added rcParam for x and y margin

Addresses issue matplotlib#1766

Author: tacaswell

lib/matplotlib/axes.py

@@ -901,8 +901,8 @@ def cla(self):
 
         self._autoscaleXon = True
         self._autoscaleYon = True
-        self._xmargin = 0
-        self._ymargin = 0
+        self._xmargin = rcParams['axes.xmargin']
+        self._ymargin = rcParams['axes.ymargin']
         self._tight = False
         self._update_transScale()  # needed?
 
@@ -9076,7 +9076,7 @@ def matshow(self, Z, **kwargs):
         return im
 
     def get_default_bbox_extra_artists(self):
-        return [artist for artist in self.get_children() 
+        return [artist for artist in self.get_children()
                 if artist.get_visible()]
 
     def get_tightbbox(self, renderer, call_axes_locator=True):

lib/matplotlib/rcsetup.py

@@ -579,6 +579,12 @@ def __call__(self, s):
     'axes.color_cycle': [['b', 'g', 'r', 'c', 'm', 'y', 'k'],
                          validate_colorlist],  # cycle of plot
                                                # line colors
+    'axes.xmargin': [0, ValidateInterval(0, 1,
+                                         closedmin=True,
+                                         closedmax=True)],  # margin added to xaxis
+    'axes.ymargin': [0, ValidateInterval(0, 1,
+                                         closedmin=True,
+                                         closedmax=True)],# margin added to yaxis
 
     'polaraxes.grid': [True, validate_bool],  # display polar grid or
                                                      # not

matplotlibrc.template

@@ -250,6 +250,8 @@ text.hinting_factor : 8 # Specifies the amount of softness for hinting in the
                                             # as list of string colorspecs:
                                             # single letter, long name, or
                                             # web-style hex
+#axes.xmargin        : 0  # x margin.  See `axes.Axes.margins`
+#axes.ymargin        : 0  # y margin See `axes.Axes.margins`
 
 #polaraxes.grid      : True    # display grid on polar axes
 #axes3d.grid         : True    # display grid on 3d axes
@@ -451,7 +453,7 @@ text.hinting_factor : 8 # Specifies the amount of softness for hinting in the
 #animation.avconv_path: 'avconv'   # Path to avconv binary. Without full path
                                    # $PATH is searched
 #animation.avconv_args: ''         # Additional arguments to pass to avconv
-#animation.mencoder_path: 'mencoder' 
+#animation.mencoder_path: 'mencoder'
                                    # Path to mencoder binary. Without full path
                                    # $PATH is searched
 #animation.mencoder_args: ''       # Additional arguments to pass to mencoder