Raise Warning if the Capacity Array is Not Set But mapc2p is

src/pyclaw/solution.py

@@ -198,8 +198,6 @@ def is_valid(self):
          - (bool) - True if valid, false otherwise
         """
         return all([state.is_valid() for state in self.states])
-
-
     def __str__(self):
         output = "states:\n"
         # This is information about each of the states

src/pyclaw/state.py

@@ -187,6 +187,16 @@ def is_valid(self):
             if not self.aux.flags['F_CONTIGUOUS']:
                 logger.debug('aux array is not Fortran contiguous.')
                 valid = False
+        if self.grid.mapc2p is not None and self.aux is None:
+            raise ValueError("Mapped grid requires capacity array to be set. " \
+            "Please set state.aux.")
+        elif self.grid.mapc2p is not None and self.aux is not None:
+            if self.index_capa == -1:
+                raise ValueError("Capacity function index is not set. " \
+                "Please set state.index_capa to the appropriate index in the aux array.")
+            elif self.index_capa < 0 or self.index_capa > self.num_aux -1:
+                raise ValueError("Capacity function index out of range. " \
+                "Please set state.index_capa to the appropriate index in the aux array.")
         return valid
 
     def set_cparam(self,fortran_module):