Implemented style cycling using cycler.

* New rcparam 'axes.style_cycle' * Deprecate rcparam 'axes.color_cycle' * 'axes.style_cycle' can be a cycler object or string repr * Enables setting of just about any property
matplotlib · tacaswell · Aug 29, 2015 · Jul 11, 2015 · Jul 12, 2015 · Jul 14, 2015
commit e3c09518bca3e1e4f941c8f54c788e970f0876e1
diff --git a/lib/matplotlib/axes/_base.py b/lib/matplotlib/axes/_base.py
@@ -9,6 +9,7 @@
 import math
 from operator import itemgetter
 
+from cycler import cycler
 import numpy as np
 from numpy import ma
 
@@ -138,20 +139,25 @@ class _process_plot_var_args(object):
     def __init__(self, axes, command='plot'):
         self.axes = axes
         self.command = command
-        self.set_color_cycle()
+        self.set_style_cycle()
 
     def __getstate__(self):
         # note: it is not possible to pickle a itertools.cycle instance
         return {'axes': self.axes, 'command': self.command}
 
     def __setstate__(self, state):
         self.__dict__ = state.copy()
-        self.set_color_cycle()
-
-    def set_color_cycle(self, clist=None):
-        if clist is None:
-            clist = rcParams['axes.color_cycle']
-        self.color_cycle = itertools.cycle(clist)
+        self.set_style_cycle()
+
+    def set_style_cycle(self, style_cycler=None):
+        if style_cycler is None:
+            style_cycler = rcParams['axes.style_cycle']
+            if style_cycler is None and 'axes.color_cycle' in rcParams:
+                clist = rcParams['axes.color_cycle']
+                style_cycler = cycler('color', clist)
+        self.style_cycler = itertools.cycle(style_cycler)
+        # Make a copy
+        self._style_keys = list(style_cycler.keys)
 
     def __call__(self, *args, **kwargs):
 
@@ -229,24 +235,37 @@ def _xy_from_xy(self, x, y):
             y = y[:, np.newaxis]
         return x, y
 
+    def _setdefaults(self, kw, kwargs):
+        # Only advance the cycler if the cycler
+        # has information that is not specified
+        # in the supplied kw and kwargs dicts
+        if any([kw.get(k, None) is None and kwargs.get(k, None) is None
+                for k in self._style_keys]):
+            default_dict = six.next(self.style_cycler)
+        else:
+            default_dict = None
+
+        for k in self._style_keys:
+            if (default_dict is not None and
+                    kw.get(k, None) is None and
+                    kwargs.get(k, None) is None):
+                kwargs[k] = kw[k] = default_dict[k]
+
     def _makeline(self, x, y, kw, kwargs):
         kw = kw.copy()  # Don't modify the original kw.
         kwargs = kwargs.copy()
-        if kw.get('color', None) is None and kwargs.get('color', None) is None:
-            kwargs['color'] = kw['color'] = six.next(self.color_cycle)
-            # (can't use setdefault because it always evaluates
-            # its second argument)
-        seg = mlines.Line2D(x, y,
-                            **kw
-                            )
+        self._setdefaults(kw, kwargs)
+        seg = mlines.Line2D(x, y, **kw)
         self.set_lineprops(seg, **kwargs)
         return seg
 
     def _makefill(self, x, y, kw, kwargs):
-        try:
-            facecolor = kw['color']
-        except KeyError:
-            facecolor = six.next(self.color_cycle)
+        kw = kw.copy()  # Don't modify the original kw.
+        kwargs = kwargs.copy()
+        # Might be problematic with fallback names such as
+        # 'facecolor' and such. Possibly fixed by traitlets?
+        self._setdefaults(kw, kwargs)
+        facecolor = kw['color']
         seg = mpatches.Polygon(np.hstack((x[:, np.newaxis],
                                           y[:, np.newaxis])),
                                facecolor=facecolor,

diff --git a/lib/matplotlib/rcsetup.py b/lib/matplotlib/rcsetup.py
@@ -23,6 +23,8 @@
 from matplotlib.fontconfig_pattern import parse_fontconfig_pattern
 from matplotlib.colors import is_color_like
 
+from cycler import cycler, Cycler
+
 #interactive_bk = ['gtk', 'gtkagg', 'gtkcairo', 'qt4agg',
 #                  'tkagg', 'wx', 'wxagg', 'cocoaagg', 'webagg']
 # The capitalized forms are needed for ipython at present; this may
@@ -299,6 +301,12 @@ def validate_color(s):
 
     raise ValueError('%s does not look like a color arg%s' % (s, msg))
 
+def deprecate_axes_colorcycle(value):
+    warnings.warn("axes.color_cycle is deprecated.  Use axes.style_cycle "
+                  "instead. Will be removed in 2.1.0")
+    return validate_colorlist(value)
+
+
 
 def validate_colorlist(s):
     'return a list of colorspecs'
@@ -310,6 +318,25 @@ def validate_colorlist(s):
         msg = "'s' must be of type [ string | list | tuple ]"
         raise ValueError(msg)
 
+def validate_cycler(s):
+    'return a cycler object from a string repr or the object itself'
+    if isinstance(s, six.string_types):
+        try:
+            # TODO: We might want to rethink this...
+            cycler_inst = eval(s, {'cycler': cycler, 'Cycler': Cycler})
+        except BaseException as e:
+            raise ValueError("'%s' is not a valid cycler construction: %s" %
+                             (s, e))
+    elif isinstance(s, Cycler):
+        cycler_inst = s
+    else:
+        raise ValueError("object was not a string or Cycler instance: %s" % s)
+
+    # TODO: apply validation to the cycled elements
+    # probably doable via traitlets
+
+    return cycler_inst
+
 def validate_stringlist(s):
     'return a list'
     if isinstance(s, six.string_types):
@@ -750,6 +777,11 @@ def __call__(self, s):
     'axes.color_cycle': [['b', 'g', 'r', 'c', 'm', 'y', 'k'],
                          validate_colorlist],  # cycle of plot
                                                # line colors
+    # This entry can be either a cycler object or a
+    # string repr of a cycler-object, which gets eval()'ed
+    # to create the object.
+    'axes.style_cycle': [cycler('color', 'bgrcmyk'),
+                         validate_cycler],
     'axes.xmargin': [0, ValidateInterval(0, 1,
                                          closedmin=True,
                                          closedmax=True)],  # margin added to xaxis