added default behavior, to allow for unhandled backends, such as 'MacOSX'

IPython/lib/pylabtools.py

@@ -1,147 +1,147 b''
 # -*- coding: utf-8 -*-
 """Pylab (matplotlib) support utilities.
 
 Authors
 -------
 Fernando Perez.
 """
 
 #-----------------------------------------------------------------------------
 #  Copyright (C) 2009  The IPython Development Team
 #
 #  Distributed under the terms of the BSD License.  The full license is in
 #  the file COPYING, distributed as part of this software.
 #-----------------------------------------------------------------------------
 
 #-----------------------------------------------------------------------------
 # Imports
 #-----------------------------------------------------------------------------
 
 from IPython.utils.decorators import flag_calls
 
 #-----------------------------------------------------------------------------
 # Main classes and functions
 #-----------------------------------------------------------------------------
 
 def pylab_activate(user_ns, gui=None, import_all=True):
     """Activate pylab mode in the user's namespace.
 
     Loads and initializes numpy, matplotlib and friends for interactive use.
 
     Parameters
     ----------
     user_ns : dict
       Namespace where the imports will occur.
 
     gui : optional, string
       A valid gui name following the conventions of the %gui magic.
 
     import_all : optional, boolean
       If true, an 'import *' is done from numpy and pylab.
 
     Returns
     -------
     The actual gui used (if not given as input, it was obtained from matplotlib
     itself, and will be needed next to configure IPython's gui integration.
     """
 
     # Initialize matplotlib to interactive mode always
     import matplotlib
 
     # If user specifies a GUI, that dictates the backend, otherwise we read the
     # user's mpl default from the mpl rc structure
     g2b = {'tk': 'TkAgg',
            'gtk': 'GTKAgg',
            'wx': 'WXAgg',
            'qt': 'Qt4Agg', # qt3 not supported
            'qt4': 'Qt4Agg' }
 
     if gui:
         # select backend based on requested gui
         backend = g2b[gui]
     else:
         backend = matplotlib.rcParams['backend']
         # In this case, we need to find what the appropriate gui selection call
         # should be for IPython, so we can activate inputhook accordingly
         b2g = dict(zip(g2b.values(),g2b.keys()))
-        gui = b2g[backend]
+        gui = b2g.get(backend, None)
 
     # We must set the desired backend before importing pylab
     matplotlib.use(backend)
     
     # This must be imported last in the matplotlib series, after
     # backend/interactivity choices have been made
     import matplotlib.pylab as pylab
 
     # XXX For now leave this commented out, but depending on discussions with
     # mpl-dev, we may be able to allow interactive switching...
     #import matplotlib.pyplot
     #matplotlib.pyplot.switch_backend(backend)
 
     pylab.show._needmain = False
     # We need to detect at runtime whether show() is called by the user.
     # For this, we wrap it into a decorator which adds a 'called' flag.
     pylab.draw_if_interactive = flag_calls(pylab.draw_if_interactive)
 
     # Import numpy as np/pyplot as plt are conventions we're trying to
     # somewhat standardize on.  Making them available to users by default
     # will greatly help this. 
     exec ("import numpy\n"
           "import matplotlib\n"
           "from matplotlib import pylab, mlab, pyplot\n"
           "np = numpy\n"
           "plt = pyplot\n"
           ) in user_ns
 
     if import_all:
         exec("from matplotlib.pylab import *\n"
              "from numpy import *\n") in user_ns
 
     matplotlib.interactive(True)
 
     print """
 Welcome to pylab, a matplotlib-based Python environment [backend: %s].
 For more information, type 'help(pylab)'.""" % backend
     
     return gui
 
 # We need a little factory function here to create the closure where
 # safe_execfile can live.
 def mpl_runner(safe_execfile):
     """Factory to return a matplotlib-enabled runner for %run.
 
     Parameters
     ----------
     safe_execfile : function
       This must be a function with the same interface as the
       :meth:`safe_execfile` method of IPython.
 
     Returns
     -------
     A function suitable for use as the ``runner`` argument of the %run magic
     function.
     """
     
     def mpl_execfile(fname,*where,**kw):
         """matplotlib-aware wrapper around safe_execfile.
 
         Its interface is identical to that of the :func:`execfile` builtin.
 
         This is ultimately a call to execfile(), but wrapped in safeties to
         properly handle interactive rendering."""
 
         import matplotlib
         import matplotlib.pylab as pylab
 
         #print '*** Matplotlib runner ***' # dbg
         # turn off rendering until end of script
         is_interactive = matplotlib.rcParams['interactive']
         matplotlib.interactive(False)
         safe_execfile(fname,*where,**kw)
         matplotlib.interactive(is_interactive)
         # make rendering call now, if the user tried to do it
         if pylab.draw_if_interactive.called:
             pylab.draw()
             pylab.draw_if_interactive.called = False
 
     return mpl_execfile