Update directive to None the Wsmooth after iteration.

SimPEG/Directives.py

@@ -303,26 +303,27 @@ class Update_IRLS(InversionDirective):
         # Set the weighting matrix to None so that it is recomputed next time
         # it is called in the inversion
         self.reg._W = None
+        self.reg._Wsmooth = None
 
 class Update_lin_PreCond(InversionDirective):
     """
     Create a Jacobi preconditioner for the linear problem
     """
     onlyOnStart=False
-    
+
     def initialize(self):
-    
+
         if getattr(self.opt, 'approxHinv', None) is None:
             # Update the pre-conditioner
             diagA = np.sum(self.prob.G**2.,axis=0) + self.invProb.beta*(self.reg.W.T*self.reg.W).diagonal() #* (self.reg.mapping * np.ones(self.reg.curModel.size))**2.
             PC     = Utils.sdiag((self.prob.mapping.deriv(None).T *diagA)**-1.)
             self.opt.approxHinv = PC
-            
+
     def endIter(self):
         # Cool the threshold parameter
         if self.onlyOnStart==True:
             return
-            
+
         if getattr(self.opt, 'approxHinv', None) is not None:
             # Update the pre-conditioner
             diagA = np.sum(self.prob.G**2.,axis=0) + self.invProb.beta*(self.reg.W.T*self.reg.W).diagonal() #* (self.reg.mapping * np.ones(self.reg.curModel.size))**2.