misc example updates

examples/fdfd1.py

@@ -1,4 +1,5 @@
 import importlib
+import logging
 import numpy
 from numpy.linalg import norm
 from matplotlib import pyplot, colors
@@ -6,12 +7,14 @@ import logging
 
 import meanas
 from meanas import fdtd
-from meanas.fdmath import vec, unvec
+from meanas.fdmath import vec, unvec, fdfield_t
 from meanas.fdfd import waveguide_3d, functional, scpml, operators
 from meanas.fdfd.solvers import generic as generic_solver
 
 import gridlock
 
+from matplotlib import pyplot
+
 
 logging.basicConfig(level=logging.DEBUG)
 logging.getLogger('matplotlib').setLevel(logging.WARNING)