Continuous1D functions with periodic option in ForceField

wrappers/python/simtk/openmm/app/forcefield.py

@@ -86,6 +86,8 @@ def _parseFunctions(element):
                 params[key] = int(function.attrib[key])
             elif key.endswith('min') or key.endswith('max'):
                 params[key] = float(function.attrib[key])
+        if functionType == 'Continuous1D':
+            params['periodic'] = bool(eval(function.attrib.get('periodic')))
         functions.append((function.attrib['name'], functionType, values, params))
     return functions
 
@@ -93,7 +95,7 @@ def _createFunctions(force, functions):
     """Add TabulatedFunctions to a Force based on the information that was recorded by _parseFunctions()."""
     for (name, type, values, params) in functions:
         if type == 'Continuous1D':
-            force.addTabulatedFunction(name, mm.Continuous1DFunction(values, params['min'], params['max']))
+            force.addTabulatedFunction(name, mm.Continuous1DFunction(values, params['min'], params['max'], params['periodic']))
         elif type == 'Continuous2D':
             force.addTabulatedFunction(name, mm.Continuous2DFunction(params['xsize'], params['ysize'], values, params['xmin'], params['xmax'], params['ymin'], params['ymax']))
         elif type == 'Continuous3D':
@@ -3166,7 +3168,7 @@ class CustomManyParticleGenerator(object):
             force.setTypeFilter(index, types)
         for (name, type, values, params) in self.functions:
             if type == 'Continuous1D':
-                force.addTabulatedFunction(name, mm.Continuous1DFunction(values, params['min'], params['max']))
+                force.addTabulatedFunction(name, mm.Continuous1DFunction(values, params['min'], params['max'], params['periodic']))
             elif type == 'Continuous2D':
                 force.addTabulatedFunction(name, mm.Continuous2DFunction(params['xsize'], params['ysize'], values, params['xmin'], params['xmax'], params['ymin'], params['ymax']))
             elif type == 'Continuous3D':