diff --git a/regtest/basic/rt-torsion/COLVAR.reference b/regtest/basic/rt-torsion/COLVAR.reference
new file mode 100644
index 0000000000000000000000000000000000000000..4a66603290bc1f3792b82f29b4a0c301b9f8d414
--- /dev/null
+++ b/regtest/basic/rt-torsion/COLVAR.reference
@@ -0,0 +1,7 @@
+#! FIELDS time t
+#! SET min_t -pi
+#! SET max_t pi
+ 0.000000 0.000000
+ 1.000000 -1.570796
+ 2.000000 -3.141593
+ 3.000000 1.570796
diff --git a/regtest/basic/rt-torsion/Makefile b/regtest/basic/rt-torsion/Makefile
new file mode 100644
index 0000000000000000000000000000000000000000..3703b27cea227aa053fb6d1d73f861e4384dbcee
--- /dev/null
+++ b/regtest/basic/rt-torsion/Makefile
@@ -0,0 +1 @@
+include ../../scripts/test.make
diff --git a/regtest/basic/rt-torsion/config b/regtest/basic/rt-torsion/config
new file mode 100644
index 0000000000000000000000000000000000000000..726743cdc4164e45eb56e680841ffd6ef405568a
--- /dev/null
+++ b/regtest/basic/rt-torsion/config
@@ -0,0 +1,3 @@
+type=driver
+# this is to test a different name
+arg="--plumed plumed.dat --ixyz traj.xyz"
diff --git a/regtest/basic/rt-torsion/der.reference b/regtest/basic/rt-torsion/der.reference
new file mode 100644
index 0000000000000000000000000000000000000000..e2efe48ff1304407d6f6b4b67d1138bdbf41833f
--- /dev/null
+++ b/regtest/basic/rt-torsion/der.reference
@@ -0,0 +1,109 @@
+#! FIELDS time parameter t
+ 0.000000 0   0.0000
+ 0.000000 1   0.0000
+ 0.000000 2   0.2000
+ 0.000000 3   0.0000
+ 0.000000 4   0.0000
+ 0.000000 5  -0.2000
+ 0.000000 6   0.0000
+ 0.000000 7   0.0000
+ 0.000000 8   0.0000
+ 0.000000 9   0.0000
+ 0.000000 10   0.0000
+ 0.000000 11   0.0000
+ 0.000000 12   0.0000
+ 0.000000 13   0.0000
+ 0.000000 14   0.2000
+ 0.000000 15   0.0000
+ 0.000000 16   0.0000
+ 0.000000 17  -0.2000
+ 0.000000 18   0.0000
+ 0.000000 19   0.0000
+ 0.000000 20   0.0000
+ 0.000000 21   0.0000
+ 0.000000 22   0.0000
+ 0.000000 23   0.0000
+ 0.000000 24   0.0000
+ 0.000000 25   0.0000
+ 0.000000 26   0.0000
+ 1.000000 0   0.0000
+ 1.000000 1   0.0000
+ 1.000000 2   0.2000
+ 1.000000 3   0.0000
+ 1.000000 4   0.0000
+ 1.000000 5  -0.2000
+ 1.000000 6   0.0000
+ 1.000000 7   0.0000
+ 1.000000 8   0.0000
+ 1.000000 9   0.0000
+ 1.000000 10   0.0000
+ 1.000000 11   0.0000
+ 1.000000 12  -0.2000
+ 1.000000 13   0.0000
+ 1.000000 14   0.0000
+ 1.000000 15   0.2000
+ 1.000000 16   0.0000
+ 1.000000 17   0.0000
+ 1.000000 18   0.0000
+ 1.000000 19   0.0000
+ 1.000000 20  -1.0000
+ 1.000000 21   0.0000
+ 1.000000 22   0.0000
+ 1.000000 23   0.0000
+ 1.000000 24  -1.0000
+ 1.000000 25   0.0000
+ 1.000000 26   0.0000
+ 2.000000 0   0.0000
+ 2.000000 1   0.0000
+ 2.000000 2   0.2000
+ 2.000000 3   0.0000
+ 2.000000 4   0.0000
+ 2.000000 5  -0.2000
+ 2.000000 6   0.0000
+ 2.000000 7   0.0000
+ 2.000000 8   0.0000
+ 2.000000 9   0.0000
+ 2.000000 10   0.0000
+ 2.000000 11   0.0000
+ 2.000000 12   0.0000
+ 2.000000 13   0.0000
+ 2.000000 14  -0.2000
+ 2.000000 15   0.0000
+ 2.000000 16   0.0000
+ 2.000000 17   0.2000
+ 2.000000 18   0.0000
+ 2.000000 19   0.0000
+ 2.000000 20   0.0000
+ 2.000000 21   0.0000
+ 2.000000 22   0.0000
+ 2.000000 23   0.0000
+ 2.000000 24   0.0000
+ 2.000000 25   0.0000
+ 2.000000 26   0.0000
+ 3.000000 0   0.0000
+ 3.000000 1   0.0000
+ 3.000000 2   0.2000
+ 3.000000 3   0.0000
+ 3.000000 4   0.0000
+ 3.000000 5  -0.2000
+ 3.000000 6   0.0000
+ 3.000000 7   0.0000
+ 3.000000 8   0.0000
+ 3.000000 9   0.0000
+ 3.000000 10   0.0000
+ 3.000000 11   0.0000
+ 3.000000 12   0.2000
+ 3.000000 13   0.0000
+ 3.000000 14   0.0000
+ 3.000000 15  -0.2000
+ 3.000000 16   0.0000
+ 3.000000 17   0.0000
+ 3.000000 18   0.0000
+ 3.000000 19   0.0000
+ 3.000000 20  -1.0000
+ 3.000000 21   0.0000
+ 3.000000 22   0.0000
+ 3.000000 23   0.0000
+ 3.000000 24  -1.0000
+ 3.000000 25   0.0000
+ 3.000000 26   0.0000
diff --git a/regtest/basic/rt-torsion/plumed.dat b/regtest/basic/rt-torsion/plumed.dat
new file mode 100644
index 0000000000000000000000000000000000000000..1e8e08d12bd7273a5d00deac79f3786d2806c874
--- /dev/null
+++ b/regtest/basic/rt-torsion/plumed.dat
@@ -0,0 +1,7 @@
+t: TORSION ATOMS=1,2,3,4
+
+PRINT ARG=t FILE=COLVAR
+
+DUMPDERIVATIVES ARG=t FILE=der FMT=%8.4f
+
+
diff --git a/regtest/basic/rt-torsion/traj.xyz b/regtest/basic/rt-torsion/traj.xyz
new file mode 100644
index 0000000000000000000000000000000000000000..c0e66cf2b2540970e59504e16dea3ecfecf656ba
--- /dev/null
+++ b/regtest/basic/rt-torsion/traj.xyz
@@ -0,0 +1,24 @@
+4
+100 100 100
+X 5 0 0
+X 0 0 0
+X 0 5 0
+X 5 5 0
+4
+100 100 100
+X 5 0 0
+X 0 0 0
+X 0 5 0
+X 0 5 5
+4
+100 100 100
+X 5 0 0
+X 0 0 0
+X 0 5 0
+X -5 5 0
+4
+100 100 100
+X 5 0 0
+X 0 0 0
+X 0 5 0
+X 0 5 -5