# -*- coding: utf-8 -*- """Pylab (matplotlib) support utilities. Authors ------- * Fernando Perez. * Brian Granger """ #----------------------------------------------------------------------------- # 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 io import BytesIO from IPython.utils.decorators import flag_calls # If user specifies a GUI, that dictates the backend, otherwise we read the # user's mpl default from the mpl rc structure backends = {'tk': 'TkAgg', 'gtk': 'GTKAgg', 'wx': 'WXAgg', 'qt': 'Qt4Agg', # qt3 not supported 'qt4': 'Qt4Agg', 'osx': 'MacOSX', 'inline' : 'module://IPython.zmq.pylab.backend_inline'} # We also need a reverse backends2guis mapping that will properly choose which # GUI support to activate based on the desired matplotlib backend. For the # most part it's just a reverse of the above dict, but we also need to add a # few others that map to the same GUI manually: backend2gui = dict(zip(backends.values(), backends.keys())) # In the reverse mapping, there are a few extra valid matplotlib backends that # map to the same GUI support backend2gui['GTK'] = backend2gui['GTKCairo'] = 'gtk' backend2gui['WX'] = 'wx' backend2gui['CocoaAgg'] = 'osx' #----------------------------------------------------------------------------- # Matplotlib utilities #----------------------------------------------------------------------------- def getfigs(*fig_nums): """Get a list of matplotlib figures by figure numbers. If no arguments are given, all available figures are returned. If the argument list contains references to invalid figures, a warning is printed but the function continues pasting further figures. Parameters ---------- figs : tuple A tuple of ints giving the figure numbers of the figures to return. """ from matplotlib._pylab_helpers import Gcf if not fig_nums: fig_managers = Gcf.get_all_fig_managers() return [fm.canvas.figure for fm in fig_managers] else: figs = [] for num in fig_nums: f = Gcf.figs.get(num) if f is None: print('Warning: figure %s not available.' % num) else: figs.append(f.canvas.figure) return figs def figsize(sizex, sizey): """Set the default figure size to be [sizex, sizey]. This is just an easy to remember, convenience wrapper that sets:: matplotlib.rcParams['figure.figsize'] = [sizex, sizey] """ import matplotlib matplotlib.rcParams['figure.figsize'] = [sizex, sizey] def print_figure(fig, fmt='png'): """Convert a figure to svg or png for inline display.""" # When there's an empty figure, we shouldn't return anything, otherwise we # get big blank areas in the qt console. if not fig.axes: return fc = fig.get_facecolor() ec = fig.get_edgecolor() fig.set_facecolor('white') fig.set_edgecolor('white') try: bytes_io = BytesIO() fig.canvas.print_figure(bytes_io, format=fmt, bbox_inches='tight') data = bytes_io.getvalue() finally: fig.set_facecolor(fc) fig.set_edgecolor(ec) return data # 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 def select_figure_format(shell, fmt): """Select figure format for inline backend, either 'png' or 'svg'. Using this method ensures only one figure format is active at a time. """ from matplotlib.figure import Figure from IPython.zmq.pylab import backend_inline svg_formatter = shell.display_formatter.formatters['image/svg+xml'] png_formatter = shell.display_formatter.formatters['image/png'] if fmt=='png': svg_formatter.type_printers.pop(Figure, None) png_formatter.for_type(Figure, lambda fig: print_figure(fig, 'png')) elif fmt=='svg': png_formatter.type_printers.pop(Figure, None) svg_formatter.for_type(Figure, lambda fig: print_figure(fig, 'svg')) else: raise ValueError("supported formats are: 'png', 'svg', not %r"%fmt) # set the format to be used in the backend() backend_inline._figure_format = fmt #----------------------------------------------------------------------------- # Code for initializing matplotlib and importing pylab #----------------------------------------------------------------------------- def find_gui_and_backend(gui=None): """Given a gui string return the gui and mpl backend. Parameters ---------- gui : str Can be one of ('tk','gtk','wx','qt','qt4','inline'). Returns ------- A tuple of (gui, backend) where backend is one of ('TkAgg','GTKAgg', 'WXAgg','Qt4Agg','module://IPython.zmq.pylab.backend_inline'). """ import matplotlib if gui and gui != 'auto': # select backend based on requested gui backend = backends[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 gui = backend2gui.get(backend, None) return gui, backend def activate_matplotlib(backend): """Activate the given backend and set interactive to True.""" import matplotlib if backend.startswith('module://'): # Work around bug in matplotlib: matplotlib.use converts the # backend_id to lowercase even if a module name is specified! matplotlib.rcParams['backend'] = backend else: matplotlib.use(backend) matplotlib.interactive(True) # 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) def import_pylab(user_ns, backend, import_all=True, shell=None): """Import the standard pylab symbols into user_ns.""" # 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. s = ("import numpy\n" "import matplotlib\n" "from matplotlib import pylab, mlab, pyplot\n" "np = numpy\n" "plt = pyplot\n" ) exec s in user_ns if shell is not None: exec s in shell.user_ns_hidden # If using our svg payload backend, register the post-execution # function that will pick up the results for display. This can only be # done with access to the real shell object. # from IPython.zmq.pylab.backend_inline import InlineBackend cfg = InlineBackend.instance(config=shell.config) cfg.shell = shell if cfg not in shell.configurables: shell.configurables.append(cfg) if backend == backends['inline']: from IPython.zmq.pylab.backend_inline import flush_figures from matplotlib import pyplot shell.register_post_execute(flush_figures) # load inline_rc pyplot.rcParams.update(cfg.rc) # Add 'figsize' to pyplot and to the user's namespace user_ns['figsize'] = pyplot.figsize = figsize shell.user_ns_hidden['figsize'] = figsize # Setup the default figure format fmt = cfg.figure_format select_figure_format(shell, fmt) # The old pastefig function has been replaced by display from IPython.core.display import display # Add display and display_png to the user's namespace user_ns['display'] = display shell.user_ns_hidden['display'] = display user_ns['getfigs'] = getfigs shell.user_ns_hidden['getfigs'] = getfigs if import_all: s = ("from matplotlib.pylab import *\n" "from numpy import *\n") exec s in user_ns if shell is not None: exec s in shell.user_ns_hidden def pylab_activate(user_ns, gui=None, import_all=True, shell=None): """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. """ gui, backend = find_gui_and_backend(gui) activate_matplotlib(backend) import_pylab(user_ns, backend, import_all, shell) print """ Welcome to pylab, a matplotlib-based Python environment [backend: %s]. For more information, type 'help(pylab)'.""" % backend return gui