00000000 0.00000000 0.00000000
+ 1.88495564 1.57079637 1.00000000 0.00000000 0.00000000
+ 2.51327443 1.57079637 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 1.88495564 1.00000000 0.00000000 0.00000000
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+ -1.88495564 1.88495564 0.500000000 0.00000000 0.00000000
+ -1.25663710 1.88495564 1.00000000 0.00000000 0.00000000
+ -0.628318548 1.88495564 1.00000000 0.00000000 0.00000000
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+
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+ -1.88495564 2.19911480 0.500000000 0.00000000 0.00000000
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+ -0.628318548 2.19911480 1.00000000 0.00000000 0.00000000
+ 0.00000000 2.19911480 0.300000012 0.00000000 0.00000000
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+ 2.51327443 2.19911480 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 2.51327419 1.00000000 0.00000000 0.00000000
+ -2.51327419 2.51327419 1.00000000 0.00000000 0.00000000
+ -1.88495564 2.51327419 0.500000000 0.00000000 0.00000000
+ -1.25663710 2.51327419 1.00000000 0.00000000 0.00000000
+ -0.628318548 2.51327419 1.00000000 0.00000000 0.00000000
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+
+ -3.14159274 2.82743359 1.00000000 0.00000000 0.00000000
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+ -1.88495564 2.82743359 0.500000000 0.00000000 0.00000000
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+ 1.88495564 2.82743359 1.00000000 0.00000000 0.00000000
+ 2.51327443 2.82743359 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 3.14159274 1.00000000 0.00000000 0.00000000
+ -2.51327419 3.14159274 1.00000000 0.00000000 0.00000000
+ -1.88495564 3.14159274 0.500000000 0.00000000 0.00000000
+ -1.25663710 3.14159274 1.00000000 0.00000000 0.00000000
+ -0.628318548 3.14159274 1.00000000 0.00000000 0.00000000
+ 0.00000000 3.14159274 0.300000012 0.00000000 0.00000000
+ 0.628318548 3.14159274 1.00000000 0.00000000 0.00000000
+ 1.25663686 3.14159274 1.00000000 0.00000000 0.00000000
+ 1.88495564 3.14159274 1.00000000 0.00000000 0.00000000
+ 2.51327443 3.14159274 1.00000000 0.00000000 0.00000000
diff --git a/regtest/basic/rt-ttmetad1/grid-case4 b/regtest/basic/rt-ttmetad1/grid-case4
new file mode 100644
index 0000000000000000000000000000000000000000..1bb216553bee2110f2413b2731e0dfba9d657318
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/grid-case4
@@ -0,0 +1,129 @@
+ #! FIELDS phi psi metad4.bias der_phi der_psi
+ #! SET min_phi -pi
+ #! SET max_phi pi
+ #! SET nbins_phi 10
+ #! SET periodic_phi true
+ #! SET min_psi 0
+ #! SET max_psi pi
+ #! SET nbins_psi 11
+ #! SET periodic_psi false
+ -3.14159274 0.00000000 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.00000000 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.00000000 0.300000012 0.00000000 0.00000000
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+ 1.88495564 0.00000000 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.00000000 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.314159274 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.314159274 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.314159274 0.300000012 0.00000000 0.00000000
+ -1.25663710 0.314159274 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.314159274 1.00000000 0.00000000 0.00000000
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+ 2.51327443 0.314159274 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.628318548 1.00000000 0.00000000 0.00000000
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+
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+
+ -3.14159274 2.82743359 1.00000000 0.00000000 0.00000000
+ -2.51327419 2.82743359 1.00000000 0.00000000 0.00000000
+ -1.88495564 2.82743359 0.300000012 0.00000000 0.00000000
+ -1.25663710 2.82743359 1.00000000 0.00000000 0.00000000
+ -0.628318548 2.82743359 1.00000000 0.00000000 0.00000000
+ 0.00000000 2.82743359 0.500000000 0.00000000 0.00000000
+ 0.628318548 2.82743359 1.00000000 0.00000000 0.00000000
+ 1.25663686 2.82743359 1.00000000 0.00000000 0.00000000
+ 1.88495564 2.82743359 1.00000000 0.00000000 0.00000000
+ 2.51327443 2.82743359 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 3.14159274 1.00000000 0.00000000 0.00000000
+ -2.51327419 3.14159274 1.00000000 0.00000000 0.00000000
+ -1.88495564 3.14159274 0.300000012 0.00000000 0.00000000
+ -1.25663710 3.14159274 1.00000000 0.00000000 0.00000000
+ -0.628318548 3.14159274 1.00000000 0.00000000 0.00000000
+ 0.00000000 3.14159274 0.500000000 0.00000000 0.00000000
+ 0.628318548 3.14159274 1.00000000 0.00000000 0.00000000
+ 1.25663686 3.14159274 1.00000000 0.00000000 0.00000000
+ 1.88495564 3.14159274 1.00000000 0.00000000 0.00000000
+ 2.51327443 3.14159274 1.00000000 0.00000000 0.00000000
diff --git a/regtest/basic/rt-ttmetad1/grid-case5 b/regtest/basic/rt-ttmetad1/grid-case5
new file mode 100644
index 0000000000000000000000000000000000000000..152353a78fc26bd2b1775846bfb7c803a7bb1c65
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/grid-case5
@@ -0,0 +1,129 @@
+ #! FIELDS phi psi metad5.bias der_phi der_psi
+ #! SET min_phi -pi
+ #! SET max_phi pi
+ #! SET nbins_phi 10
+ #! SET periodic_phi true
+ #! SET min_psi 0
+ #! SET max_psi pi
+ #! SET nbins_psi 11
+ #! SET periodic_psi false
+ -3.14159274 0.00000000 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.00000000 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.00000000 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.00000000 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.00000000 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.00000000 1.00000000 0.00000000 0.00000000
+ 0.628318548 0.00000000 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.00000000 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.00000000 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.00000000 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.314159274 0.300000012 0.00000000 0.00000000
+ -2.51327419 0.314159274 0.300000012 0.00000000 0.00000000
+ -1.88495564 0.314159274 0.400000012 0.00000000 0.00000000
+ -1.25663710 0.314159274 0.300000012 0.00000000 0.00000000
+ -0.628318548 0.314159274 0.300000012 0.00000000 0.00000000
+ 0.00000000 0.314159274 0.300000012 0.00000000 0.00000000
+ 0.628318548 0.314159274 0.300000012 0.00000000 0.00000000
+ 1.25663686 0.314159274 0.300000012 0.00000000 0.00000000
+ 1.88495564 0.314159274 0.300000012 0.00000000 0.00000000
+ 2.51327443 0.314159274 0.300000012 0.00000000 0.00000000
+
+ -3.14159274 0.628318548 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.628318548 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.628318548 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.628318548 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.628318548 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.628318548 1.00000000 0.00000000 0.00000000
+ 0.628318548 0.628318548 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.628318548 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.628318548 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.628318548 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.942477822 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.942477822 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.942477822 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.942477822 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.942477822 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.942477822 1.00000000 0.00000000 0.00000000
+ 0.628318548 0.942477822 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.942477822 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.942477822 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.942477822 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 1.25663710 0.500000000 0.00000000 0.00000000
+ -2.51327419 1.25663710 0.500000000 0.00000000 0.00000000
+ -1.88495564 1.25663710 0.500000000 0.00000000 0.00000000
+ -1.25663710 1.25663710 0.500000000 0.00000000 0.00000000
+ -0.628318548 1.25663710 0.500000000 0.00000000 0.00000000
+ 0.00000000 1.25663710 0.500000000 0.00000000 0.00000000
+ 0.628318548 1.25663710 0.500000000 0.00000000 0.00000000
+ 1.25663686 1.25663710 0.600000000 0.00000000 0.00000000
+ 1.88495564 1.25663710 0.500000000 0.00000000 0.00000000
+ 2.51327443 1.25663710 0.500000000 0.00000000 0.00000000
+
+ -3.14159274 1.57079637 1.00000000 0.00000000 0.00000000
+ -2.51327419 1.57079637 1.00000000 0.00000000 0.00000000
+ -1.88495564 1.57079637 1.00000000 0.00000000 0.00000000
+ -1.25663710 1.57079637 1.00000000 0.00000000 0.00000000
+ -0.628318548 1.57079637 1.00000000 0.00000000 0.00000000
+ 0.00000000 1.57079637 1.00000000 0.00000000 0.00000000
+ 0.628318548 1.57079637 1.00000000 0.00000000 0.00000000
+ 1.25663686 1.57079637 1.00000000 0.00000000 0.00000000
+ 1.88495564 1.57079637 1.00000000 0.00000000 0.00000000
+ 2.51327443 1.57079637 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 1.88495564 1.00000000 0.00000000 0.00000000
+ -2.51327419 1.88495564 1.00000000 0.00000000 0.00000000
+ -1.88495564 1.88495564 1.00000000 0.00000000 0.00000000
+ -1.25663710 1.88495564 1.00000000 0.00000000 0.00000000
+ -0.628318548 1.88495564 1.00000000 0.00000000 0.00000000
+ 0.00000000 1.88495564 1.00000000 0.00000000 0.00000000
+ 0.628318548 1.88495564 1.00000000 0.00000000 0.00000000
+ 1.25663686 1.88495564 1.00000000 0.00000000 0.00000000
+ 1.88495564 1.88495564 1.00000000 0.00000000 0.00000000
+ 2.51327443 1.88495564 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 2.19911480 1.00000000 0.00000000 0.00000000
+ -2.51327419 2.19911480 1.00000000 0.00000000 0.00000000
+ -1.88495564 2.19911480 1.00000000 0.00000000 0.00000000
+ -1.25663710 2.19911480 1.00000000 0.00000000 0.00000000
+ -0.628318548 2.19911480 1.00000000 0.00000000 0.00000000
+ 0.00000000 2.19911480 1.00000000 0.00000000 0.00000000
+ 0.628318548 2.19911480 1.00000000 0.00000000 0.00000000
+ 1.25663686 2.19911480 1.00000000 0.00000000 0.00000000
+ 1.88495564 2.19911480 1.00000000 0.00000000 0.00000000
+ 2.51327443 2.19911480 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 2.51327419 1.00000000 0.00000000 0.00000000
+ -2.51327419 2.51327419 1.00000000 0.00000000 0.00000000
+ -1.88495564 2.51327419 1.00000000 0.00000000 0.00000000
+ -1.25663710 2.51327419 1.00000000 0.00000000 0.00000000
+ -0.628318548 2.51327419 1.00000000 0.00000000 0.00000000
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+ 0.628318548 2.51327419 1.00000000 0.00000000 0.00000000
+ 1.25663686 2.51327419 1.00000000 0.00000000 0.00000000
+ 1.88495564 2.51327419 1.00000000 0.00000000 0.00000000
+ 2.51327443 2.51327419 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 2.82743359 1.00000000 0.00000000 0.00000000
+ -2.51327419 2.82743359 1.00000000 0.00000000 0.00000000
+ -1.88495564 2.82743359 1.00000000 0.00000000 0.00000000
+ -1.25663710 2.82743359 1.00000000 0.00000000 0.00000000
+ -0.628318548 2.82743359 1.00000000 0.00000000 0.00000000
+ 0.00000000 2.82743359 1.00000000 0.00000000 0.00000000
+ 0.628318548 2.82743359 1.00000000 0.00000000 0.00000000
+ 1.25663686 2.82743359 1.00000000 0.00000000 0.00000000
+ 1.88495564 2.82743359 1.00000000 0.00000000 0.00000000
+ 2.51327443 2.82743359 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 3.14159274 1.00000000 0.00000000 0.00000000
+ -2.51327419 3.14159274 1.00000000 0.00000000 0.00000000
+ -1.88495564 3.14159274 1.00000000 0.00000000 0.00000000
+ -1.25663710 3.14159274 1.00000000 0.00000000 0.00000000
+ -0.628318548 3.14159274 1.00000000 0.00000000 0.00000000
+ 0.00000000 3.14159274 1.00000000 0.00000000 0.00000000
+ 0.628318548 3.14159274 1.00000000 0.00000000 0.00000000
+ 1.25663686 3.14159274 1.00000000 0.00000000 0.00000000
+ 1.88495564 3.14159274 1.00000000 0.00000000 0.00000000
+ 2.51327443 3.14159274 1.00000000 0.00000000 0.00000000
diff --git a/regtest/basic/rt-ttmetad1/grid-case6 b/regtest/basic/rt-ttmetad1/grid-case6
new file mode 100644
index 0000000000000000000000000000000000000000..50267706363a8418507f4565700503a668129d7a
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/grid-case6
@@ -0,0 +1,129 @@
+ #! FIELDS phi psi metad6.bias der_phi der_psi
+ #! SET min_phi -pi
+ #! SET max_phi pi
+ #! SET nbins_phi 10
+ #! SET periodic_phi true
+ #! SET min_psi 0
+ #! SET max_psi pi
+ #! SET nbins_psi 11
+ #! SET periodic_psi false
+ -3.14159274 0.00000000 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.00000000 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.00000000 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.00000000 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.00000000 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.00000000 1.00000000 0.00000000 0.00000000
+ 0.628318548 0.00000000 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.00000000 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.00000000 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.00000000 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.314159274 0.500000000 0.00000000 0.00000000
+ -2.51327419 0.314159274 0.500000000 0.00000000 0.00000000
+ -1.88495564 0.314159274 0.500000000 0.00000000 0.00000000
+ -1.25663710 0.314159274 0.500000000 0.00000000 0.00000000
+ -0.628318548 0.314159274 0.500000000 0.00000000 0.00000000
+ 0.00000000 0.314159274 0.500000000 0.00000000 0.00000000
+ 0.628318548 0.314159274 0.500000000 0.00000000 0.00000000
+ 1.25663686 0.314159274 0.600000000 0.00000000 0.00000000
+ 1.88495564 0.314159274 0.500000000 0.00000000 0.00000000
+ 2.51327443 0.314159274 0.500000000 0.00000000 0.00000000
+
+ -3.14159274 0.628318548 1.00000000 0.00000000 0.00000000
+ -2.51327419 0.628318548 1.00000000 0.00000000 0.00000000
+ -1.88495564 0.628318548 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.628318548 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.628318548 1.00000000 0.00000000 0.00000000
+ 0.00000000 0.628318548 1.00000000 0.00000000 0.00000000
+ 0.628318548 0.628318548 1.00000000 0.00000000 0.00000000
+ 1.25663686 0.628318548 1.00000000 0.00000000 0.00000000
+ 1.88495564 0.628318548 1.00000000 0.00000000 0.00000000
+ 2.51327443 0.628318548 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 0.942477822 1.00000000 0.00000000 0.00000000
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+ -1.88495564 0.942477822 1.00000000 0.00000000 0.00000000
+ -1.25663710 0.942477822 1.00000000 0.00000000 0.00000000
+ -0.628318548 0.942477822 1.00000000 0.00000000 0.00000000
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+
+ -3.14159274 1.25663710 0.300000012 0.00000000 0.00000000
+ -2.51327419 1.25663710 0.300000012 0.00000000 0.00000000
+ -1.88495564 1.25663710 0.300000012 0.00000000 0.00000000
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+ 1.88495564 1.25663710 0.300000012 0.00000000 0.00000000
+ 2.51327443 1.25663710 0.300000012 0.00000000 0.00000000
+
+ -3.14159274 1.57079637 1.00000000 0.00000000 0.00000000
+ -2.51327419 1.57079637 1.00000000 0.00000000 0.00000000
+ -1.88495564 1.57079637 1.00000000 0.00000000 0.00000000
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+ -0.628318548 1.57079637 1.00000000 0.00000000 0.00000000
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+ 0.628318548 1.57079637 1.00000000 0.00000000 0.00000000
+ 1.25663686 1.57079637 1.00000000 0.00000000 0.00000000
+ 1.88495564 1.57079637 1.00000000 0.00000000 0.00000000
+ 2.51327443 1.57079637 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 1.88495564 1.00000000 0.00000000 0.00000000
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+
+ -3.14159274 2.19911480 1.00000000 0.00000000 0.00000000
+ -2.51327419 2.19911480 1.00000000 0.00000000 0.00000000
+ -1.88495564 2.19911480 1.00000000 0.00000000 0.00000000
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+
+ -3.14159274 2.51327419 1.00000000 0.00000000 0.00000000
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+ -1.88495564 2.51327419 1.00000000 0.00000000 0.00000000
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+
+ -3.14159274 2.82743359 1.00000000 0.00000000 0.00000000
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+ 1.88495564 2.82743359 1.00000000 0.00000000 0.00000000
+ 2.51327443 2.82743359 1.00000000 0.00000000 0.00000000
+
+ -3.14159274 3.14159274 1.00000000 0.00000000 0.00000000
+ -2.51327419 3.14159274 1.00000000 0.00000000 0.00000000
+ -1.88495564 3.14159274 1.00000000 0.00000000 0.00000000
+ -1.25663710 3.14159274 1.00000000 0.00000000 0.00000000
+ -0.628318548 3.14159274 1.00000000 0.00000000 0.00000000
+ 0.00000000 3.14159274 1.00000000 0.00000000 0.00000000
+ 0.628318548 3.14159274 1.00000000 0.00000000 0.00000000
+ 1.25663686 3.14159274 1.00000000 0.00000000 0.00000000
+ 1.88495564 3.14159274 1.00000000 0.00000000 0.00000000
+ 2.51327443 3.14159274 1.00000000 0.00000000 0.00000000
diff --git a/regtest/basic/rt-ttmetad1/plumed.dat b/regtest/basic/rt-ttmetad1/plumed.dat
new file mode 100644
index 0000000000000000000000000000000000000000..774bdb7da969370e6468827227ab1e8d6830c983
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/plumed.dat
@@ -0,0 +1,113 @@
+RESTART
+
+phi: TORSION ATOMS=5,7,9,15 NOPBC
+psi: ANGLE ATOMS=7,9,15
+
+METAD ...
+ LABEL=metad1
+ ARG=phi,psi
+ SIGMA=0.20,0.20
+ HEIGHT=1.20
+ CALC_TRANSITION_BIAS
+ TRANSITIONWELL0=-1.0,1.0
+ TRANSITIONWELL1=1.0,2.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS-case1
+ GRID_RFILE=grid-case1
+ GRID_MIN=-pi,0
+ GRID_MAX=pi,pi
+ GRID_BIN=10,10
+... METAD
+
+METAD ...
+ LABEL=metad2
+ ARG=phi,psi
+ SIGMA=0.20,0.20
+ HEIGHT=1.20
+ CALC_TRANSITION_BIAS
+ TRANSITIONWELL0=-1.0,1.0
+ TRANSITIONWELL1=1.0,2.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS-case2
+ GRID_RFILE=grid-case2
+ GRID_MIN=-pi,0
+ GRID_MAX=pi,pi
+ GRID_BIN=10,10
+... METAD
+
+METAD ...
+ LABEL=metad3
+ ARG=phi,psi
+ SIGMA=0.20,0.20
+ HEIGHT=1.20
+ CALC_TRANSITION_BIAS
+ TRANSITIONWELL0=-1.0,1.0
+ TRANSITIONWELL1=1.0,2.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS-case3
+ GRID_RFILE=grid-case3
+ GRID_MIN=-pi,0
+ GRID_MAX=pi,pi
+ GRID_BIN=10,10
+... METAD
+
+METAD ...
+ LABEL=metad4
+ ARG=phi,psi
+ SIGMA=0.20,0.20
+ HEIGHT=1.20
+ CALC_TRANSITION_BIAS
+ TRANSITIONWELL0=-1.0,1.0
+ TRANSITIONWELL1=1.0,2.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS-case4
+ GRID_RFILE=grid-case4
+ GRID_MIN=-pi,0
+ GRID_MAX=pi,pi
+ GRID_BIN=10,10
+... METAD
+
+METAD ...
+ LABEL=metad5
+ ARG=phi,psi
+ SIGMA=0.20,0.20
+ HEIGHT=1.20
+ CALC_TRANSITION_BIAS
+ TRANSITIONWELL0=-1.0,1.0
+ TRANSITIONWELL1=1.0,2.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS-case5
+ GRID_RFILE=grid-case5
+ GRID_MIN=-pi,0
+ GRID_MAX=pi,pi
+ GRID_BIN=10,10
+... METAD
+
+METAD ...
+ LABEL=metad6
+ ARG=phi,psi
+ SIGMA=0.20,0.20
+ HEIGHT=1.20
+ CALC_TRANSITION_BIAS
+ TRANSITIONWELL0=-1.0,1.0
+ TRANSITIONWELL1=1.0,2.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS-case6
+ GRID_RFILE=grid-case6
+ GRID_MIN=-pi,0
+ GRID_MAX=pi,pi
+ GRID_BIN=10,10
+... METAD
+
+PRINT ...
+ ARG=phi,psi,metad1.bias,metad2.bias,metad3.bias,metad4.bias,metad5.bias,metad6.bias,metad1.transbias,metad2.transbias,metad3.transbias,metad4.transbias,metad5.transbias,metad6.transbias
+ STRIDE=500
+ FILE=COLVAR
+ FMT=%8.4f
+... PRINT
diff --git a/regtest/basic/rt-ttmetad1/traj.gro b/regtest/basic/rt-ttmetad1/traj.gro
new file mode 100644
index 0000000000000000000000000000000000000000..c1c387a0144ec8021b9e5b0453be534f2ca906e2
--- /dev/null
+++ b/regtest/basic/rt-ttmetad1/traj.gro
@@ -0,0 +1,525 @@
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 0.00000
+ 22
+ 1ACE HH31 1 1.474 1.585 1.200
+ 1ACE CH3 2 1.483 1.508 1.277
+ 1ACE HH32 3 1.476 1.561 1.372
+ 1ACE HH33 4 1.578 1.455 1.278
+ 1ACE C 5 1.353 1.428 1.279
+ 1ACE O 6 1.263 1.449 1.357
+ 2ALA N 7 1.343 1.328 1.191
+ 2ALA H 8 1.415 1.321 1.120
+ 2ALA CA 9 1.233 1.239 1.159
+ 2ALA HA 10 1.144 1.302 1.155
+ 2ALA CB 11 1.244 1.182 1.013
+ 2ALA HB1 12 1.341 1.136 0.992
+ 2ALA HB2 13 1.159 1.117 0.994
+ 2ALA HB3 14 1.242 1.265 0.942
+ 2ALA C 15 1.207 1.140 1.271
+ 2ALA O 16 1.214 1.017 1.241
+ 3NME N 17 1.191 1.177 1.398
+ 3NME H 18 1.192 1.275 1.421
+ 3NME CH3 19 1.189 1.086 1.518
+ 3NME HH31 20 1.170 0.983 1.487
+ 3NME HH32 21 1.283 1.087 1.574
+ 3NME HH33 22 1.108 1.127 1.578
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 1.00000
+ 22
+ 1ACE HH31 1 1.480 1.571 1.214
+ 1ACE CH3 2 1.481 1.493 1.289
+ 1ACE HH32 3 1.502 1.528 1.390
+ 1ACE HH33 4 1.551 1.417 1.255
+ 1ACE C 5 1.344 1.432 1.275
+ 1ACE O 6 1.250 1.462 1.345
+ 2ALA N 7 1.342 1.327 1.193
+ 2ALA H 8 1.430 1.313 1.144
+ 2ALA CA 9 1.233 1.244 1.166
+ 2ALA HA 10 1.144 1.307 1.173
+ 2ALA CB 11 1.240 1.189 1.017
+ 2ALA HB1 12 1.327 1.124 1.000
+ 2ALA HB2 13 1.150 1.128 1.005
+ 2ALA HB3 14 1.251 1.267 0.941
+ 2ALA C 15 1.221 1.133 1.271
+ 2ALA O 16 1.217 1.015 1.238
+ 3NME N 17 1.204 1.174 1.395
+ 3NME H 18 1.200 1.275 1.398
+ 3NME CH3 19 1.188 1.089 1.516
+ 3NME HH31 20 1.083 1.086 1.543
+ 3NME HH32 21 1.233 0.990 1.511
+ 3NME HH33 22 1.241 1.141 1.596
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 2.00000
+ 22
+ 1ACE HH31 1 1.532 1.520 1.209
+ 1ACE CH3 2 1.478 1.493 1.300
+ 1ACE HH32 3 1.465 1.586 1.356
+ 1ACE HH33 4 1.548 1.426 1.350
+ 1ACE C 5 1.352 1.423 1.279
+ 1ACE O 6 1.252 1.461 1.340
+ 2ALA N 7 1.351 1.326 1.190
+ 2ALA H 8 1.442 1.293 1.160
+ 2ALA CA 9 1.232 1.244 1.160
+ 2ALA HA 10 1.146 1.310 1.151
+ 2ALA CB 11 1.241 1.190 1.016
+ 2ALA HB1 12 1.333 1.132 1.008
+ 2ALA HB2 13 1.160 1.123 0.986
+ 2ALA HB3 14 1.242 1.280 0.955
+ 2ALA C 15 1.203 1.138 1.270
+ 2ALA O 16 1.161 1.021 1.240
+ 3NME N 17 1.230 1.171 1.396
+ 3NME H 18 1.257 1.266 1.417
+ 3NME CH3 19 1.217 1.090 1.512
+ 3NME HH31 20 1.144 1.011 1.493
+ 3NME HH32 21 1.307 1.029 1.526
+ 3NME HH33 22 1.212 1.146 1.605
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 3.00000
+ 22
+ 1ACE HH31 1 1.439 1.582 1.175
+ 1ACE CH3 2 1.474 1.516 1.254
+ 1ACE HH32 3 1.480 1.585 1.338
+ 1ACE HH33 4 1.569 1.465 1.242
+ 1ACE C 5 1.364 1.419 1.280
+ 1ACE O 6 1.277 1.446 1.367
+ 2ALA N 7 1.358 1.323 1.194
+ 2ALA H 8 1.443 1.313 1.140
+ 2ALA CA 9 1.235 1.243 1.164
+ 2ALA HA 10 1.150 1.310 1.170
+ 2ALA CB 11 1.240 1.197 1.019
+ 2ALA HB1 12 1.316 1.119 1.016
+ 2ALA HB2 13 1.145 1.157 0.982
+ 2ALA HB3 14 1.279 1.276 0.955
+ 2ALA C 15 1.201 1.137 1.272
+ 2ALA O 16 1.172 1.021 1.232
+ 3NME N 17 1.218 1.166 1.402
+ 3NME H 18 1.240 1.259 1.434
+ 3NME CH3 19 1.186 1.086 1.518
+ 3NME HH31 20 1.225 0.984 1.527
+ 3NME HH32 21 1.193 1.134 1.616
+ 3NME HH33 22 1.081 1.058 1.509
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 4.00000
+ 22
+ 1ACE HH31 1 1.549 1.508 1.196
+ 1ACE CH3 2 1.500 1.486 1.290
+ 1ACE HH32 3 1.487 1.571 1.357
+ 1ACE HH33 4 1.563 1.415 1.343
+ 1ACE C 5 1.362 1.425 1.270
+ 1ACE O 6 1.265 1.465 1.340
+ 2ALA N 7 1.349 1.324 1.182
+ 2ALA H 8 1.432 1.287 1.138
+ 2ALA CA 9 1.221 1.249 1.168
+ 2ALA HA 10 1.138 1.318 1.184
+ 2ALA CB 11 1.201 1.194 1.025
+ 2ALA HB1 12 1.276 1.117 1.005
+ 2ALA HB2 13 1.096 1.165 1.014
+ 2ALA HB3 14 1.229 1.265 0.947
+ 2ALA C 15 1.217 1.141 1.275
+ 2ALA O 16 1.234 1.024 1.243
+ 3NME N 17 1.183 1.174 1.400
+ 3NME H 18 1.184 1.274 1.412
+ 3NME CH3 19 1.187 1.078 1.509
+ 3NME HH31 20 1.248 0.990 1.490
+ 3NME HH32 21 1.220 1.120 1.604
+ 3NME HH33 22 1.088 1.035 1.527
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 5.00000
+ 22
+ 1ACE HH31 1 1.449 1.585 1.168
+ 1ACE CH3 2 1.479 1.518 1.248
+ 1ACE HH32 3 1.523 1.577 1.328
+ 1ACE HH33 4 1.565 1.461 1.213
+ 1ACE C 5 1.364 1.422 1.284
+ 1ACE O 6 1.305 1.438 1.389
+ 2ALA N 7 1.347 1.326 1.187
+ 2ALA H 8 1.423 1.328 1.122
+ 2ALA CA 9 1.226 1.241 1.162
+ 2ALA HA 10 1.139 1.308 1.162
+ 2ALA CB 11 1.236 1.193 1.023
+ 2ALA HB1 12 1.314 1.117 1.012
+ 2ALA HB2 13 1.137 1.167 0.986
+ 2ALA HB3 14 1.273 1.278 0.966
+ 2ALA C 15 1.195 1.133 1.268
+ 2ALA O 16 1.173 1.016 1.239
+ 3NME N 17 1.204 1.175 1.393
+ 3NME H 18 1.211 1.275 1.403
+ 3NME CH3 19 1.188 1.090 1.513
+ 3NME HH31 20 1.089 1.044 1.509
+ 3NME HH32 21 1.267 1.014 1.509
+ 3NME HH33 22 1.189 1.145 1.607
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 6.00000
+ 22
+ 1ACE HH31 1 1.517 1.511 1.181
+ 1ACE CH3 2 1.490 1.488 1.284
+ 1ACE HH32 3 1.482 1.582 1.339
+ 1ACE HH33 4 1.569 1.421 1.316
+ 1ACE C 5 1.359 1.414 1.282
+ 1ACE O 6 1.272 1.447 1.358
+ 2ALA N 7 1.351 1.320 1.186
+ 2ALA H 8 1.434 1.297 1.133
+ 2ALA CA 9 1.220 1.251 1.159
+ 2ALA HA 10 1.139 1.323 1.167
+ 2ALA CB 11 1.220 1.194 1.018
+ 2ALA HB1 12 1.298 1.120 1.003
+ 2ALA HB2 13 1.120 1.158 0.994
+ 2ALA HB3 14 1.224 1.286 0.960
+ 2ALA C 15 1.201 1.139 1.270
+ 2ALA O 16 1.190 1.022 1.239
+ 3NME N 17 1.203 1.178 1.393
+ 3NME H 18 1.207 1.277 1.409
+ 3NME CH3 19 1.211 1.102 1.515
+ 3NME HH31 20 1.111 1.064 1.534
+ 3NME HH32 21 1.275 1.017 1.492
+ 3NME HH33 22 1.264 1.151 1.597
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 7.00000
+ 22
+ 1ACE HH31 1 1.483 1.590 1.185
+ 1ACE CH3 2 1.505 1.501 1.245
+ 1ACE HH32 3 1.538 1.533 1.344
+ 1ACE HH33 4 1.580 1.430 1.209
+ 1ACE C 5 1.379 1.418 1.267
+ 1ACE O 6 1.298 1.443 1.349
+ 2ALA N 7 1.360 1.320 1.187
+ 2ALA H 8 1.426 1.297 1.114
+ 2ALA CA 9 1.224 1.253 1.180
+ 2ALA HA 10 1.147 1.326 1.205
+ 2ALA CB 11 1.174 1.215 1.037
+ 2ALA HB1 12 1.245 1.152 0.983
+ 2ALA HB2 13 1.084 1.154 1.032
+ 2ALA HB3 14 1.153 1.311 0.992
+ 2ALA C 15 1.212 1.141 1.280
+ 2ALA O 16 1.219 1.022 1.244
+ 3NME N 17 1.191 1.176 1.408
+ 3NME H 18 1.207 1.275 1.423
+ 3NME CH3 19 1.162 1.068 1.509
+ 3NME HH31 20 1.229 0.982 1.503
+ 3NME HH32 21 1.162 1.109 1.610
+ 3NME HH33 22 1.056 1.044 1.499
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 8.00000
+ 22
+ 1ACE HH31 1 1.576 1.425 1.169
+ 1ACE CH3 2 1.523 1.455 1.260
+ 1ACE HH32 3 1.547 1.556 1.294
+ 1ACE HH33 4 1.566 1.393 1.338
+ 1ACE C 5 1.385 1.422 1.255
+ 1ACE O 6 1.308 1.499 1.305
+ 2ALA N 7 1.346 1.311 1.189
+ 2ALA H 8 1.419 1.248 1.159
+ 2ALA CA 9 1.210 1.260 1.193
+ 2ALA HA 10 1.139 1.326 1.242
+ 2ALA CB 11 1.152 1.252 1.051
+ 2ALA HB1 12 1.230 1.210 0.987
+ 2ALA HB2 13 1.066 1.185 1.052
+ 2ALA HB3 14 1.127 1.354 1.024
+ 2ALA C 15 1.206 1.136 1.282
+ 2ALA O 16 1.195 1.023 1.229
+ 3NME N 17 1.210 1.152 1.420
+ 3NME H 18 1.221 1.243 1.463
+ 3NME CH3 19 1.185 1.048 1.518
+ 3NME HH31 20 1.195 0.948 1.475
+ 3NME HH32 21 1.261 1.070 1.593
+ 3NME HH33 22 1.088 1.064 1.565
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 9.00000
+ 22
+ 1ACE HH31 1 1.515 1.474 1.040
+ 1ACE CH3 2 1.535 1.461 1.147
+ 1ACE HH32 3 1.561 1.560 1.184
+ 1ACE HH33 4 1.612 1.386 1.165
+ 1ACE C 5 1.406 1.430 1.217
+ 1ACE O 6 1.361 1.502 1.307
+ 2ALA N 7 1.345 1.316 1.190
+ 2ALA H 8 1.384 1.254 1.121
+ 2ALA CA 9 1.217 1.277 1.242
+ 2ALA HA 10 1.187 1.348 1.319
+ 2ALA CB 11 1.111 1.278 1.134
+ 2ALA HB1 12 1.129 1.198 1.062
+ 2ALA HB2 13 1.018 1.269 1.189
+ 2ALA HB3 14 1.121 1.372 1.079
+ 2ALA C 15 1.217 1.133 1.309
+ 2ALA O 16 1.293 1.044 1.265
+ 3NME N 17 1.132 1.116 1.408
+ 3NME H 18 1.076 1.195 1.437
+ 3NME CH3 19 1.112 1.003 1.490
+ 3NME HH31 20 1.156 0.910 1.456
+ 3NME HH32 21 1.153 1.026 1.588
+ 3NME HH33 22 1.005 0.985 1.500
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 10.00000
+ 22
+ 1ACE HH31 1 1.536 1.485 1.135
+ 1ACE CH3 2 1.521 1.460 1.240
+ 1ACE HH32 3 1.528 1.557 1.289
+ 1ACE HH33 4 1.602 1.397 1.276
+ 1ACE C 5 1.385 1.401 1.261
+ 1ACE O 6 1.341 1.416 1.373
+ 2ALA N 7 1.322 1.332 1.167
+ 2ALA H 8 1.364 1.316 1.076
+ 2ALA CA 9 1.190 1.273 1.177
+ 2ALA HA 10 1.125 1.352 1.216
+ 2ALA CB 11 1.134 1.230 1.038
+ 2ALA HB1 12 1.167 1.128 1.016
+ 2ALA HB2 13 1.026 1.238 1.046
+ 2ALA HB3 14 1.174 1.287 0.953
+ 2ALA C 15 1.183 1.157 1.283
+ 2ALA O 16 1.111 1.061 1.259
+ 3NME N 17 1.264 1.157 1.396
+ 3NME H 18 1.320 1.241 1.405
+ 3NME CH3 19 1.264 1.070 1.510
+ 3NME HH31 20 1.163 1.057 1.548
+ 3NME HH32 21 1.311 0.974 1.487
+ 3NME HH33 22 1.326 1.109 1.592
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 11.00000
+ 22
+ 1ACE HH31 1 1.607 1.359 1.178
+ 1ACE CH3 2 1.535 1.442 1.176
+ 1ACE HH32 3 1.521 1.470 1.072
+ 1ACE HH33 4 1.569 1.533 1.224
+ 1ACE C 5 1.402 1.412 1.242
+ 1ACE O 6 1.368 1.454 1.350
+ 2ALA N 7 1.319 1.332 1.177
+ 2ALA H 8 1.363 1.279 1.103
+ 2ALA CA 9 1.194 1.289 1.231
+ 2ALA HA 10 1.153 1.355 1.308
+ 2ALA CB 11 1.092 1.300 1.113
+ 2ALA HB1 12 1.137 1.243 1.032
+ 2ALA HB2 13 1.001 1.243 1.131
+ 2ALA HB3 14 1.070 1.405 1.095
+ 2ALA C 15 1.198 1.143 1.290
+ 2ALA O 16 1.237 1.057 1.213
+ 3NME N 17 1.171 1.126 1.422
+ 3NME H 18 1.164 1.213 1.472
+ 3NME CH3 19 1.200 1.009 1.496
+ 3NME HH31 20 1.118 0.938 1.493
+ 3NME HH32 21 1.284 0.953 1.454
+ 3NME HH33 22 1.230 1.031 1.598
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 12.00000
+ 22
+ 1ACE HH31 1 1.491 1.569 1.138
+ 1ACE CH3 2 1.511 1.462 1.134
+ 1ACE HH32 3 1.614 1.449 1.166
+ 1ACE HH33 4 1.495 1.444 1.028
+ 1ACE C 5 1.416 1.394 1.229
+ 1ACE O 6 1.445 1.392 1.345
+ 2ALA N 7 1.299 1.357 1.181
+ 2ALA H 8 1.278 1.358 1.082
+ 2ALA CA 9 1.196 1.301 1.267
+ 2ALA HA 10 1.185 1.364 1.355
+ 2ALA CB 11 1.063 1.319 1.182
+ 2ALA HB1 12 1.057 1.248 1.100
+ 2ALA HB2 13 0.976 1.288 1.240
+ 2ALA HB3 14 1.037 1.423 1.161
+ 2ALA C 15 1.226 1.161 1.304
+ 2ALA O 16 1.317 1.094 1.258
+ 3NME N 17 1.135 1.110 1.387
+ 3NME H 18 1.064 1.174 1.419
+ 3NME CH3 19 1.121 0.972 1.429
+ 3NME HH31 20 1.163 0.900 1.358
+ 3NME HH32 21 1.177 0.954 1.520
+ 3NME HH33 22 1.016 0.942 1.428
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 13.00000
+ 22
+ 1ACE HH31 1 1.528 1.537 1.077
+ 1ACE CH3 2 1.543 1.448 1.137
+ 1ACE HH32 3 1.634 1.463 1.195
+ 1ACE HH33 4 1.560 1.362 1.072
+ 1ACE C 5 1.421 1.428 1.229
+ 1ACE O 6 1.396 1.520 1.301
+ 2ALA N 7 1.355 1.314 1.219
+ 2ALA H 8 1.385 1.241 1.156
+ 2ALA CA 9 1.249 1.276 1.311
+ 2ALA HA 10 1.297 1.288 1.409
+ 2ALA CB 11 1.122 1.359 1.284
+ 2ALA HB1 12 1.072 1.325 1.193
+ 2ALA HB2 13 1.053 1.352 1.367
+ 2ALA HB3 14 1.153 1.463 1.275
+ 2ALA C 15 1.204 1.131 1.290
+ 2ALA O 16 1.225 1.070 1.185
+ 3NME N 17 1.131 1.077 1.382
+ 3NME H 18 1.104 1.132 1.463
+ 3NME CH3 19 1.083 0.939 1.380
+ 3NME HH31 20 1.012 0.925 1.298
+ 3NME HH32 21 1.168 0.871 1.372
+ 3NME HH33 22 1.036 0.915 1.475
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 14.00000
+ 22
+ 1ACE HH31 1 1.543 1.468 1.123
+ 1ACE CH3 2 1.548 1.443 1.229
+ 1ACE HH32 3 1.566 1.540 1.276
+ 1ACE HH33 4 1.634 1.382 1.257
+ 1ACE C 5 1.420 1.385 1.285
+ 1ACE O 6 1.412 1.375 1.404
+ 2ALA N 7 1.324 1.361 1.200
+ 2ALA H 8 1.345 1.354 1.101
+ 2ALA CA 9 1.189 1.323 1.244
+ 2ALA HA 10 1.163 1.394 1.323
+ 2ALA CB 11 1.094 1.344 1.125
+ 2ALA HB1 12 1.098 1.270 1.045
+ 2ALA HB2 13 0.995 1.352 1.170
+ 2ALA HB3 14 1.120 1.440 1.079
+ 2ALA C 15 1.166 1.169 1.284
+ 2ALA O 16 1.055 1.145 1.330
+ 3NME N 17 1.263 1.077 1.279
+ 3NME H 18 1.356 1.102 1.247
+ 3NME CH3 19 1.246 0.942 1.335
+ 3NME HH31 20 1.142 0.911 1.345
+ 3NME HH32 21 1.293 0.868 1.270
+ 3NME HH33 22 1.292 0.934 1.434
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 15.00000
+ 22
+ 1ACE HH31 1 1.508 1.417 1.043
+ 1ACE CH3 2 1.539 1.448 1.143
+ 1ACE HH32 3 1.565 1.553 1.146
+ 1ACE HH33 4 1.630 1.395 1.169
+ 1ACE C 5 1.438 1.410 1.253
+ 1ACE O 6 1.429 1.471 1.356
+ 2ALA N 7 1.348 1.327 1.217
+ 2ALA H 8 1.362 1.285 1.126
+ 2ALA CA 9 1.233 1.289 1.298
+ 2ALA HA 10 1.269 1.295 1.401
+ 2ALA CB 11 1.107 1.379 1.286
+ 2ALA HB1 12 1.057 1.360 1.191
+ 2ALA HB2 13 1.034 1.369 1.366
+ 2ALA HB3 14 1.141 1.482 1.282
+ 2ALA C 15 1.192 1.141 1.266
+ 2ALA O 16 1.220 1.089 1.156
+ 3NME N 17 1.131 1.075 1.364
+ 3NME H 18 1.117 1.126 1.450
+ 3NME CH3 19 1.090 0.931 1.376
+ 3NME HH31 20 1.156 0.880 1.446
+ 3NME HH32 21 0.996 0.929 1.431
+ 3NME HH33 22 1.090 0.874 1.283
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 16.00000
+ 22
+ 1ACE HH31 1 1.587 1.386 1.166
+ 1ACE CH3 2 1.554 1.425 1.262
+ 1ACE HH32 3 1.559 1.534 1.266
+ 1ACE HH33 4 1.627 1.390 1.335
+ 1ACE C 5 1.417 1.372 1.300
+ 1ACE O 6 1.390 1.364 1.421
+ 2ALA N 7 1.334 1.344 1.205
+ 2ALA H 8 1.365 1.367 1.111
+ 2ALA CA 9 1.190 1.324 1.235
+ 2ALA HA 10 1.160 1.386 1.319
+ 2ALA CB 11 1.105 1.363 1.112
+ 2ALA HB1 12 1.129 1.297 1.029
+ 2ALA HB2 13 0.999 1.351 1.131
+ 2ALA HB3 14 1.125 1.467 1.088
+ 2ALA C 15 1.162 1.180 1.282
+ 2ALA O 16 1.054 1.128 1.258
+ 3NME N 17 1.261 1.106 1.318
+ 3NME H 18 1.349 1.152 1.336
+ 3NME CH3 19 1.250 0.960 1.324
+ 3NME HH31 20 1.264 0.908 1.229
+ 3NME HH32 21 1.322 0.926 1.399
+ 3NME HH33 22 1.153 0.923 1.357
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 17.00000
+ 22
+ 1ACE HH31 1 1.614 1.382 1.173
+ 1ACE CH3 2 1.559 1.432 1.253
+ 1ACE HH32 3 1.547 1.532 1.213
+ 1ACE HH33 4 1.625 1.444 1.339
+ 1ACE C 5 1.426 1.380 1.288
+ 1ACE O 6 1.411 1.348 1.406
+ 2ALA N 7 1.325 1.370 1.200
+ 2ALA H 8 1.341 1.388 1.102
+ 2ALA CA 9 1.189 1.318 1.239
+ 2ALA HA 10 1.170 1.358 1.338
+ 2ALA CB 11 1.084 1.388 1.158
+ 2ALA HB1 12 1.113 1.369 1.055
+ 2ALA HB2 13 0.994 1.336 1.189
+ 2ALA HB3 14 1.075 1.493 1.186
+ 2ALA C 15 1.170 1.163 1.252
+ 2ALA O 16 1.097 1.103 1.171
+ 3NME N 17 1.235 1.099 1.349
+ 3NME H 18 1.305 1.153 1.399
+ 3NME CH3 19 1.220 0.964 1.393
+ 3NME HH31 20 1.315 0.912 1.406
+ 3NME HH32 21 1.168 0.953 1.489
+ 3NME HH33 22 1.178 0.897 1.318
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 18.00000
+ 22
+ 1ACE HH31 1 1.555 1.419 1.126
+ 1ACE CH3 2 1.554 1.431 1.235
+ 1ACE HH32 3 1.554 1.535 1.267
+ 1ACE HH33 4 1.638 1.381 1.283
+ 1ACE C 5 1.423 1.378 1.292
+ 1ACE O 6 1.416 1.347 1.409
+ 2ALA N 7 1.322 1.351 1.211
+ 2ALA H 8 1.350 1.370 1.115
+ 2ALA CA 9 1.185 1.318 1.251
+ 2ALA HA 10 1.171 1.358 1.352
+ 2ALA CB 11 1.091 1.400 1.149
+ 2ALA HB1 12 1.059 1.346 1.060
+ 2ALA HB2 13 1.008 1.443 1.205
+ 2ALA HB3 14 1.154 1.480 1.109
+ 2ALA C 15 1.163 1.166 1.255
+ 2ALA O 16 1.060 1.108 1.214
+ 3NME N 17 1.255 1.102 1.328
+ 3NME H 18 1.335 1.159 1.354
+ 3NME CH3 19 1.246 0.964 1.369
+ 3NME HH31 20 1.154 0.913 1.344
+ 3NME HH32 21 1.323 0.899 1.327
+ 3NME HH33 22 1.251 0.953 1.477
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 19.00000
+ 22
+ 1ACE HH31 1 1.559 1.326 1.133
+ 1ACE CH3 2 1.552 1.413 1.200
+ 1ACE HH32 3 1.538 1.504 1.142
+ 1ACE HH33 4 1.631 1.428 1.273
+ 1ACE C 5 1.426 1.375 1.280
+ 1ACE O 6 1.428 1.345 1.398
+ 2ALA N 7 1.319 1.363 1.209
+ 2ALA H 8 1.322 1.382 1.110
+ 2ALA CA 9 1.191 1.329 1.265
+ 2ALA HA 10 1.186 1.364 1.368
+ 2ALA CB 11 1.075 1.391 1.178
+ 2ALA HB1 12 1.098 1.383 1.072
+ 2ALA HB2 13 0.980 1.348 1.211
+ 2ALA HB3 14 1.066 1.499 1.192
+ 2ALA C 15 1.169 1.174 1.275
+ 2ALA O 16 1.086 1.118 1.203
+ 3NME N 17 1.233 1.105 1.363
+ 3NME H 18 1.312 1.150 1.405
+ 3NME CH3 19 1.242 0.956 1.350
+ 3NME HH31 20 1.219 0.899 1.440
+ 3NME HH32 21 1.165 0.918 1.284
+ 3NME HH33 22 1.333 0.921 1.301
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 20.00000
+ 22
+ 1ACE HH31 1 1.622 1.459 1.287
+ 1ACE CH3 2 1.546 1.434 1.214
+ 1ACE HH32 3 1.578 1.365 1.135
+ 1ACE HH33 4 1.509 1.531 1.180
+ 1ACE C 5 1.430 1.358 1.283
+ 1ACE O 6 1.444 1.310 1.394
+ 2ALA N 7 1.315 1.370 1.215
+ 2ALA H 8 1.323 1.427 1.132
+ 2ALA CA 9 1.178 1.334 1.258
+ 2ALA HA 10 1.163 1.376 1.357
+ 2ALA CB 11 1.079 1.393 1.158
+ 2ALA HB1 12 1.096 1.348 1.060
+ 2ALA HB2 13 0.979 1.367 1.192
+ 2ALA HB3 14 1.087 1.501 1.165
+ 2ALA C 15 1.163 1.177 1.270
+ 2ALA O 16 1.073 1.114 1.216
+ 3NME N 17 1.249 1.110 1.347
+ 3NME H 18 1.324 1.165 1.388
+ 3NME CH3 19 1.242 0.964 1.360
+ 3NME HH31 20 1.325 0.920 1.416
+ 3NME HH32 21 1.151 0.938 1.414
+ 3NME HH33 22 1.221 0.913 1.266
+ 10.00000 10.00000 10.00000
diff --git a/regtest/basic/rt-ttmetad2/COLVAR.reference b/regtest/basic/rt-ttmetad2/COLVAR.reference
new file mode 100644
index 0000000000000000000000000000000000000000..130861465f45b489441cbb32562222d832eaab0b
--- /dev/null
+++ b/regtest/basic/rt-ttmetad2/COLVAR.reference
@@ -0,0 +1,22 @@
+#! FIELDS time psi metadnp1.bias metadnp1thresh.bias metadnp1threshhalf.bias metadnp1.transbias metadnp1thresh.transbias metadnp1threshhalf.transbias
+ 0.000000 1.9470 1.0000 1.0000 1.0000 0.3000 0.3000 0.3000
+ 1.000000 1.9381 1.0000 1.0000 1.0000 0.4970 0.5134 0.5136
+ 2.000000 1.9663 2.0389 2.1257 2.1265 0.6361 0.6631 0.6644
+ 3.000000 1.9885 2.9669 3.1244 3.1327 0.7411 0.7757 0.7787
+ 4.000000 1.8901 3.7717 3.9869 4.0082 0.9904 1.0000 1.0000
+ 5.000000 2.0306 4.4170 4.6751 4.7138 1.0000 1.0000 1.0000
+ 6.000000 1.8776 5.1963 5.5152 5.5855 1.0000 1.0000 1.0000
+ 7.000000 1.9488 6.2490 6.6541 6.7671 1.0000 1.0000 1.0000
+ 8.000000 1.9025 6.9488 7.4128 7.5611 1.0000 1.0000 1.0000
+ 9.000000 1.9813 7.6647 8.1885 8.3708 1.0000 1.0000 1.0000
+ 10.000000 1.9684 8.5305 9.1263 9.3479 1.0000 1.0000 1.0000
+ 11.000000 1.9807 9.2377 9.8929 10.1491 1.0000 1.0000 1.0000
+ 12.000000 1.9486 10.1740 10.9067 11.2045 1.0000 1.0000 1.0000
+ 13.000000 1.9547 10.9540 11.7519 12.0867 1.0000 1.0000 1.0000
+ 14.000000 2.0415 10.6519 11.4280 11.7630 1.0000 1.0000 1.0000
+ 15.000000 1.9166 12.3389 13.2526 13.6532 1.0000 1.0000 1.0000
+ 16.000000 1.9433 13.2603 14.2507 14.6938 1.0000 1.0000 1.0000
+ 17.000000 2.0625 12.2260 13.1349 13.5500 1.0000 1.0000 1.0000
+ 18.000000 1.9433 14.7191 15.8312 16.3429 1.0000 1.0000 1.0000
+ 19.000000 1.9642 15.4791 16.6549 17.2034 1.0000 1.0000 1.0000
+ 20.000000 1.9296 16.2438 17.4833 18.0669 1.0000 1.0000 1.0000
diff --git a/regtest/basic/rt-ttmetad2/HILLS-thresh.reference b/regtest/basic/rt-ttmetad2/HILLS-thresh.reference
new file mode 100644
index 0000000000000000000000000000000000000000..c8c61bde6fd74e24ba8d4f083d21f892d09edbc2
--- /dev/null
+++ b/regtest/basic/rt-ttmetad2/HILLS-thresh.reference
@@ -0,0 +1,22 @@
+#! FIELDS time psi sigma_psi height biasf
+#! SET multivariate false
+ 1.00000 1.93813 0.20000 1.15284 -1.00000
+ 2.00000 1.96635 0.20000 1.05830 -1.00000
+ 3.00000 1.98846 0.20000 0.99666 -1.00000
+ 4.00000 1.89011 0.20000 0.95266 -1.00000
+ 5.00000 2.03063 0.20000 0.87075 -1.00000
+ 6.00000 1.87763 0.20000 0.87075 -1.00000
+ 7.00000 1.94875 0.20000 0.87075 -1.00000
+ 8.00000 1.90246 0.20000 0.87075 -1.00000
+ 9.00000 1.98135 0.20000 0.87075 -1.00000
+ 10.00000 1.96844 0.20000 0.87075 -1.00000
+ 11.00000 1.98070 0.20000 0.87075 -1.00000
+ 12.00000 1.94862 0.20000 0.87075 -1.00000
+ 13.00000 1.95473 0.20000 0.87075 -1.00000
+ 14.00000 2.04152 0.20000 0.87075 -1.00000
+ 15.00000 1.91658 0.20000 0.87075 -1.00000
+ 16.00000 1.94328 0.20000 0.87075 -1.00000
+ 17.00000 2.06246 0.20000 0.87075 -1.00000
+ 18.00000 1.94326 0.20000 0.87075 -1.00000
+ 19.00000 1.96416 0.20000 0.87075 -1.00000
+ 20.00000 1.92964 0.20000 0.87075 -1.00000
diff --git a/regtest/basic/rt-ttmetad2/HILLS-threshhalf.reference b/regtest/basic/rt-ttmetad2/HILLS-threshhalf.reference
new file mode 100644
index 0000000000000000000000000000000000000000..d8807097e2a576abeaba25688ee853678a2dd7df
--- /dev/null
+++ b/regtest/basic/rt-ttmetad2/HILLS-threshhalf.reference
@@ -0,0 +1,22 @@
+#! FIELDS time psi sigma_psi height biasf
+#! SET multivariate false
+ 1.00000 1.93813 0.20000 1.15375 -1.00000
+ 2.00000 1.96635 0.20000 1.06598 -1.00000
+ 3.00000 1.98846 0.20000 1.01166 -1.00000
+ 4.00000 1.89011 0.20000 0.97403 -1.00000
+ 5.00000 2.03063 0.20000 0.90859 -1.00000
+ 6.00000 1.87763 0.20000 0.90859 -1.00000
+ 7.00000 1.94875 0.20000 0.90859 -1.00000
+ 8.00000 1.90246 0.20000 0.90859 -1.00000
+ 9.00000 1.98135 0.20000 0.90859 -1.00000
+ 10.00000 1.96844 0.20000 0.90859 -1.00000
+ 11.00000 1.98070 0.20000 0.90859 -1.00000
+ 12.00000 1.94862 0.20000 0.90859 -1.00000
+ 13.00000 1.95473 0.20000 0.90859 -1.00000
+ 14.00000 2.04152 0.20000 0.90859 -1.00000
+ 15.00000 1.91658 0.20000 0.90859 -1.00000
+ 16.00000 1.94328 0.20000 0.90859 -1.00000
+ 17.00000 2.06246 0.20000 0.90859 -1.00000
+ 18.00000 1.94326 0.20000 0.90859 -1.00000
+ 19.00000 1.96416 0.20000 0.90859 -1.00000
+ 20.00000 1.92964 0.20000 0.90859 -1.00000
diff --git a/regtest/basic/rt-ttmetad2/HILLS.reference b/regtest/basic/rt-ttmetad2/HILLS.reference
new file mode 100644
index 0000000000000000000000000000000000000000..8128fb7a19ba8744bb75cb2828cf7b47d0551eee
--- /dev/null
+++ b/regtest/basic/rt-ttmetad2/HILLS.reference
@@ -0,0 +1,22 @@
+#! FIELDS time psi sigma_psi height biasf
+#! SET multivariate false
+ 1.00000 1.93813 0.20000 1.06401 -1.00000
+ 2.00000 1.96635 0.20000 0.98322 -1.00000
+ 3.00000 1.98846 0.20000 0.92990 -1.00000
+ 4.00000 1.89011 0.20000 0.89154 -1.00000
+ 5.00000 2.03063 0.20000 0.80676 -1.00000
+ 6.00000 1.87763 0.20000 0.80365 -1.00000
+ 7.00000 1.94875 0.20000 0.80365 -1.00000
+ 8.00000 1.90246 0.20000 0.80365 -1.00000
+ 9.00000 1.98135 0.20000 0.80365 -1.00000
+ 10.00000 1.96844 0.20000 0.80365 -1.00000
+ 11.00000 1.98070 0.20000 0.80365 -1.00000
+ 12.00000 1.94862 0.20000 0.80365 -1.00000
+ 13.00000 1.95473 0.20000 0.80365 -1.00000
+ 14.00000 2.04152 0.20000 0.80365 -1.00000
+ 15.00000 1.91658 0.20000 0.80365 -1.00000
+ 16.00000 1.94328 0.20000 0.80365 -1.00000
+ 17.00000 2.06246 0.20000 0.80365 -1.00000
+ 18.00000 1.94326 0.20000 0.80365 -1.00000
+ 19.00000 1.96416 0.20000 0.80365 -1.00000
+ 20.00000 1.92964 0.20000 0.80365 -1.00000
diff --git a/regtest/basic/rt-ttmetad2/Makefile b/regtest/basic/rt-ttmetad2/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..3703b27cea227aa053fb6d1d73f861e4384dbcee
--- /dev/null
+++ b/regtest/basic/rt-ttmetad2/Makefile
@@ -0,0 +1 @@
+include ../../scripts/test.make
diff --git a/regtest/basic/rt-ttmetad2/config b/regtest/basic/rt-ttmetad2/config
new file mode 100644
index 0000000000000000000000000000000000000000..ce858d0c5a1fc8ff0fa3f73d5836edaf432c82e8
--- /dev/null
+++ b/regtest/basic/rt-ttmetad2/config
@@ -0,0 +1,3 @@
+type=driver
+# this is to test a different name
+arg="--plumed plumed.dat --trajectory-stride 500 --timestep 0.002 --igro traj.gro"
diff --git a/regtest/basic/rt-ttmetad2/grid-nonperiodic b/regtest/basic/rt-ttmetad2/grid-nonperiodic
new file mode 100644
index 0000000000000000000000000000000000000000..40821efbfa733fccb00d6d7735fb6e89df469a87
--- /dev/null
+++ b/regtest/basic/rt-ttmetad2/grid-nonperiodic
@@ -0,0 +1,16 @@
+#! FIELDS psi metadnp1.bias der_psi
+#! SET min_psi 0
+#! SET max_psi pi
+#! SET nbins_psi 11
+#! SET periodic_psi false
+ 0.000000000 1.00000 0.00000
+ 0.314159265 0.50000 0.00000
+ 0.628318531 1.00000 0.00000
+ 0.942477796 1.00000 0.00000
+ 1.256637061 1.00000 0.00000
+ 1.570796327 0.30000 0.00000
+ 1.884955592 1.00000 0.00000
+ 2.199114858 1.00000 0.00000
+ 2.513274123 1.00000 0.00000
+ 2.827433388 1.00000 0.00000
+ 3.141592654 1.00000 0.00000
diff --git a/regtest/basic/rt-ttmetad2/grid-nonperiodic-thresh b/regtest/basic/rt-ttmetad2/grid-nonperiodic-thresh
new file mode 100644
index 0000000000000000000000000000000000000000..38b1a0b6e0b3d166d104e2048daecf7625085817
--- /dev/null
+++ b/regtest/basic/rt-ttmetad2/grid-nonperiodic-thresh
@@ -0,0 +1,16 @@
+#! FIELDS psi metadnp1thresh.bias der_psi
+#! SET min_psi 0
+#! SET max_psi pi
+#! SET nbins_psi 11
+#! SET periodic_psi false
+ 0.000000000 1.00000 0.00000
+ 0.314159265 0.50000 0.00000
+ 0.628318531 1.00000 0.00000
+ 0.942477796 1.00000 0.00000
+ 1.256637061 1.00000 0.00000
+ 1.570796327 0.30000 0.00000
+ 1.884955592 1.00000 0.00000
+ 2.199114858 1.00000 0.00000
+ 2.513274123 1.00000 0.00000
+ 2.827433388 1.00000 0.00000
+ 3.141592654 1.00000 0.00000
diff --git a/regtest/basic/rt-ttmetad2/grid-nonperiodic-threshhalf b/regtest/basic/rt-ttmetad2/grid-nonperiodic-threshhalf
new file mode 100644
index 0000000000000000000000000000000000000000..cee648ecba5e8ac4d9cfc228fa74f40b8d2b0d9b
--- /dev/null
+++ b/regtest/basic/rt-ttmetad2/grid-nonperiodic-threshhalf
@@ -0,0 +1,16 @@
+#! FIELDS psi metadnp1threshhalf.bias der_psi
+#! SET min_psi 0
+#! SET max_psi pi
+#! SET nbins_psi 11
+#! SET periodic_psi false
+ 0.000000000 1.00000 0.00000
+ 0.314159265 0.50000 0.00000
+ 0.628318531 1.00000 0.00000
+ 0.942477796 1.00000 0.00000
+ 1.256637061 1.00000 0.00000
+ 1.570796327 0.30000 0.00000
+ 1.884955592 1.00000 0.00000
+ 2.199114858 1.00000 0.00000
+ 2.513274123 1.00000 0.00000
+ 2.827433388 1.00000 0.00000
+ 3.141592654 1.00000 0.00000
diff --git a/regtest/basic/rt-ttmetad2/plumed.dat b/regtest/basic/rt-ttmetad2/plumed.dat
new file mode 100644
index 0000000000000000000000000000000000000000..d4d5893183ee7a098918f1b8ca25054d823cce44
--- /dev/null
+++ b/regtest/basic/rt-ttmetad2/plumed.dat
@@ -0,0 +1,67 @@
+RESTART
+
+psi: ANGLE ATOMS=7,9,15
+
+METAD ...
+ LABEL=metadnp1
+ ARG=psi
+ SIGMA=0.20
+ HEIGHT=1.20
+ TTBIASFACTOR=2.0
+ TRANSITIONWELL0=1.0
+ TRANSITIONWELL1=2.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS
+ GRID_RFILE=grid-nonperiodic
+ GRID_MIN=0
+ GRID_MAX=pi
+ GRID_BIN=10
+ FMT=%12.5f
+... METAD
+
+METAD ...
+ LABEL=metadnp1thresh
+ ARG=psi
+ SIGMA=0.20
+ HEIGHT=1.20
+ TTBIASFACTOR=2.0
+ TTBIASTHRESHOLD=0.2
+ TRANSITIONWELL0=1.0
+ TRANSITIONWELL1=2.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS-thresh
+ GRID_RFILE=grid-nonperiodic-thresh
+ GRID_MIN=0
+ GRID_MAX=pi
+ GRID_BIN=10
+ FMT=%12.5f
+... METAD
+
+METAD ...
+ LABEL=metadnp1threshhalf
+ ARG=psi
+ SIGMA=0.20
+ HEIGHT=1.20
+ TTBIASFACTOR=2.0
+ TTBIASTHRESHOLD=0.2
+ TTALPHA=0.5
+ TRANSITIONWELL0=1.0
+ TRANSITIONWELL1=2.0
+ TEMP=300.0
+ PACE=500
+ FILE=HILLS-threshhalf
+ GRID_RFILE=grid-nonperiodic-threshhalf
+ GRID_MIN=0
+ GRID_MAX=pi
+ GRID_BIN=10
+ FMT=%12.5f
+... METAD
+
+PRINT ...
+ ARG=psi,metadnp1.bias,metadnp1thresh.bias,metadnp1threshhalf.bias,metadnp1.transbias,metadnp1thresh.transbias,metadnp1threshhalf.transbias
+ STRIDE=500
+ FILE=COLVAR
+ FMT=%8.4f
+... PRINT
diff --git a/regtest/basic/rt-ttmetad2/traj.gro b/regtest/basic/rt-ttmetad2/traj.gro
new file mode 100644
index 0000000000000000000000000000000000000000..c1c387a0144ec8021b9e5b0453be534f2ca906e2
--- /dev/null
+++ b/regtest/basic/rt-ttmetad2/traj.gro
@@ -0,0 +1,525 @@
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 0.00000
+ 22
+ 1ACE HH31 1 1.474 1.585 1.200
+ 1ACE CH3 2 1.483 1.508 1.277
+ 1ACE HH32 3 1.476 1.561 1.372
+ 1ACE HH33 4 1.578 1.455 1.278
+ 1ACE C 5 1.353 1.428 1.279
+ 1ACE O 6 1.263 1.449 1.357
+ 2ALA N 7 1.343 1.328 1.191
+ 2ALA H 8 1.415 1.321 1.120
+ 2ALA CA 9 1.233 1.239 1.159
+ 2ALA HA 10 1.144 1.302 1.155
+ 2ALA CB 11 1.244 1.182 1.013
+ 2ALA HB1 12 1.341 1.136 0.992
+ 2ALA HB2 13 1.159 1.117 0.994
+ 2ALA HB3 14 1.242 1.265 0.942
+ 2ALA C 15 1.207 1.140 1.271
+ 2ALA O 16 1.214 1.017 1.241
+ 3NME N 17 1.191 1.177 1.398
+ 3NME H 18 1.192 1.275 1.421
+ 3NME CH3 19 1.189 1.086 1.518
+ 3NME HH31 20 1.170 0.983 1.487
+ 3NME HH32 21 1.283 1.087 1.574
+ 3NME HH33 22 1.108 1.127 1.578
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 1.00000
+ 22
+ 1ACE HH31 1 1.480 1.571 1.214
+ 1ACE CH3 2 1.481 1.493 1.289
+ 1ACE HH32 3 1.502 1.528 1.390
+ 1ACE HH33 4 1.551 1.417 1.255
+ 1ACE C 5 1.344 1.432 1.275
+ 1ACE O 6 1.250 1.462 1.345
+ 2ALA N 7 1.342 1.327 1.193
+ 2ALA H 8 1.430 1.313 1.144
+ 2ALA CA 9 1.233 1.244 1.166
+ 2ALA HA 10 1.144 1.307 1.173
+ 2ALA CB 11 1.240 1.189 1.017
+ 2ALA HB1 12 1.327 1.124 1.000
+ 2ALA HB2 13 1.150 1.128 1.005
+ 2ALA HB3 14 1.251 1.267 0.941
+ 2ALA C 15 1.221 1.133 1.271
+ 2ALA O 16 1.217 1.015 1.238
+ 3NME N 17 1.204 1.174 1.395
+ 3NME H 18 1.200 1.275 1.398
+ 3NME CH3 19 1.188 1.089 1.516
+ 3NME HH31 20 1.083 1.086 1.543
+ 3NME HH32 21 1.233 0.990 1.511
+ 3NME HH33 22 1.241 1.141 1.596
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 2.00000
+ 22
+ 1ACE HH31 1 1.532 1.520 1.209
+ 1ACE CH3 2 1.478 1.493 1.300
+ 1ACE HH32 3 1.465 1.586 1.356
+ 1ACE HH33 4 1.548 1.426 1.350
+ 1ACE C 5 1.352 1.423 1.279
+ 1ACE O 6 1.252 1.461 1.340
+ 2ALA N 7 1.351 1.326 1.190
+ 2ALA H 8 1.442 1.293 1.160
+ 2ALA CA 9 1.232 1.244 1.160
+ 2ALA HA 10 1.146 1.310 1.151
+ 2ALA CB 11 1.241 1.190 1.016
+ 2ALA HB1 12 1.333 1.132 1.008
+ 2ALA HB2 13 1.160 1.123 0.986
+ 2ALA HB3 14 1.242 1.280 0.955
+ 2ALA C 15 1.203 1.138 1.270
+ 2ALA O 16 1.161 1.021 1.240
+ 3NME N 17 1.230 1.171 1.396
+ 3NME H 18 1.257 1.266 1.417
+ 3NME CH3 19 1.217 1.090 1.512
+ 3NME HH31 20 1.144 1.011 1.493
+ 3NME HH32 21 1.307 1.029 1.526
+ 3NME HH33 22 1.212 1.146 1.605
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 3.00000
+ 22
+ 1ACE HH31 1 1.439 1.582 1.175
+ 1ACE CH3 2 1.474 1.516 1.254
+ 1ACE HH32 3 1.480 1.585 1.338
+ 1ACE HH33 4 1.569 1.465 1.242
+ 1ACE C 5 1.364 1.419 1.280
+ 1ACE O 6 1.277 1.446 1.367
+ 2ALA N 7 1.358 1.323 1.194
+ 2ALA H 8 1.443 1.313 1.140
+ 2ALA CA 9 1.235 1.243 1.164
+ 2ALA HA 10 1.150 1.310 1.170
+ 2ALA CB 11 1.240 1.197 1.019
+ 2ALA HB1 12 1.316 1.119 1.016
+ 2ALA HB2 13 1.145 1.157 0.982
+ 2ALA HB3 14 1.279 1.276 0.955
+ 2ALA C 15 1.201 1.137 1.272
+ 2ALA O 16 1.172 1.021 1.232
+ 3NME N 17 1.218 1.166 1.402
+ 3NME H 18 1.240 1.259 1.434
+ 3NME CH3 19 1.186 1.086 1.518
+ 3NME HH31 20 1.225 0.984 1.527
+ 3NME HH32 21 1.193 1.134 1.616
+ 3NME HH33 22 1.081 1.058 1.509
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 4.00000
+ 22
+ 1ACE HH31 1 1.549 1.508 1.196
+ 1ACE CH3 2 1.500 1.486 1.290
+ 1ACE HH32 3 1.487 1.571 1.357
+ 1ACE HH33 4 1.563 1.415 1.343
+ 1ACE C 5 1.362 1.425 1.270
+ 1ACE O 6 1.265 1.465 1.340
+ 2ALA N 7 1.349 1.324 1.182
+ 2ALA H 8 1.432 1.287 1.138
+ 2ALA CA 9 1.221 1.249 1.168
+ 2ALA HA 10 1.138 1.318 1.184
+ 2ALA CB 11 1.201 1.194 1.025
+ 2ALA HB1 12 1.276 1.117 1.005
+ 2ALA HB2 13 1.096 1.165 1.014
+ 2ALA HB3 14 1.229 1.265 0.947
+ 2ALA C 15 1.217 1.141 1.275
+ 2ALA O 16 1.234 1.024 1.243
+ 3NME N 17 1.183 1.174 1.400
+ 3NME H 18 1.184 1.274 1.412
+ 3NME CH3 19 1.187 1.078 1.509
+ 3NME HH31 20 1.248 0.990 1.490
+ 3NME HH32 21 1.220 1.120 1.604
+ 3NME HH33 22 1.088 1.035 1.527
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 5.00000
+ 22
+ 1ACE HH31 1 1.449 1.585 1.168
+ 1ACE CH3 2 1.479 1.518 1.248
+ 1ACE HH32 3 1.523 1.577 1.328
+ 1ACE HH33 4 1.565 1.461 1.213
+ 1ACE C 5 1.364 1.422 1.284
+ 1ACE O 6 1.305 1.438 1.389
+ 2ALA N 7 1.347 1.326 1.187
+ 2ALA H 8 1.423 1.328 1.122
+ 2ALA CA 9 1.226 1.241 1.162
+ 2ALA HA 10 1.139 1.308 1.162
+ 2ALA CB 11 1.236 1.193 1.023
+ 2ALA HB1 12 1.314 1.117 1.012
+ 2ALA HB2 13 1.137 1.167 0.986
+ 2ALA HB3 14 1.273 1.278 0.966
+ 2ALA C 15 1.195 1.133 1.268
+ 2ALA O 16 1.173 1.016 1.239
+ 3NME N 17 1.204 1.175 1.393
+ 3NME H 18 1.211 1.275 1.403
+ 3NME CH3 19 1.188 1.090 1.513
+ 3NME HH31 20 1.089 1.044 1.509
+ 3NME HH32 21 1.267 1.014 1.509
+ 3NME HH33 22 1.189 1.145 1.607
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 6.00000
+ 22
+ 1ACE HH31 1 1.517 1.511 1.181
+ 1ACE CH3 2 1.490 1.488 1.284
+ 1ACE HH32 3 1.482 1.582 1.339
+ 1ACE HH33 4 1.569 1.421 1.316
+ 1ACE C 5 1.359 1.414 1.282
+ 1ACE O 6 1.272 1.447 1.358
+ 2ALA N 7 1.351 1.320 1.186
+ 2ALA H 8 1.434 1.297 1.133
+ 2ALA CA 9 1.220 1.251 1.159
+ 2ALA HA 10 1.139 1.323 1.167
+ 2ALA CB 11 1.220 1.194 1.018
+ 2ALA HB1 12 1.298 1.120 1.003
+ 2ALA HB2 13 1.120 1.158 0.994
+ 2ALA HB3 14 1.224 1.286 0.960
+ 2ALA C 15 1.201 1.139 1.270
+ 2ALA O 16 1.190 1.022 1.239
+ 3NME N 17 1.203 1.178 1.393
+ 3NME H 18 1.207 1.277 1.409
+ 3NME CH3 19 1.211 1.102 1.515
+ 3NME HH31 20 1.111 1.064 1.534
+ 3NME HH32 21 1.275 1.017 1.492
+ 3NME HH33 22 1.264 1.151 1.597
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 7.00000
+ 22
+ 1ACE HH31 1 1.483 1.590 1.185
+ 1ACE CH3 2 1.505 1.501 1.245
+ 1ACE HH32 3 1.538 1.533 1.344
+ 1ACE HH33 4 1.580 1.430 1.209
+ 1ACE C 5 1.379 1.418 1.267
+ 1ACE O 6 1.298 1.443 1.349
+ 2ALA N 7 1.360 1.320 1.187
+ 2ALA H 8 1.426 1.297 1.114
+ 2ALA CA 9 1.224 1.253 1.180
+ 2ALA HA 10 1.147 1.326 1.205
+ 2ALA CB 11 1.174 1.215 1.037
+ 2ALA HB1 12 1.245 1.152 0.983
+ 2ALA HB2 13 1.084 1.154 1.032
+ 2ALA HB3 14 1.153 1.311 0.992
+ 2ALA C 15 1.212 1.141 1.280
+ 2ALA O 16 1.219 1.022 1.244
+ 3NME N 17 1.191 1.176 1.408
+ 3NME H 18 1.207 1.275 1.423
+ 3NME CH3 19 1.162 1.068 1.509
+ 3NME HH31 20 1.229 0.982 1.503
+ 3NME HH32 21 1.162 1.109 1.610
+ 3NME HH33 22 1.056 1.044 1.499
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 8.00000
+ 22
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+ 1ACE CH3 2 1.523 1.455 1.260
+ 1ACE HH32 3 1.547 1.556 1.294
+ 1ACE HH33 4 1.566 1.393 1.338
+ 1ACE C 5 1.385 1.422 1.255
+ 1ACE O 6 1.308 1.499 1.305
+ 2ALA N 7 1.346 1.311 1.189
+ 2ALA H 8 1.419 1.248 1.159
+ 2ALA CA 9 1.210 1.260 1.193
+ 2ALA HA 10 1.139 1.326 1.242
+ 2ALA CB 11 1.152 1.252 1.051
+ 2ALA HB1 12 1.230 1.210 0.987
+ 2ALA HB2 13 1.066 1.185 1.052
+ 2ALA HB3 14 1.127 1.354 1.024
+ 2ALA C 15 1.206 1.136 1.282
+ 2ALA O 16 1.195 1.023 1.229
+ 3NME N 17 1.210 1.152 1.420
+ 3NME H 18 1.221 1.243 1.463
+ 3NME CH3 19 1.185 1.048 1.518
+ 3NME HH31 20 1.195 0.948 1.475
+ 3NME HH32 21 1.261 1.070 1.593
+ 3NME HH33 22 1.088 1.064 1.565
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 9.00000
+ 22
+ 1ACE HH31 1 1.515 1.474 1.040
+ 1ACE CH3 2 1.535 1.461 1.147
+ 1ACE HH32 3 1.561 1.560 1.184
+ 1ACE HH33 4 1.612 1.386 1.165
+ 1ACE C 5 1.406 1.430 1.217
+ 1ACE O 6 1.361 1.502 1.307
+ 2ALA N 7 1.345 1.316 1.190
+ 2ALA H 8 1.384 1.254 1.121
+ 2ALA CA 9 1.217 1.277 1.242
+ 2ALA HA 10 1.187 1.348 1.319
+ 2ALA CB 11 1.111 1.278 1.134
+ 2ALA HB1 12 1.129 1.198 1.062
+ 2ALA HB2 13 1.018 1.269 1.189
+ 2ALA HB3 14 1.121 1.372 1.079
+ 2ALA C 15 1.217 1.133 1.309
+ 2ALA O 16 1.293 1.044 1.265
+ 3NME N 17 1.132 1.116 1.408
+ 3NME H 18 1.076 1.195 1.437
+ 3NME CH3 19 1.112 1.003 1.490
+ 3NME HH31 20 1.156 0.910 1.456
+ 3NME HH32 21 1.153 1.026 1.588
+ 3NME HH33 22 1.005 0.985 1.500
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 10.00000
+ 22
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+ 1ACE HH32 3 1.528 1.557 1.289
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+ 1ACE C 5 1.385 1.401 1.261
+ 1ACE O 6 1.341 1.416 1.373
+ 2ALA N 7 1.322 1.332 1.167
+ 2ALA H 8 1.364 1.316 1.076
+ 2ALA CA 9 1.190 1.273 1.177
+ 2ALA HA 10 1.125 1.352 1.216
+ 2ALA CB 11 1.134 1.230 1.038
+ 2ALA HB1 12 1.167 1.128 1.016
+ 2ALA HB2 13 1.026 1.238 1.046
+ 2ALA HB3 14 1.174 1.287 0.953
+ 2ALA C 15 1.183 1.157 1.283
+ 2ALA O 16 1.111 1.061 1.259
+ 3NME N 17 1.264 1.157 1.396
+ 3NME H 18 1.320 1.241 1.405
+ 3NME CH3 19 1.264 1.070 1.510
+ 3NME HH31 20 1.163 1.057 1.548
+ 3NME HH32 21 1.311 0.974 1.487
+ 3NME HH33 22 1.326 1.109 1.592
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 11.00000
+ 22
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+ 1ACE CH3 2 1.535 1.442 1.176
+ 1ACE HH32 3 1.521 1.470 1.072
+ 1ACE HH33 4 1.569 1.533 1.224
+ 1ACE C 5 1.402 1.412 1.242
+ 1ACE O 6 1.368 1.454 1.350
+ 2ALA N 7 1.319 1.332 1.177
+ 2ALA H 8 1.363 1.279 1.103
+ 2ALA CA 9 1.194 1.289 1.231
+ 2ALA HA 10 1.153 1.355 1.308
+ 2ALA CB 11 1.092 1.300 1.113
+ 2ALA HB1 12 1.137 1.243 1.032
+ 2ALA HB2 13 1.001 1.243 1.131
+ 2ALA HB3 14 1.070 1.405 1.095
+ 2ALA C 15 1.198 1.143 1.290
+ 2ALA O 16 1.237 1.057 1.213
+ 3NME N 17 1.171 1.126 1.422
+ 3NME H 18 1.164 1.213 1.472
+ 3NME CH3 19 1.200 1.009 1.496
+ 3NME HH31 20 1.118 0.938 1.493
+ 3NME HH32 21 1.284 0.953 1.454
+ 3NME HH33 22 1.230 1.031 1.598
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 12.00000
+ 22
+ 1ACE HH31 1 1.491 1.569 1.138
+ 1ACE CH3 2 1.511 1.462 1.134
+ 1ACE HH32 3 1.614 1.449 1.166
+ 1ACE HH33 4 1.495 1.444 1.028
+ 1ACE C 5 1.416 1.394 1.229
+ 1ACE O 6 1.445 1.392 1.345
+ 2ALA N 7 1.299 1.357 1.181
+ 2ALA H 8 1.278 1.358 1.082
+ 2ALA CA 9 1.196 1.301 1.267
+ 2ALA HA 10 1.185 1.364 1.355
+ 2ALA CB 11 1.063 1.319 1.182
+ 2ALA HB1 12 1.057 1.248 1.100
+ 2ALA HB2 13 0.976 1.288 1.240
+ 2ALA HB3 14 1.037 1.423 1.161
+ 2ALA C 15 1.226 1.161 1.304
+ 2ALA O 16 1.317 1.094 1.258
+ 3NME N 17 1.135 1.110 1.387
+ 3NME H 18 1.064 1.174 1.419
+ 3NME CH3 19 1.121 0.972 1.429
+ 3NME HH31 20 1.163 0.900 1.358
+ 3NME HH32 21 1.177 0.954 1.520
+ 3NME HH33 22 1.016 0.942 1.428
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 13.00000
+ 22
+ 1ACE HH31 1 1.528 1.537 1.077
+ 1ACE CH3 2 1.543 1.448 1.137
+ 1ACE HH32 3 1.634 1.463 1.195
+ 1ACE HH33 4 1.560 1.362 1.072
+ 1ACE C 5 1.421 1.428 1.229
+ 1ACE O 6 1.396 1.520 1.301
+ 2ALA N 7 1.355 1.314 1.219
+ 2ALA H 8 1.385 1.241 1.156
+ 2ALA CA 9 1.249 1.276 1.311
+ 2ALA HA 10 1.297 1.288 1.409
+ 2ALA CB 11 1.122 1.359 1.284
+ 2ALA HB1 12 1.072 1.325 1.193
+ 2ALA HB2 13 1.053 1.352 1.367
+ 2ALA HB3 14 1.153 1.463 1.275
+ 2ALA C 15 1.204 1.131 1.290
+ 2ALA O 16 1.225 1.070 1.185
+ 3NME N 17 1.131 1.077 1.382
+ 3NME H 18 1.104 1.132 1.463
+ 3NME CH3 19 1.083 0.939 1.380
+ 3NME HH31 20 1.012 0.925 1.298
+ 3NME HH32 21 1.168 0.871 1.372
+ 3NME HH33 22 1.036 0.915 1.475
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 14.00000
+ 22
+ 1ACE HH31 1 1.543 1.468 1.123
+ 1ACE CH3 2 1.548 1.443 1.229
+ 1ACE HH32 3 1.566 1.540 1.276
+ 1ACE HH33 4 1.634 1.382 1.257
+ 1ACE C 5 1.420 1.385 1.285
+ 1ACE O 6 1.412 1.375 1.404
+ 2ALA N 7 1.324 1.361 1.200
+ 2ALA H 8 1.345 1.354 1.101
+ 2ALA CA 9 1.189 1.323 1.244
+ 2ALA HA 10 1.163 1.394 1.323
+ 2ALA CB 11 1.094 1.344 1.125
+ 2ALA HB1 12 1.098 1.270 1.045
+ 2ALA HB2 13 0.995 1.352 1.170
+ 2ALA HB3 14 1.120 1.440 1.079
+ 2ALA C 15 1.166 1.169 1.284
+ 2ALA O 16 1.055 1.145 1.330
+ 3NME N 17 1.263 1.077 1.279
+ 3NME H 18 1.356 1.102 1.247
+ 3NME CH3 19 1.246 0.942 1.335
+ 3NME HH31 20 1.142 0.911 1.345
+ 3NME HH32 21 1.293 0.868 1.270
+ 3NME HH33 22 1.292 0.934 1.434
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 15.00000
+ 22
+ 1ACE HH31 1 1.508 1.417 1.043
+ 1ACE CH3 2 1.539 1.448 1.143
+ 1ACE HH32 3 1.565 1.553 1.146
+ 1ACE HH33 4 1.630 1.395 1.169
+ 1ACE C 5 1.438 1.410 1.253
+ 1ACE O 6 1.429 1.471 1.356
+ 2ALA N 7 1.348 1.327 1.217
+ 2ALA H 8 1.362 1.285 1.126
+ 2ALA CA 9 1.233 1.289 1.298
+ 2ALA HA 10 1.269 1.295 1.401
+ 2ALA CB 11 1.107 1.379 1.286
+ 2ALA HB1 12 1.057 1.360 1.191
+ 2ALA HB2 13 1.034 1.369 1.366
+ 2ALA HB3 14 1.141 1.482 1.282
+ 2ALA C 15 1.192 1.141 1.266
+ 2ALA O 16 1.220 1.089 1.156
+ 3NME N 17 1.131 1.075 1.364
+ 3NME H 18 1.117 1.126 1.450
+ 3NME CH3 19 1.090 0.931 1.376
+ 3NME HH31 20 1.156 0.880 1.446
+ 3NME HH32 21 0.996 0.929 1.431
+ 3NME HH33 22 1.090 0.874 1.283
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 16.00000
+ 22
+ 1ACE HH31 1 1.587 1.386 1.166
+ 1ACE CH3 2 1.554 1.425 1.262
+ 1ACE HH32 3 1.559 1.534 1.266
+ 1ACE HH33 4 1.627 1.390 1.335
+ 1ACE C 5 1.417 1.372 1.300
+ 1ACE O 6 1.390 1.364 1.421
+ 2ALA N 7 1.334 1.344 1.205
+ 2ALA H 8 1.365 1.367 1.111
+ 2ALA CA 9 1.190 1.324 1.235
+ 2ALA HA 10 1.160 1.386 1.319
+ 2ALA CB 11 1.105 1.363 1.112
+ 2ALA HB1 12 1.129 1.297 1.029
+ 2ALA HB2 13 0.999 1.351 1.131
+ 2ALA HB3 14 1.125 1.467 1.088
+ 2ALA C 15 1.162 1.180 1.282
+ 2ALA O 16 1.054 1.128 1.258
+ 3NME N 17 1.261 1.106 1.318
+ 3NME H 18 1.349 1.152 1.336
+ 3NME CH3 19 1.250 0.960 1.324
+ 3NME HH31 20 1.264 0.908 1.229
+ 3NME HH32 21 1.322 0.926 1.399
+ 3NME HH33 22 1.153 0.923 1.357
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 17.00000
+ 22
+ 1ACE HH31 1 1.614 1.382 1.173
+ 1ACE CH3 2 1.559 1.432 1.253
+ 1ACE HH32 3 1.547 1.532 1.213
+ 1ACE HH33 4 1.625 1.444 1.339
+ 1ACE C 5 1.426 1.380 1.288
+ 1ACE O 6 1.411 1.348 1.406
+ 2ALA N 7 1.325 1.370 1.200
+ 2ALA H 8 1.341 1.388 1.102
+ 2ALA CA 9 1.189 1.318 1.239
+ 2ALA HA 10 1.170 1.358 1.338
+ 2ALA CB 11 1.084 1.388 1.158
+ 2ALA HB1 12 1.113 1.369 1.055
+ 2ALA HB2 13 0.994 1.336 1.189
+ 2ALA HB3 14 1.075 1.493 1.186
+ 2ALA C 15 1.170 1.163 1.252
+ 2ALA O 16 1.097 1.103 1.171
+ 3NME N 17 1.235 1.099 1.349
+ 3NME H 18 1.305 1.153 1.399
+ 3NME CH3 19 1.220 0.964 1.393
+ 3NME HH31 20 1.315 0.912 1.406
+ 3NME HH32 21 1.168 0.953 1.489
+ 3NME HH33 22 1.178 0.897 1.318
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 18.00000
+ 22
+ 1ACE HH31 1 1.555 1.419 1.126
+ 1ACE CH3 2 1.554 1.431 1.235
+ 1ACE HH32 3 1.554 1.535 1.267
+ 1ACE HH33 4 1.638 1.381 1.283
+ 1ACE C 5 1.423 1.378 1.292
+ 1ACE O 6 1.416 1.347 1.409
+ 2ALA N 7 1.322 1.351 1.211
+ 2ALA H 8 1.350 1.370 1.115
+ 2ALA CA 9 1.185 1.318 1.251
+ 2ALA HA 10 1.171 1.358 1.352
+ 2ALA CB 11 1.091 1.400 1.149
+ 2ALA HB1 12 1.059 1.346 1.060
+ 2ALA HB2 13 1.008 1.443 1.205
+ 2ALA HB3 14 1.154 1.480 1.109
+ 2ALA C 15 1.163 1.166 1.255
+ 2ALA O 16 1.060 1.108 1.214
+ 3NME N 17 1.255 1.102 1.328
+ 3NME H 18 1.335 1.159 1.354
+ 3NME CH3 19 1.246 0.964 1.369
+ 3NME HH31 20 1.154 0.913 1.344
+ 3NME HH32 21 1.323 0.899 1.327
+ 3NME HH33 22 1.251 0.953 1.477
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 19.00000
+ 22
+ 1ACE HH31 1 1.559 1.326 1.133
+ 1ACE CH3 2 1.552 1.413 1.200
+ 1ACE HH32 3 1.538 1.504 1.142
+ 1ACE HH33 4 1.631 1.428 1.273
+ 1ACE C 5 1.426 1.375 1.280
+ 1ACE O 6 1.428 1.345 1.398
+ 2ALA N 7 1.319 1.363 1.209
+ 2ALA H 8 1.322 1.382 1.110
+ 2ALA CA 9 1.191 1.329 1.265
+ 2ALA HA 10 1.186 1.364 1.368
+ 2ALA CB 11 1.075 1.391 1.178
+ 2ALA HB1 12 1.098 1.383 1.072
+ 2ALA HB2 13 0.980 1.348 1.211
+ 2ALA HB3 14 1.066 1.499 1.192
+ 2ALA C 15 1.169 1.174 1.275
+ 2ALA O 16 1.086 1.118 1.203
+ 3NME N 17 1.233 1.105 1.363
+ 3NME H 18 1.312 1.150 1.405
+ 3NME CH3 19 1.242 0.956 1.350
+ 3NME HH31 20 1.219 0.899 1.440
+ 3NME HH32 21 1.165 0.918 1.284
+ 3NME HH33 22 1.333 0.921 1.301
+ 10.00000 10.00000 10.00000
+Generated by trjconv : Gromacs Runs One Microsecond At Cannonball Speeds t= 20.00000
+ 22
+ 1ACE HH31 1 1.622 1.459 1.287
+ 1ACE CH3 2 1.546 1.434 1.214
+ 1ACE HH32 3 1.578 1.365 1.135
+ 1ACE HH33 4 1.509 1.531 1.180
+ 1ACE C 5 1.430 1.358 1.283
+ 1ACE O 6 1.444 1.310 1.394
+ 2ALA N 7 1.315 1.370 1.215
+ 2ALA H 8 1.323 1.427 1.132
+ 2ALA CA 9 1.178 1.334 1.258
+ 2ALA HA 10 1.163 1.376 1.357
+ 2ALA CB 11 1.079 1.393 1.158
+ 2ALA HB1 12 1.096 1.348 1.060
+ 2ALA HB2 13 0.979 1.367 1.192
+ 2ALA HB3 14 1.087 1.501 1.165
+ 2ALA C 15 1.163 1.177 1.270
+ 2ALA O 16 1.073 1.114 1.216
+ 3NME N 17 1.249 1.110 1.347
+ 3NME H 18 1.324 1.165 1.388
+ 3NME CH3 19 1.242 0.964 1.360
+ 3NME HH31 20 1.325 0.920 1.416
+ 3NME HH32 21 1.151 0.938 1.414
+ 3NME HH33 22 1.221 0.913 1.266
+ 10.00000 10.00000 10.00000
diff --git a/src/bias/MetaD.cpp b/src/bias/MetaD.cpp
index cf07c0464abddd9bb7b288e85465b0458780d5df..bbb4be3319d5f95173c52266608e58b01db431f7 100644
--- a/src/bias/MetaD.cpp
+++ b/src/bias/MetaD.cpp
@@ -346,6 +346,17 @@ private:
for(unsigned i=0; i<invsigma.size(); ++i) abs(invsigma[i])>1.e-20?invsigma[i]=1.0/invsigma[i]:0.;
}
};
+ struct TemperingSpecs {
+ bool is_active;
+ std::string name_stem;
+ std::string name;
+ double biasf;
+ double threshold;
+ double alpha;
+ inline TemperingSpecs(bool is_active, const std::string &name_stem, const std::string &name, double biasf, double threshold, double alpha) :
+ is_active(is_active), name_stem(name_stem), name(name), biasf(biasf), threshold(threshold), alpha(alpha)
+ {}
+ };
vector<double> sigma0_;
vector<double> sigma0min_;
vector<double> sigma0max_;
@@ -358,7 +369,10 @@ private:
bool grid_;
double height0_;
double biasf_;
+ static const size_t n_tempering_options_ = 1;
+ static const string tempering_names_[1][2];
double dampfactor_;
+ struct TemperingSpecs tt_specs_;
std::string targetfilename_;
Grid* TargetGrid_;
double kbt_;
@@ -377,6 +391,11 @@ private:
bool acceleration;
double acc;
double acc_restart_mean_;
+ bool calc_max_bias_;
+ double max_bias_;
+ bool calc_transition_bias_;
+ double transition_bias_;
+ vector<vector<double> > transitionwells_;
vector<IFile*> ifiles;
vector<string> ifilesnames;
double uppI_;
@@ -389,17 +408,22 @@ private:
double work_;
long int last_step_warn_grid;
+ static void registerTemperingKeywords(const std::string &name_stem, const std::string &name, Keywords &keys);
+ void readTemperingSpecs(TemperingSpecs &t_specs);
+ void logTemperingSpecs(const TemperingSpecs &t_specs);
void readGaussians(IFile*);
bool readChunkOfGaussians(IFile *ifile, unsigned n);
void writeGaussian(const Gaussian&,OFile&);
void addGaussian(const Gaussian&);
double getHeight(const vector<double>&);
+ void temperHeight(double &height, const TemperingSpecs &t_specs, const double tempering_bias);
double getBiasAndDerivatives(const vector<double>&,double* der=NULL);
double evaluateGaussian(const vector<double>&, const Gaussian&,double* der=NULL);
double getGaussianNormalization( const Gaussian& );
vector<unsigned> getGaussianSupport(const Gaussian&);
bool scanOneHill(IFile *ifile, vector<Value> &v, vector<double> ¢er, vector<double> &sigma, double &height, bool &multivariate);
void computeReweightingFactor();
+ double getTransitionBarrierBias();
string fmt;
public:
@@ -420,6 +444,8 @@ void MetaD::registerKeywords(Keywords& keys) {
keys.addOutputComponent("rct","REWEIGHTING_NGRID","the reweighting factor \\f$c(t)\\f$.");
keys.addOutputComponent("work","default","accumulator for work");
keys.addOutputComponent("acc","ACCELERATION","the metadynamics acceleration factor");
+ keys.addOutputComponent("maxbias", "CALC_MAX_BIAS", "the maximum of the metadynamics V(s, t)");
+ keys.addOutputComponent("transbias", "CALC_TRANSITION_BIAS", "the metadynamics transition bias V*(t)");
keys.use("ARG");
keys.add("compulsory","SIGMA","the widths of the Gaussian hills");
keys.add("compulsory","PACE","the frequency for hill addition");
@@ -429,6 +455,9 @@ void MetaD::registerKeywords(Keywords& keys) {
keys.add("optional","BIASFACTOR","use well tempered metadynamics and use this biasfactor. Please note you must also specify temp");
keys.add("optional","RECT","list of bias factors for all the replicas");
keys.add("optional","DAMPFACTOR","damp hills with exp(-max(V)/(kbT*DAMPFACTOR)");
+ for (size_t i = 0; i < n_tempering_options_; i++) {
+ registerTemperingKeywords(tempering_names_[i][0], tempering_names_[i][1], keys);
+ }
keys.add("optional","TARGET","target to a predefined distribution");
keys.add("optional","TEMP","the system temperature - this is only needed if you are doing well-tempered metadynamics");
keys.add("optional","TAU","in well tempered metadynamics, sets height to (kb*DeltaT*pace*timestep)/tau");
@@ -459,11 +488,22 @@ void MetaD::registerKeywords(Keywords& keys) {
keys.addFlag("WALKERS_MPI",false,"Switch on MPI version of multiple walkers - not compatible with WALKERS_* options other than WALKERS_DIR");
keys.addFlag("ACCELERATION",false,"Set to TRUE if you want to compute the metadynamics acceleration factor.");
keys.add("optional","ACCELERATION_RFILE","a data file from which the acceleration should be read at the initial step of the simulation");
+ keys.addFlag("CALC_MAX_BIAS", false, "Set to TRUE if you want to compute the maximum of the metadynamics V(s, t)");
+ keys.addFlag("CALC_TRANSITION_BIAS", false, "Set to TRUE if you want to compute a metadynamics transition bias V*(t)");
+ keys.add("numbered", "TRANSITIONWELL", "This keyword appears multiple times as TRANSITIONWELLx with x=0,1,2,...,n. Each specifies the coordinates for one well as in transition-tempered metadynamics. At least one must be provided.");
keys.use("RESTART");
keys.use("UPDATE_FROM");
keys.use("UPDATE_UNTIL");
}
+const std::string MetaD::tempering_names_[1][2] = {{"TT", "transition tempered"}};
+
+void MetaD::registerTemperingKeywords(const std::string &name_stem, const std::string &name, Keywords &keys) {
+ keys.add("optional", name_stem + "BIASFACTOR", "use " + name + " metadynamics with this biasfactor. Please note you must also specify temp");
+ keys.add("optional", name_stem + "BIASTHRESHOLD", "use " + name + " metadynamics with this bias threshold. Please note you must also specify " + name_stem + "BIASFACTOR");
+ keys.add("optional", name_stem + "ALPHA", "use " + name + " metadynamics with this hill size decay exponent parameter. Please note you must also specify " + name_stem + "BIASFACTOR");
+}
+
MetaD::~MetaD() {
if(flexbin) delete flexbin;
if(BiasGrid_) delete BiasGrid_;
@@ -483,7 +523,9 @@ MetaD::MetaD(const ActionOptions& ao):
// Grid stuff initialization
BiasGrid_(NULL), wgridstride_(0), grid_(false),
// Metadynamics basic parameters
- height0_(std::numeric_limits<double>::max()), biasf_(-1.0), dampfactor_(0.0), TargetGrid_(NULL),
+ height0_(std::numeric_limits<double>::max()), biasf_(-1.0), dampfactor_(0.0),
+ tt_specs_(false, "TT", "Transition Tempered", -1.0, 0.0, 1.0),
+ TargetGrid_(NULL),
kbt_(0.0),
stride_(0), welltemp_(false),
// Other stuff
@@ -493,6 +535,8 @@ MetaD::MetaD(const ActionOptions& ao):
mw_n_(1), mw_dir_(""), mw_id_(0), mw_rstride_(1),
walkers_mpi(false), mpi_nw_(0), mpi_mw_(0),
acceleration(false), acc(0.0), acc_restart_mean_(0.0),
+ calc_max_bias_(false), max_bias_(0.0),
+ calc_transition_bias_(false), transition_bias_(0.0),
// Interval initialization
uppI_(-1), lowI_(-1), doInt_(false),
isFirstStep(true),
@@ -560,6 +604,13 @@ MetaD::MetaD(const ActionOptions& ao):
if(stride_<=0 ) error("frequency for hill addition is nonsensical");
string hillsfname="HILLS";
parse("FILE",hillsfname);
+
+ // Manually set to calculate special bias quantities
+ // throughout the course of simulation. (These are chosen due to
+ // relevance for tempering and event-driven logic as well.)
+ parseFlag("CALC_MAX_BIAS", calc_max_bias_);
+ parseFlag("CALC_TRANSITION_BIAS", calc_transition_bias_);
+
std::vector<double> rect_biasf_;
parseVector("RECT",rect_biasf_);
if(rect_biasf_.size()>0) {
@@ -584,6 +635,25 @@ MetaD::MetaD(const ActionOptions& ao):
if(dampfactor_>0.0) {
if(kbt_==0.0) error("Unless the MD engine passes the temperature to plumed, with damped metad you must specify it using TEMP");
}
+
+ // Set transition tempering parameters.
+ // Transition wells are read later via calc_transition_bias_.
+ readTemperingSpecs(tt_specs_);
+ if (tt_specs_.is_active) calc_transition_bias_ = true;
+
+ // If any previous option specified to calculate a transition bias,
+ // now read the transition wells for that quantity.
+ if (calc_transition_bias_) {
+ vector<double> tempcoords(getNumberOfArguments());
+ for (unsigned i = 0; ; i++) {
+ if (!parseNumberedVector("TRANSITIONWELL", i, tempcoords) ) break;
+ if (tempcoords.size() != getNumberOfArguments()) {
+ error("incorrect number of coordinates for transition tempering well");
+ }
+ transitionwells_.push_back(tempcoords);
+ }
+ }
+
parse("TARGET",targetfilename_);
if(targetfilename_.length()>0 && kbt_==0.0) error("with TARGET temperature must be specified");
double tau=0.0;
@@ -732,6 +802,62 @@ MetaD::MetaD(const ActionOptions& ao):
log.printf(" Hills relaxation time (tau) %f\n",tau);
log.printf(" KbT %f\n",kbt_);
}
+ // Transition tempered metadynamics options
+ if (tt_specs_.is_active) {
+ logTemperingSpecs(tt_specs_);
+ // Check that the appropriate transition bias quantity is calculated.
+ // (Should never trip, given that the flag is automatically set.)
+ if (!calc_transition_bias_) {
+ error(" transition tempering requires calculation of a transition bias");
+ }
+ }
+
+ // Overall tempering sanity check (this gets tricky when multiple are active).
+ // When multiple temperings are active, it's fine to have one tempering attempt
+ // to increase hill size with increasing bias, so long as the others can shrink
+ // the hills faster than it increases their size in the long-time limit.
+ // This set of checks ensures that the hill sizes eventually decay to zero as c(t)
+ // diverges to infinity.
+ // The alpha parameter allows hills to decay as 1/t^alpha instead of 1/t,
+ // a slower decay, so as t -> infinity, only the temperings with the largest
+ // alphas govern the final asymptotic decay. (Alpha helps prevent false convergence.)
+ if (welltemp_ || dampfactor_ > 0.0 || tt_specs_.is_active) {
+ // Determine the number of active temperings.
+ int n_active = 0;
+ if (welltemp_) n_active++;
+ if (dampfactor_ > 0.0) n_active++;
+ if (tt_specs_.is_active) n_active++;
+ // Find the greatest alpha.
+ double greatest_alpha = 0.0;
+ if (welltemp_) greatest_alpha = max(greatest_alpha, 1.0);
+ if (dampfactor_ > 0.0) greatest_alpha = max(greatest_alpha, 1.0);
+ if (tt_specs_.is_active) greatest_alpha = max(greatest_alpha, tt_specs_.alpha);
+ // Find the least alpha.
+ double least_alpha = 1.0;
+ if (welltemp_) least_alpha = min(least_alpha, 1.0);
+ if (dampfactor_ > 0.0) least_alpha = min(least_alpha, 1.0);
+ if (tt_specs_.is_active) least_alpha = min(least_alpha, tt_specs_.alpha);
+ // Find the inverse harmonic average of the delta T parameters for all
+ // of the temperings with the greatest alpha values.
+ double total_governing_deltaT_inv = 0.0;
+ if (welltemp_ && 1.0 == greatest_alpha && biasf_ != 1.0) total_governing_deltaT_inv += 1.0 / (biasf_ - 1.0);
+ if (dampfactor_ > 0.0 && 1.0 == greatest_alpha) total_governing_deltaT_inv += 1.0 / (dampfactor_);
+ if (tt_specs_.is_active && tt_specs_.alpha == greatest_alpha) total_governing_deltaT_inv += 1.0 / (tt_specs_.biasf - 1.0);
+ // Give a newbie-friendly error message for people using one tempering if
+ // only one is active.
+ if (n_active == 1 && total_governing_deltaT_inv < 0.0) {
+ error("for stable tempering, the bias factor must be greater than one");
+ // Give a slightly more complex error message to users stacking multiple
+ // tempering options at a time, but all with uniform alpha values.
+ } else if (total_governing_deltaT_inv < 0.0 && greatest_alpha == least_alpha) {
+ error("for stable tempering, the sum of the inverse Delta T parameters must be greater than zero!");
+ // Give the most technical error message to users stacking multiple tempering
+ // options with different alpha parameters.
+ } else if (total_governing_deltaT_inv < 0.0 && greatest_alpha != least_alpha) {
+ error("for stable tempering, the sum of the inverse Delta T parameters for the greatest asymptotic hill decay exponents must be greater than zero!");
+ }
+ }
+
if(doInt_) log.printf(" Upper and Lower limits boundaries for the bias are activated at %f - %f\n", lowI_, uppI_);
if(grid_) {
log.printf(" Grid min");
@@ -817,6 +943,36 @@ MetaD::MetaD(const ActionOptions& ao):
getPntrToComponent("acc")->set(acc_rmean);
}
}
+ if (calc_max_bias_) {
+ if (!grid_) error("Calculating the maximum bias on the fly works only with a grid");
+ log.printf(" calculation on the fly of the maximum bias max(V(s,t)) \n");
+ addComponent("maxbias");
+ componentIsNotPeriodic("maxbias");
+ }
+ if (calc_transition_bias_) {
+ if (!grid_) error("Calculating the transition bias on the fly works only with a grid");
+ log.printf(" calculation on the fly of the transition bias V*(t)\n");
+ addComponent("transbias");
+ componentIsNotPeriodic("transbias");
+ log.printf(" Number of transition wells %d\n", transitionwells_.size());
+ if (transitionwells_.size() == 0) error("Calculating the transition bias on the fly requires definition of at least one transition well");
+ // Check that a grid is in use.
+ if (!grid_) error(" transition barrier finding requires a grid for the bias");
+ // Log the wells and check that they are in the grid.
+ for (unsigned i = 0; i < transitionwells_.size(); i++) {
+ // Log the coordinate.
+ log.printf(" Transition well %d at coordinate ", i);
+ for (unsigned j = 0; j < getNumberOfArguments(); j++) log.printf("%f ", transitionwells_[i][j]);
+ log.printf("\n");
+ // Check that the coordinate is in the grid.
+ for (unsigned j = 0; j < getNumberOfArguments(); j++) {
+ double max, min;
+ Tools::convert(gmin[j], min);
+ Tools::convert(gmax[j], max);
+ if (transitionwells_[i][j] < min || transitionwells_[i][j] > max) error(" transition well is not in grid");
+ }
+ }
+ }
// for performance
dp_ = new double[getNumberOfArguments()];
@@ -955,6 +1111,15 @@ MetaD::MetaD(const ActionOptions& ao):
// Calculate the Tiwary-Parrinello reweighting factor if we are restarting from previous hills
if(getRestart() && rewf_grid_.size()>0 ) computeReweightingFactor();
+ // Calculate all special bias quantities desired if restarting with nonzero bias.
+ if(getRestart() && calc_max_bias_) {
+ max_bias_ = BiasGrid_->getMaxValue();
+ getPntrToComponent("maxbias")->set(max_bias_);
+ }
+ if(getRestart() && calc_transition_bias_) {
+ transition_bias_ = getTransitionBarrierBias();
+ getPntrToComponent("transbias")->set(transition_bias_);
+ }
// open grid file for writing
if(wgridstride_>0) {
@@ -1006,6 +1171,10 @@ MetaD::MetaD(const ActionOptions& ao):
log<<" Bibliography "<<plumed.cite("Laio and Parrinello, PNAS 99, 12562 (2002)");
if(welltemp_) log<<plumed.cite(
"Barducci, Bussi, and Parrinello, Phys. Rev. Lett. 100, 020603 (2008)");
+ if(tt_specs_.is_active) {
+ log << plumed.cite("Dama, Rotskoff, Parrinello, and Voth, J. Chem. Theory Comput. 10, 3626 (2014)");
+ log << plumed.cite("Dama, Parrinello, and Voth, Phys. Rev. Lett. 112, 240602 (2014)");
+ }
if(mw_n_>1||walkers_mpi) log<<plumed.cite(
"Raiteri, Laio, Gervasio, Micheletti, and Parrinello, J. Phys. Chem. B 110, 3533 (2006)");
if(adaptive_!=FlexibleBin::none) log<<plumed.cite(
@@ -1022,12 +1191,41 @@ MetaD::MetaD(const ActionOptions& ao):
"Hosek, Toulcova, Bortolato, and Spiwok, J. Phys. Chem. B 120, 2209 (2016)");
if(targetfilename_.length()>0) {
log<<plumed.cite("White, Dama, and Voth, J. Chem. Theory Comput. 11, 2451 (2015)");
- log<<plumed.cite("Marinelli and Faraldo-GoÌmez, Biophys. J. 108, 2779 (2015)");
+ log<<plumed.cite("Marinelli and Faraldo-Gómez, Biophys. J. 108, 2779 (2015)");
log<<plumed.cite("Gil-Ley, Bottaro, and Bussi, submitted (2016)");
}
log<<"\n";
}
+void MetaD::readTemperingSpecs(TemperingSpecs &t_specs) {
+ // Set global tempering parameters.
+ parse(t_specs.name_stem + "BIASFACTOR", t_specs.biasf);
+ if (t_specs.biasf != -1.0) {
+ if (kbt_ == 0.0) {
+ error("Unless the MD engine passes the temperature to plumed, with tempered metad you must specify it using TEMP");
+ }
+ if (t_specs.biasf == 1.0) {
+ error("A bias factor of 1 corresponds to zero delta T and zero hill size, so it is not allowed.");
+ }
+ t_specs.is_active = true;
+ parse(t_specs.name_stem + "BIASTHRESHOLD", t_specs.threshold);
+ if (t_specs.threshold < 0.0) {
+ error(t_specs.name + " bias threshold is nonsensical");
+ }
+ parse(t_specs.name_stem + "ALPHA", t_specs.alpha);
+ if (t_specs.alpha <= 0.0 || t_specs.alpha > 1.0) {
+ error(t_specs.name + " decay shape parameter alpha is nonsensical");
+ }
+ }
+}
+
+void MetaD::logTemperingSpecs(const TemperingSpecs &t_specs) {
+ log.printf(" %s bias factor %f\n", t_specs.name.c_str(), t_specs.biasf);
+ log.printf(" KbT %f\n", kbt_);
+ if (t_specs.threshold != 0.0) log.printf(" %s bias threshold %f\n", t_specs.name.c_str(), t_specs.threshold);
+ if (t_specs.alpha != 1.0) log.printf(" %s decay shape parameter alpha %f\n", t_specs.name.c_str(), t_specs.alpha);
+}
+
void MetaD::readGaussians(IFile *ifile)
{
unsigned ncv=getNumberOfArguments();
@@ -1355,7 +1553,7 @@ double MetaD::getHeight(const vector<double>& cv)
if(biasf_>1.0) {
height = height0_*exp(-vbias/(kbt_*(biasf_-1.0)));
} else {
-// notice that if gamma=1 we store directly -F
+ // notice that if gamma=1 we store directly -F
height = height0_*exp(-vbias/kbt_);
}
}
@@ -1364,6 +1562,10 @@ double MetaD::getHeight(const vector<double>& cv)
double m=BiasGrid_->getMaxValue();
height*=exp(-m/(kbt_*(dampfactor_)));
}
+ if (tt_specs_.is_active) {
+ double vbarrier = transition_bias_;
+ temperHeight(height, tt_specs_, vbarrier);
+ }
if(TargetGrid_) {
double f=TargetGrid_->getValue(cv)-TargetGrid_->getMaxValue();
height*=exp(f/kbt_);
@@ -1371,6 +1573,14 @@ double MetaD::getHeight(const vector<double>& cv)
return height;
}
+void MetaD::temperHeight(double &height, const TemperingSpecs &t_specs, const double tempering_bias) {
+ if (t_specs.alpha == 1.0) {
+ height *= exp(-max(0.0, tempering_bias - t_specs.threshold) / (kbt_ * (t_specs.biasf - 1.0)));
+ } else {
+ height *= pow(1 + (1 - t_specs.alpha) / t_specs.alpha * max(0.0, tempering_bias - t_specs.threshold) / (kbt_ * (t_specs.biasf - 1.0)), - t_specs.alpha / (1 - t_specs.alpha));
+ }
+}
+
void MetaD::calculate()
{
// this is because presently there is no way to properly pass information
@@ -1536,7 +1746,17 @@ void MetaD::update() {
}
}
}
+ // Recalculate special bias quantities whenever the bias has been changed by the update.
+ bool bias_has_changed = (nowAddAHill || (mw_n_ > 1 && getStep() % mw_rstride_ == 0));
if(getStep()%(stride_*rewf_ustride_)==0 && nowAddAHill && rewf_grid_.size()>0 ) computeReweightingFactor();
+ if (calc_max_bias_ && bias_has_changed) {
+ max_bias_ = BiasGrid_->getMaxValue();
+ getPntrToComponent("maxbias")->set(max_bias_);
+ }
+ if (calc_transition_bias_ && (nowAddAHill || (mw_n_ > 1 && getStep() % mw_rstride_ == 0))) {
+ transition_bias_ = getTransitionBarrierBias();
+ getPntrToComponent("transbias")->set(transition_bias_);
+ }
}
/// takes a pointer to the file and a template string with values v and gives back the next center, sigma and height
@@ -1651,5 +1871,39 @@ void MetaD::computeReweightingFactor()
getPntrToComponent("rct")->set(reweight_factor);
}
+double MetaD::getTransitionBarrierBias() {
+
+ // If there is only one well of interest, return the bias at that well point.
+ if (transitionwells_.size() == 1) {
+ double tb_bias = getBiasAndDerivatives(transitionwells_[0], NULL);
+ return tb_bias;
+
+ // Otherwise, check for the least barrier bias between all pairs of wells.
+ // Note that because the paths can be considered edges between the wells' nodes
+ // to make a graph and the path barriers satisfy certain cycle inequalities, it
+ // is sufficient to look at paths corresponding to a minimal spanning tree of the
+ // overall graph rather than examining every edge in the graph.
+ // For simplicity, I chose the star graph with center well 0 as the spanning tree.
+ // It is most efficient to start the path searches from the wells that are
+ // expected to be sampled last, so transitionwell_[0] should correspond to the
+ // starting well. With this choice the searches will terminate in one step until
+ // transitionwell_[1] is sampled.
+ } else {
+ double least_transition_bias, curr_transition_bias;
+ vector<double> sink = transitionwells_[0];
+ vector<double> source = transitionwells_[1];
+ least_transition_bias = BiasGrid_->findMaximalPathMinimum(source, sink);
+ for (unsigned i = 2; i < transitionwells_.size(); i++) {
+ if (least_transition_bias == 0.0) {
+ break;
+ }
+ source = transitionwells_[i];
+ curr_transition_bias = BiasGrid_->findMaximalPathMinimum(source, sink);
+ least_transition_bias = fmin(curr_transition_bias, least_transition_bias);
+ }
+ return least_transition_bias;
+ }
+}
+
}
}
diff --git a/src/tools/Grid.cpp b/src/tools/Grid.cpp
index 472ae2936d03311d743a4227b8da059c0099e560..0a8ac164ce082510d8a77dd9b71790439d94532e 100644
--- a/src/tools/Grid.cpp
+++ b/src/tools/Grid.cpp
@@ -324,6 +324,28 @@ vector<Grid::index_t> Grid::getSplineNeighbors(const vector<unsigned> & indices)
return neighbors;
}
+vector<Grid::index_t> Grid::getNearestNeighbors(const index_t index) const {
+ vector<index_t> nearest_neighs = vector<index_t>();
+ for (unsigned i = 0; i < dimension_; i++) {
+ vector<unsigned> neighsneeded = vector<unsigned>(dimension_, 0);
+ neighsneeded[i] = 1;
+ vector<index_t> singledim_nearest_neighs = getNeighbors(index, neighsneeded);
+ for (unsigned j = 0; j < singledim_nearest_neighs.size(); j++) {
+ index_t neigh = singledim_nearest_neighs[j];
+ if (neigh != index) {
+ nearest_neighs.push_back(neigh);
+ }
+ }
+ }
+ return nearest_neighs;
+}
+
+vector<Grid::index_t> Grid::getNearestNeighbors(const vector<unsigned> &indices) const {
+ plumed_dbg_assert(indices.size() == dimension_);
+ return getNearestNeighbors(getIndex(indices));
+}
+
+
void Grid::addKernel( const KernelFunctions& kernel ) {
plumed_dbg_assert( kernel.ndim()==dimension_ );
std::vector<unsigned> nneighb=kernel.getSupport( dx_ );
@@ -946,4 +968,153 @@ void Grid::mpiSumValuesAndDerivatives( Communicator& comm ) {
comm.Sum( grid_ ); for(unsigned i=0; i<der_.size(); ++i) comm.Sum( der_[i] );
}
+
+bool indexed_lt(pair<Grid::index_t, double> const &x, pair<Grid::index_t, double> const &y) {
+ return x.second < y.second;
+}
+
+double Grid::findMaximalPathMinimum(const std::vector<double> &source, const std::vector<double> &sink) {
+ plumed_dbg_assert(source.size() == dimension_);
+ plumed_dbg_assert(sink.size() == dimension_);
+ // Start and end indices
+ index_t source_idx = getIndex(source);
+ index_t sink_idx = getIndex(sink);
+ // Path cost
+ double maximal_minimum = 0;
+ // In one dimension, path searching is very easy--either go one way if it's not periodic,
+ // or go both ways if it is periodic. There's no reason to pay the cost of Dijkstra.
+ if (dimension_ == 1) {
+ // Do a search from the grid source to grid sink that does not
+ // cross the grid boundary.
+ double curr_min_bias = getValue(source_idx);
+ // Either search from a high source to a low sink.
+ if (source_idx > sink_idx) {
+ for (index_t i = source_idx; i >= sink_idx; i--) {
+ if (curr_min_bias == 0.0) {
+ break;
+ }
+ curr_min_bias = fmin(curr_min_bias, getValue(i));
+ }
+ // Or search from a low source to a high sink.
+ } else if (source_idx < sink_idx) {
+ for (index_t i = source_idx; i <= sink_idx; i++) {
+ if (curr_min_bias == 0.0) {
+ break;
+ }
+ curr_min_bias = fmin(curr_min_bias, getValue(i));
+ }
+ }
+ maximal_minimum = curr_min_bias;
+ // If the grid is periodic, also do the search that crosses
+ // the grid boundary.
+ if (pbc_[0]) {
+ double curr_min_bias = getValue(source_idx);
+ // Either go from a high source to the upper boundary and
+ // then from the bottom boundary to the sink
+ if (source_idx > sink_idx) {
+ for (index_t i = source_idx; i < maxsize_; i++) {
+ if (curr_min_bias == 0.0) {
+ break;
+ }
+ curr_min_bias = fmin(curr_min_bias, getValue(i));
+ }
+ for (index_t i = 0; i <= sink_idx; i++) {
+ if (curr_min_bias == 0.0) {
+ break;
+ }
+ curr_min_bias = fmin(curr_min_bias, getValue(i));
+ }
+ // Or go from a low source to the bottom boundary and
+ // then from the high boundary to the sink
+ } else if (source_idx < sink_idx) {
+ for (index_t i = source_idx; i > 0; i--) {
+ if (curr_min_bias == 0.0) {
+ break;
+ }
+ curr_min_bias = fmin(curr_min_bias, getValue(i));
+ }
+ curr_min_bias = fmin(curr_min_bias, getValue(0));
+ for (index_t i = maxsize_ - 1; i <= sink_idx; i--) {
+ if (curr_min_bias == 0.0) {
+ break;
+ }
+ curr_min_bias = fmin(curr_min_bias, getValue(i));
+ }
+ }
+ // If the boundary crossing paths was more biased, it's
+ // minimal bias replaces the non-boundary-crossing path's
+ // minimum.
+ maximal_minimum = fmax(maximal_minimum, curr_min_bias);
+ }
+ // The one dimensional path search is complete.
+ return maximal_minimum;
+ // In two or more dimensions, path searching isn't trivial and we really
+ // do need to use a path search algorithm. Dijkstra is the simplest decent
+ // one. Using it we've never found the path search to be performance
+ // limiting in any solvated biomolecule test system, but faster options are
+ // easy to imagine if they become necessary. NB-In this case, we're actually
+ // using a greedy variant of Dijkstra's algorithm where the first possible
+ // path to a point always controls the path cost to that point. The structure
+ // of the cost function in this case guarantees that the calculated costs will
+ // be correct using this variant even though fine details of the paths may not
+ // match a normal Dijkstra search.
+ } else if (dimension_ > 1) {
+ // Prepare calculation temporaries for Dijkstra's algorithm.
+ // Minimal path costs from source to a given grid point
+ vector<double> mins_from_source = vector<double>(maxsize_, -1.0);
+ // Heap for tracking available steps, steps are recorded as std::pairs of
+ // an index and a value.
+ vector< pair<index_t, double> > next_steps;
+ pair<index_t, double> curr_indexed_val;
+ make_heap(next_steps.begin(), next_steps.end(), indexed_lt);
+ // The search begins at the source index.
+ next_steps.push_back(pair<index_t, double>(source_idx, getValue(source_idx)));
+ push_heap(next_steps.begin(), next_steps.end(), indexed_lt);
+ // At first no points have been examined and the optimal path has not been found.
+ index_t n_examined = 0;
+ bool path_not_found = true;
+ // Until a path is found,
+ while (path_not_found) {
+ // Examine the grid point currently most accessible from
+ // the set of all previously explored grid points by popping
+ // it from the top of the heap.
+ pop_heap(next_steps.begin(), next_steps.end(), indexed_lt);
+ curr_indexed_val = next_steps.back();
+ next_steps.pop_back();
+ n_examined++;
+ // Check if this point is the sink point, and if so
+ // finish the loop.
+ if (curr_indexed_val.first == sink_idx) {
+ path_not_found = false;
+ maximal_minimum = curr_indexed_val.second;
+ break;
+ // Check if this point has reached the worst possible
+ // value, and if so stop looking for paths.
+ } else if (curr_indexed_val.second == 0.0) {
+ maximal_minimum = 0.0;
+ break;
+ }
+ // If the search is not over, add this grid point's neighbors to the
+ // possible next points to search for the sink.
+ vector<index_t> neighs = getNearestNeighbors(curr_indexed_val.first);
+ for (unsigned k = 0; k < neighs.size(); k++) {
+ index_t i = neighs[k];
+ // If the neighbor has not already been added to the list of possible next steps,
+ if (mins_from_source[i] == -1.0) {
+ // Set the cost to reach it via a path through the current point being examined.
+ mins_from_source[i] = fmin(curr_indexed_val.second, getValue(i));
+ // Add the neighboring point to the heap of potential next steps.
+ next_steps.push_back(pair<index_t, double>(i, mins_from_source[i]));
+ push_heap(next_steps.begin(), next_steps.end(), indexed_lt);
+ }
+ }
+ // Move on to the next best looking step along any of the paths
+ // growing from the source.
+ }
+ // The multidimensional path search is now complete.
+ return maximal_minimum;
+ }
+ return 0.0;
+}
+
}
diff --git a/src/tools/Grid.h b/src/tools/Grid.h
index 2e6c13415eddc9bbfe67ca2ad30374da1a463ee9..04960bc1359943b38928b4896a5f1b81cb1b3ea8 100644
--- a/src/tools/Grid.h
+++ b/src/tools/Grid.h
@@ -145,6 +145,9 @@ public:
std::vector<index_t> getNeighbors(index_t index,const std::vector<unsigned> & neigh) const;
std::vector<index_t> getNeighbors(const std::vector<unsigned> & indices,const std::vector<unsigned> & neigh) const;
std::vector<index_t> getNeighbors(const std::vector<double> & x,const std::vector<unsigned> & neigh) const;
+/// get nearest neighbors (those separated by exactly one lattice unit)
+ std::vector<index_t> getNearestNeighbors(const index_t index) const;
+ std::vector<index_t> getNearestNeighbors(const std::vector<unsigned> &indices) const;
/// write header for grid file
void writeHeader(OFile& file);
@@ -214,6 +217,9 @@ public:
double integrate( std::vector<unsigned>& npoints );
///
void mpiSumValuesAndDerivatives( Communicator& comm );
+/// Find the maximum over paths of the minimum value of the gridded function along the paths
+/// for all paths of neighboring grid lattice points from a source point to a sink point.
+ virtual double findMaximalPathMinimum(const std::vector<double> &source, const std::vector<double> &sink);
};