added timing to gaussian filter

parallel.py

@@ -304,6 +304,7 @@ class PPP:
     def gaussian_filter(self,key,sigma,truncate=4.0,key_out=None,iterate=False):
         '''Applies a gaussian filter to a field as in-place operation. Sigma is the std of the filter in terms of grid width.'''
         import numpy as np
+        from mpi4py import MPI
         if key_out is None:
             key_out = key
         if key!=key_out:
@@ -328,7 +329,8 @@ class PPP:
                 "increase number of ghost cells. {}".format(radius)
             parprint('Gaussian filter: iterations={}, stencil radius={}'.format(niter,radius))
         for iiter in range(niter):
-            parprint('Iter #{:d}'.format(iiter))
+            parprint('Iter #{:d}: '.format(iiter),end='')
+            tbeg = MPI.Wtime()
             # Filter field: if key_out is None, perform operation inplace
             self.field[key_out] = self.field[key].gaussian_filter(sigma,
                     truncate=truncate,only_keep_interior=False)
@@ -337,6 +339,7 @@ class PPP:
             self.impose_boundary_conditions(key_out)
             # Iterate inplace from now on
             key = key_out
+            parprint('{:g} sec'.format(MPI.Wtime()-tbeg))
 
     def broadcast(self,key,operation,arg,key_out=None):
         '''Broadcasts an operation involving a scalar or matrix on