Adding call to to the voxel conversion script.

tests/regression_tests/plot/test.py

@@ -1,7 +1,7 @@
 import glob
 import hashlib
 import os
-
+from subprocess import call
 import h5py
 import openmc
 
@@ -52,6 +52,10 @@ class PlotTestHarness(TestHarness):
         sha512.update(outstr)
         outstr = sha512.hexdigest()
 
+        # test the voxel to vtk conversion script
+        call(['../../../scripts/openmc-voxel-to-vtk'] +
+             glob.glob('plot_4.h5'))
+
         return outstr