diff --git a/SimPEG/Mesh/DiffOperators.py b/SimPEG/Mesh/DiffOperators.py
index 7a965e0f..87b6aac3 100644
--- a/SimPEG/Mesh/DiffOperators.py
+++ b/SimPEG/Mesh/DiffOperators.py
@@ -644,3 +644,7 @@ class DiffOperators(object):
     def getFaceMassDeriv(self):
         Av = self.aveF2CC
         return Av.T * sdiag(self.vol)
+
+    def getEdgeMassDeriv(self):
+        Av = self.aveE2CC
+        return Av.T * sdiag(self.vol)
diff --git a/SimPEG/Mesh/TensorView.py b/SimPEG/Mesh/TensorView.py
index 7446aecd..a664501a 100644
--- a/SimPEG/Mesh/TensorView.py
+++ b/SimPEG/Mesh/TensorView.py
@@ -404,7 +404,7 @@ class TensorView(object):
         ::
 
             def function(var, ax, clim, tlt, i):
-                tlt.set_text('%%d'%%i)
+                tlt.set_text('%d'%i)
                 return mesh.plotImage(var, imageType='CC', ax=ax, clim=clim)
 
             mesh.video([model1, model2, ..., modeln],function)