diff --git a/regtest/analysis/rt0/Makefile b/regtest/analysis/rt0/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..3703b27cea227aa053fb6d1d73f861e4384dbcee
--- /dev/null
+++ b/regtest/analysis/rt0/Makefile
@@ -0,0 +1 @@
+include ../../scripts/test.make
diff --git a/regtest/analysis/rt0/config b/regtest/analysis/rt0/config
new file mode 100644
index 0000000000000000000000000000000000000000..f93ec1a97465724691bf162d4735f5ea3648bbb4
--- /dev/null
+++ b/regtest/analysis/rt0/config
@@ -0,0 +1,3 @@
+type=driver
+# this is to test a different name
+arg="--plumed plumed.dat --ixyz trajectory.xyz"
diff --git a/regtest/analysis/rt0/histoA.reference b/regtest/analysis/rt0/histoA.reference
new file mode 100644
index 0000000000000000000000000000000000000000..11425019a9f1aa584941f61388daf5301c3fbaac
--- /dev/null
+++ b/regtest/analysis/rt0/histoA.reference
@@ -0,0 +1,106 @@
+#! FIELDS x probs
+#! SET min_x 0.0
+#! SET max_x 3.0
+#! SET nbins_x  101
+#! SET periodic_x false
+   0.0000   0.0000
+   0.0300   0.0000
+   0.0600   0.0000
+   0.0900   0.0000
+   0.1200   0.0000
+   0.1500   0.0000
+   0.1800   0.0000
+   0.2100   0.0000
+   0.2400   0.0000
+   0.2700   0.0000
+   0.3000   0.0000
+   0.3300   0.0000
+   0.3600   0.0000
+   0.3900   0.0000
+   0.4200   0.0000
+   0.4500   0.0000
+   0.4800   0.0000
+   0.5100   0.0000
+   0.5400   0.0000
+   0.5700   0.0000
+   0.6000   0.0000
+   0.6300   0.0000
+   0.6600   0.0000
+   0.6900   0.0000
+   0.7200   0.0000
+   0.7500   0.0000
+   0.7800   0.0000
+   0.8100   0.0000
+   0.8400   0.0000
+   0.8700   0.0000
+   0.9000   0.0000
+   0.9300   0.0000
+   0.9600   0.0000
+   0.9900   0.0000
+   1.0200   0.0000
+   1.0500   0.0000
+   1.0800   0.0000
+   1.1100   0.0000
+   1.1400   0.0031
+   1.1700   0.0086
+   1.2000   0.0221
+   1.2300   0.0521
+   1.2600   0.1119
+   1.2900   0.2199
+   1.3200   0.3947
+   1.3500   0.6476
+   1.3800   0.9709
+   1.4100   1.3304
+   1.4400   1.6661
+   1.4700   1.9069
+   1.5000   1.9947
+   1.5300   1.9069
+   1.5600   1.6661
+   1.5900   1.3304
+   1.6200   0.9724
+   1.6500   0.6520
+   1.6800   0.4067
+   1.7100   0.2497
+   1.7400   0.1799
+   1.7700   0.1937
+   1.8000   0.2921
+   1.8300   0.4788
+   1.8600   0.7517
+   1.8900   1.0893
+   1.9200   1.4485
+   1.9500   1.7603
+   1.9800   1.9552
+   2.0100   1.9848
+   2.0400   1.8414
+   2.0700   1.5613
+   2.1000   1.2099
+   2.1300   0.8568
+   2.1600   0.5546
+   2.1900   0.3281
+   2.2200   0.1774
+   2.2500   0.0876
+   2.2800   0.0396
+   2.3100   0.0163
+   2.3400   0.0062
+   2.3700   0.0000
+   2.4000   0.0000
+   2.4300   0.0000
+   2.4600   0.0000
+   2.4900   0.0000
+   2.5200   0.0000
+   2.5500   0.0000
+   2.5800   0.0000
+   2.6100   0.0000
+   2.6400   0.0000
+   2.6700   0.0000
+   2.7000   0.0000
+   2.7300   0.0000
+   2.7600   0.0000
+   2.7900   0.0000
+   2.8200   0.0000
+   2.8500   0.0000
+   2.8800   0.0000
+   2.9100   0.0000
+   2.9400   0.0000
+   2.9700   0.0000
+   3.0000   0.0000
diff --git a/regtest/analysis/rt0/histoB.reference b/regtest/analysis/rt0/histoB.reference
new file mode 100644
index 0000000000000000000000000000000000000000..11425019a9f1aa584941f61388daf5301c3fbaac
--- /dev/null
+++ b/regtest/analysis/rt0/histoB.reference
@@ -0,0 +1,106 @@
+#! FIELDS x probs
+#! SET min_x 0.0
+#! SET max_x 3.0
+#! SET nbins_x  101
+#! SET periodic_x false
+   0.0000   0.0000
+   0.0300   0.0000
+   0.0600   0.0000
+   0.0900   0.0000
+   0.1200   0.0000
+   0.1500   0.0000
+   0.1800   0.0000
+   0.2100   0.0000
+   0.2400   0.0000
+   0.2700   0.0000
+   0.3000   0.0000
+   0.3300   0.0000
+   0.3600   0.0000
+   0.3900   0.0000
+   0.4200   0.0000
+   0.4500   0.0000
+   0.4800   0.0000
+   0.5100   0.0000
+   0.5400   0.0000
+   0.5700   0.0000
+   0.6000   0.0000
+   0.6300   0.0000
+   0.6600   0.0000
+   0.6900   0.0000
+   0.7200   0.0000
+   0.7500   0.0000
+   0.7800   0.0000
+   0.8100   0.0000
+   0.8400   0.0000
+   0.8700   0.0000
+   0.9000   0.0000
+   0.9300   0.0000
+   0.9600   0.0000
+   0.9900   0.0000
+   1.0200   0.0000
+   1.0500   0.0000
+   1.0800   0.0000
+   1.1100   0.0000
+   1.1400   0.0031
+   1.1700   0.0086
+   1.2000   0.0221
+   1.2300   0.0521
+   1.2600   0.1119
+   1.2900   0.2199
+   1.3200   0.3947
+   1.3500   0.6476
+   1.3800   0.9709
+   1.4100   1.3304
+   1.4400   1.6661
+   1.4700   1.9069
+   1.5000   1.9947
+   1.5300   1.9069
+   1.5600   1.6661
+   1.5900   1.3304
+   1.6200   0.9724
+   1.6500   0.6520
+   1.6800   0.4067
+   1.7100   0.2497
+   1.7400   0.1799
+   1.7700   0.1937
+   1.8000   0.2921
+   1.8300   0.4788
+   1.8600   0.7517
+   1.8900   1.0893
+   1.9200   1.4485
+   1.9500   1.7603
+   1.9800   1.9552
+   2.0100   1.9848
+   2.0400   1.8414
+   2.0700   1.5613
+   2.1000   1.2099
+   2.1300   0.8568
+   2.1600   0.5546
+   2.1900   0.3281
+   2.2200   0.1774
+   2.2500   0.0876
+   2.2800   0.0396
+   2.3100   0.0163
+   2.3400   0.0062
+   2.3700   0.0000
+   2.4000   0.0000
+   2.4300   0.0000
+   2.4600   0.0000
+   2.4900   0.0000
+   2.5200   0.0000
+   2.5500   0.0000
+   2.5800   0.0000
+   2.6100   0.0000
+   2.6400   0.0000
+   2.6700   0.0000
+   2.7000   0.0000
+   2.7300   0.0000
+   2.7600   0.0000
+   2.7900   0.0000
+   2.8200   0.0000
+   2.8500   0.0000
+   2.8800   0.0000
+   2.9100   0.0000
+   2.9400   0.0000
+   2.9700   0.0000
+   3.0000   0.0000
diff --git a/regtest/analysis/rt0/plumed.dat b/regtest/analysis/rt0/plumed.dat
new file mode 100755
index 0000000000000000000000000000000000000000..e7911eceaebf9144adf44cccb3d30c3a4ffa8610
--- /dev/null
+++ b/regtest/analysis/rt0/plumed.dat
@@ -0,0 +1,31 @@
+x: DISTANCE ATOMS=1,2
+
+RESTRAINT ARG=x SLOPE=1.0 AT=0.0
+
+HISTOGRAM ... 
+  ARG=x
+  TEMP=300
+  GRID_MIN=0.0
+  GRID_MAX=3.0
+  GRID_BIN=100
+  BANDWIDTH=0.1
+  GRID_WFILE=histoA
+  FMT=%8.4f
+  RUN=1
+... HISTOGRAM
+
+HISTOGRAM ...
+  ARG=x
+  TEMP=300
+  GRID_MIN=0.0
+  GRID_MAX=3.0
+  GRID_BIN=100
+  BANDWIDTH=0.1
+  GRID_WFILE=histoB
+  FMT=%8.4f
+  REWEIGHT_BIAS
+  RUN=1
+... HISTOGRAM
+
+
+
diff --git a/regtest/analysis/rt0/trajectory.xyz b/regtest/analysis/rt0/trajectory.xyz
new file mode 100644
index 0000000000000000000000000000000000000000..c910ae5c6fda2241cfe5be857f9b8493db430ed3
--- /dev/null
+++ b/regtest/analysis/rt0/trajectory.xyz
@@ -0,0 +1,12 @@
+2
+0 0 0
+X 0 0 0
+X 0 0 1
+2
+0 0 0
+X 0 0 0
+X 0 0 1.5
+2
+0 0 0
+X 0 0 0
+X 0 0 2