diff --git a/examples/example-forcefield.py b/examples/example-forcefield.py
index ce0a607d..60c47452 100644
--- a/examples/example-forcefield.py
+++ b/examples/example-forcefield.py
@@ -22,10 +22,10 @@ def addForce(self, m, out_force, pos, vel):
         with out_force.writeableArray() as wa:
             wa[:] += ( (self.initpos-pos.value) * self.ks.value  )
                  
-    def addDForce(self, df, dx, params):
+    def addDForce(self, params, df, dx):
         pass
         
-    #def addKToMatrix(self, a, b):
+    #def addKToMatrix(self, params, number_of_nodes, number_of_dofs_per_node):
     #    print(" Python::addKToMatrix: ", a, " ", b)