From 90fa9c372794a7c36a85a1bb50a611710819636b Mon Sep 17 00:00:00 2001
From: rowanc1 <rowan@visiblegeology.com>
Date: Mon, 24 Feb 2014 14:38:19 -0800
Subject: [PATCH] Added check on modelPair in Problem.

---
 SimPEG/Problem.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/SimPEG/Problem.py b/SimPEG/Problem.py
index c6f381f5..f93c0c7a 100644
--- a/SimPEG/Problem.py
+++ b/SimPEG/Problem.py
@@ -1,5 +1,5 @@
 import Utils, Data, numpy as np, scipy.sparse as sp
-
+import Model
 
 class BaseProblem(object):
     """
@@ -39,10 +39,12 @@ class BaseProblem(object):
     counter = None   #: A SimPEG.Utils.Counter object
 
     dataPair = Data.BaseData
+    modelPair = Model.BaseModel
 
     def __init__(self, mesh, model, *args, **kwargs):
         Utils.setKwargs(self, **kwargs)
         self.mesh = mesh
+        assert isinstance(d, self.modelPair), "Model object must be an instance of a %s class."%(self.modelPair.__name__)
         self.model = model
 
     @property