# -*- coding: utf-8 -*- """Pylab (matplotlib) support utilities. Authors ------- * Fernando Perez. * Brian Granger """ from __future__ import print_function #----------------------------------------------------------------------------- # 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 #----------------------------------------------------------------------------- import sys from io import BytesIO from IPython.core.display import _pngxy 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', 'gtk3': 'GTK3Agg', 'wx': 'WXAgg', 'qt': 'Qt4Agg', # qt3 not supported 'qt4': 'Qt4Agg', 'osx': 'MacOSX', 'inline' : 'module://IPython.kernel.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())) # Our tests expect backend2gui to just return 'qt' backend2gui['Qt4Agg'] = 'qt' # 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['GTK3Cairo'] = 'gtk3' 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', quality=90): """Convert a figure to svg, png or jpg for inline display. Quality is only relevant for jpg. """ from matplotlib import rcParams # 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 and not fig.lines: return fc = fig.get_facecolor() ec = fig.get_edgecolor() bytes_io = BytesIO() dpi = rcParams['savefig.dpi'] if fmt == 'retina': dpi = dpi * 2 fmt = 'png' fig.canvas.print_figure(bytes_io, format=fmt, bbox_inches='tight', facecolor=fc, edgecolor=ec, dpi=dpi, quality=quality) data = bytes_io.getvalue() return data def retina_figure(fig): """format a figure as a pixel-doubled (retina) PNG""" pngdata = print_figure(fig, fmt='retina') w, h = _pngxy(pngdata) metadata = dict(width=w//2, height=h//2) return pngdata, metadata # 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, quality): """Select figure format for inline backend, can be 'png', 'retina', 'jpg', or 'svg'. Using this method ensures only one figure format is active at a time. """ from matplotlib.figure import Figure from IPython.kernel.zmq.pylab import backend_inline svg_formatter = shell.display_formatter.formatters['image/svg+xml'] png_formatter = shell.display_formatter.formatters['image/png'] jpg_formatter = shell.display_formatter.formatters['image/jpeg'] [ f.type_printers.pop(Figure, None) for f in {svg_formatter, png_formatter, jpg_formatter} ] if fmt == 'png': png_formatter.for_type(Figure, lambda fig: print_figure(fig, 'png')) elif fmt in ('png2x', 'retina'): png_formatter.for_type(Figure, retina_figure) elif fmt in ('jpg', 'jpeg'): jpg_formatter.for_type(Figure, lambda fig: print_figure(fig, 'jpg', quality)) elif fmt == 'svg': svg_formatter.for_type(Figure, lambda fig: print_figure(fig, 'svg')) else: raise ValueError("supported formats are: 'png', 'retina', 'svg', 'jpg', 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, gui_select=None): """Given a gui string return the gui and mpl backend. Parameters ---------- gui : str Can be one of ('tk','gtk','wx','qt','qt4','inline'). gui_select : str Can be one of ('tk','gtk','wx','qt','qt4','inline'). This is any gui already selected by the shell. Returns ------- A tuple of (gui, backend) where backend is one of ('TkAgg','GTKAgg', 'WXAgg','Qt4Agg','module://IPython.kernel.zmq.pylab.backend_inline'). """ import matplotlib if gui and gui != 'auto': # select backend based on requested gui backend = backends[gui] else: # We need to read the backend from the original data structure, *not* # from mpl.rcParams, since a prior invocation of %matplotlib may have # overwritten that. # WARNING: this assumes matplotlib 1.1 or newer!! backend = matplotlib.rcParamsOrig['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) # If we have already had a gui active, we need it and inline are the # ones allowed. if gui_select and gui != gui_select: gui = gui_select backend = backends[gui] return gui, backend def activate_matplotlib(backend): """Activate the given backend and set interactive to True.""" import matplotlib matplotlib.interactive(True) # Matplotlib had a bug where even switch_backend could not force # the rcParam to update. This needs to be set *before* the module # magic of switch_backend(). matplotlib.rcParams['backend'] = backend import matplotlib.pyplot matplotlib.pyplot.switch_backend(backend) # This must be imported last in the matplotlib series, after # backend/interactivity choices have been made import matplotlib.pylab as pylab 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, import_all=True): """Populate the namespace with pylab-related values. Imports matplotlib, pylab, numpy, and everything from pylab and numpy. Also imports a few names from IPython (figsize, display, getfigs) """ # 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, user_ns) if import_all: s = ("from matplotlib.pylab import *\n" "from numpy import *\n") exec(s, user_ns) # IPython symbols to add user_ns['figsize'] = figsize from IPython.core.display import display # Add display and getfigs to the user's namespace user_ns['display'] = display user_ns['getfigs'] = getfigs def configure_inline_support(shell, backend): """Configure an IPython shell object for matplotlib use. Parameters ---------- shell : InteractiveShell instance backend : matplotlib backend """ # 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. # Note: if we can't load the inline backend, then there's no point # continuing (such as in terminal-only shells in environments without # zeromq available). try: from IPython.kernel.zmq.pylab.backend_inline import InlineBackend except ImportError: return from matplotlib import pyplot cfg = InlineBackend.instance(parent=shell) cfg.shell = shell if cfg not in shell.configurables: shell.configurables.append(cfg) if backend == backends['inline']: from IPython.kernel.zmq.pylab.backend_inline import flush_figures shell.register_post_execute(flush_figures) # Save rcParams that will be overwrittern shell._saved_rcParams = dict() for k in cfg.rc: shell._saved_rcParams[k] = pyplot.rcParams[k] # load inline_rc pyplot.rcParams.update(cfg.rc) else: from IPython.kernel.zmq.pylab.backend_inline import flush_figures if flush_figures in shell._post_execute: shell._post_execute.pop(flush_figures) if hasattr(shell, '_saved_rcParams'): pyplot.rcParams.update(shell._saved_rcParams) del shell._saved_rcParams # Setup the default figure format select_figure_format(shell, cfg.figure_format, cfg.quality)