Adding support for multiple figure formats in InlineBackend.

IPython/core/pylabtools.py

@@ -25,6 +25,7 b' from io import BytesIO'
 
 from IPython.core.display import _pngxy
 from IPython.utils.decorators import flag_calls
+from IPython.utils import py3compat
 
 # If user specifies a GUI, that dictates the backend, otherwise we read the
 # user's mpl default from the mpl rc structure
@@ -165,10 +166,15 b' def mpl_runner(safe_execfile):'
     return mpl_execfile
 
 
-def select_figure_format(shell, fmt, quality=90):
-    """Select figure format for inline backend, can be 'png', 'retina', 'jpg', or 'svg'.
+def select_figure_format(shell, formats, quality=90):
+    """Select figure formats for the inline backend.
 
-    Using this method ensures only one figure format is active at a time.
+    Parameters
+    ==========
+    shell : InteractiveShell
+        The main IPython instance
+    formats : list
+        One or a set of figure formats to enable: 'png', 'retina', 'jpeg', 'svg', 'pdf'.
     """
     from matplotlib.figure import Figure
     from IPython.kernel.zmq.pylab import backend_inline
@@ -176,9 +182,14 b' def select_figure_format(shell, fmt, quality=90):'
     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']
+    pdf_formatter = shell.display_formatter.formatters['application/pdf']
+
+    if isinstance(formats, py3compat.string_types):
+        formats = {formats}
 
     [ f.type_printers.pop(Figure, None) for f in {svg_formatter, png_formatter, jpg_formatter} ]
 
+    for fmt in formats:
     if fmt == 'png':
         png_formatter.for_type(Figure, lambda fig: print_figure(fig, 'png'))
     elif fmt in ('png2x', 'retina'):
@@ -187,11 +198,10 b' def select_figure_format(shell, fmt, quality=90):'
         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'))
+        elif fmt == 'pdf':
+            pdf_formatter.for_type(Figure, lambda fig: print_figure(fig, 'pdf'))
     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
+            raise ValueError("supported formats are: 'png', 'retina', 'svg', 'jpg', 'pdf' not %r" % fmt)
 
 #-----------------------------------------------------------------------------
 # Code for initializing matplotlib and importing pylab
@@ -342,5 +352,5 b' def configure_inline_support(shell, backend):'
             del shell._saved_rcParams
 
     # Setup the default figure format
-    select_figure_format(shell, cfg.figure_format, cfg.quality)
+    select_figure_format(shell, cfg.figure_formats, cfg.quality)
 

IPython/kernel/zmq/pylab/config.py

@@ -14,7 +14,9 b' This module does not import anything from matplotlib.'
 #-----------------------------------------------------------------------------
 
 from IPython.config.configurable import SingletonConfigurable
-from IPython.utils.traitlets import Dict, Instance, CaselessStrEnum, Bool, Int, TraitError
+from IPython.utils.traitlets import (
+    Dict, Instance, CaselessStrEnum, Set, Bool, Int, TraitError, Unicode
+)
 from IPython.utils.warn import warn
 
 #-----------------------------------------------------------------------------
@@ -63,15 +65,13 b' class InlineBackend(InlineBackendConfig):'
         inline backend."""
     )
 
+    figure_formats = Set({'png'}, config=True,
+                          help="""A set of figure formats to enable: 'png', 
+                          'retina', 'jpeg', 'svg', 'pdf'.""")
 
-    figure_format = CaselessStrEnum(['svg', 'png', 'retina', 'jpg'],
-                                    default_value='png', config=True,
-                                    help="""The image format for figures with the inline
-                                    backend. JPEG requires the PIL/Pillow library.""")
-
-    def _figure_format_changed(self, name, old, new):
+    def _figure_formats_changed(self, name, old, new):
         from IPython.core.pylabtools import select_figure_format
-        if new in {"jpg", "jpeg"}:
+        if 'jpg' in new or 'jpeg' in new:
             if not pil_available():
                 raise TraitError("Requires PIL/Pillow for JPG figures")
         if self.shell is None:
@@ -79,6 +79,12 b' class InlineBackend(InlineBackendConfig):'
         else:
             select_figure_format(self.shell, new)
 
+    figure_format = Unicode()
+
+    def _figure_format_changed(self, name, old, new):
+        if new:
+            self.figure_formats = {new}
+
     quality = Int(default_value=90, config=True,
                   help="Quality of compression [10-100], currently for lossy JPEG only.")