More guards and documentation for valid 'adjustable' values.

efiring · efiring · commit 2371be7e71f9 · 2018-01-05T16:11:59.000-10:00
diff --git a/lib/matplotlib/axes/_base.py b/lib/matplotlib/axes/_base.py
@@ -1324,7 +1324,7 @@ def set_aspect(self, aspect, adjustable=None, anchor=None, share=False):
         self.set_adjustable(adjustable, share=share)  # Handle sharing.
 
         if anchor is not None:
-            self.set_anchor(anchor)  # Also needs a "share" kwarg?
+            self.set_anchor(anchor, share=share)
         self.stale = True
 
     def get_adjustable(self):
@@ -1351,10 +1351,22 @@ def set_adjustable(self, adjustable, share=False):
         --------
         matplotlib.axes.Axes.set_aspect
             for a description of aspect handling.
+
+        Notes
+        -----
+        Shared Axes (of which twinned Axes are a special case)
+        impose restrictions on how aspect ratios can be imposed.
+        For twinned Axes, use 'datalim'.  For Axes that share both
+        x and y, use 'box'.  Otherwise, either 'datalim' or 'box'
+        may be used.  These limitations are partly a requirement
+        to avoid over-specification, and partly a result of the
+        particular implementation we are currently using, in
+        which the adjustments for aspect ratios are done sequentially
+        and independently on each Axes as it is drawn.
         """
         if adjustable == 'box-forced':
             warnings.warn("The 'box-forced' keyword argument is deprecated"
-                          " since 2.2.", mplDeprecation)
+                          " since 2.2.", cbook.mplDeprecation)
         if adjustable not in ('box', 'datalim', 'box-forced'):
             raise ValueError("argument must be 'box', or 'datalim'")
         if share:
@@ -1379,7 +1391,7 @@ def get_anchor(self):
         """
         return self._anchor
 
-    def set_anchor(self, anchor):
+    def set_anchor(self, anchor, share=False):
         """
         Define the anchor location.
 
@@ -1417,16 +1429,26 @@ def set_anchor(self, anchor):
               | 'SW' | 'S'  | 'SE' |
               +------+------+------+
 
+        share : bool, optional
+            If ``True``, apply the settings to all shared Axes.
+            Default is ``False``.
+
         See Also
         --------
         matplotlib.axes.Axes.set_aspect
             for a description of aspect handling.
         """
-        if anchor in mtransforms.Bbox.coefs or len(anchor) == 2:
-            self._anchor = anchor
-        else:
+        if not (anchor in mtransforms.Bbox.coefs or len(anchor) == 2):
             raise ValueError('argument must be among %s' %
                              ', '.join(mtransforms.Bbox.coefs))
+        if share:
+            axes = set(self._shared_x_axes.get_siblings(self)
+                       + self._shared_y_axes.get_siblings(self))
+        else:
+            axes = [self]
+        for ax in axes:
+            ax._anchor = anchor
+
         self.stale = True
 
     def get_data_ratio(self):
@@ -1516,6 +1538,9 @@ def apply_aspect(self, position=None):
         figW, figH = self.get_figure().get_size_inches()
         fig_aspect = figH / figW
         if self._adjustable in ['box', 'box-forced']:
+            if self in self._twinned_axes:
+                raise RuntimeError("Adjustable 'box' is not allowed in a"
+                                   " twinned Axes.  Use 'datalim' instead.")
             if aspect_scale_mode == "log":
                 box_aspect = A * self.get_data_ratio_log()
             else:
@@ -4122,13 +4147,16 @@ def get_tightbbox(self, renderer, call_axes_locator=True):
 
     def _make_twin_axes(self, *kl, **kwargs):
         """
-        make a twinx axes of self. This is used for twinx and twiny.
+        Make a twinx axes of self. This is used for twinx and twiny.
         """
         # Typically, SubplotBase._make_twin_axes is called instead of this.
+        # There is also an override in axes_grid1/axes_divider.py.
+        if 'sharex' in kwargs and 'sharey' in kwargs:
+            raise ValueError("Twinned Axes may share only one axis.")
         ax2 = self.figure.add_axes(self.get_position(True), *kl, **kwargs)
         ## do not touch every thing shared, just this and it's twin.
-        #self.set_adjustable('datalim')
-        #ax2.set_adjustable('datalim')
+        self.set_adjustable('datalim')
+        ax2.set_adjustable('datalim')
         self._twinned_axes.join(self, ax2)
         return ax2
 
diff --git a/lib/matplotlib/axes/_subplots.py b/lib/matplotlib/axes/_subplots.py
@@ -144,16 +144,20 @@ def label_outer(self):
 
     def _make_twin_axes(self, *kl, **kwargs):
         """
-        make a twinx axes of self. This is used for twinx and twiny.
+        Make a twinx axes of self. This is used for twinx and twiny.
         """
         from matplotlib.projections import process_projection_requirements
+        if 'sharex' in kwargs and 'sharey' in kwargs:
+            raise ValueError("Twinned Axes may share only one axis.")
         kl = (self.get_subplotspec(),) + kl
         projection_class, kwargs, key = process_projection_requirements(
             self.figure, *kl, **kwargs)
 
         ax2 = subplot_class_factory(projection_class)(self.figure,
                                                       *kl, **kwargs)
         self.figure.add_subplot(ax2)
+        self.set_adjustable('datalim')
+        ax2.set_adjustable('datalim')
         self._twinned_axes.join(self, ax2)
         return ax2
 
diff --git a/lib/mpl_toolkits/axes_grid1/axes_divider.py b/lib/mpl_toolkits/axes_grid1/axes_divider.py
@@ -915,9 +915,13 @@ def _make_twin_axes(self, *kl, **kwargs):
         Need to overload so that twinx/twiny will work with
         these axes.
         """
+        if 'sharex' in kwargs and 'sharey' in kwargs:
+            raise ValueError("Twinned Axes may share only one axis.")
         ax2 = type(self)(self.figure, self.get_position(True), *kl, **kwargs)
         ax2.set_axes_locator(self.get_axes_locator())
         self.figure.add_axes(ax2)
+        self.set_adjustable('datalim')
+        ax2.set_adjustable('datalim')
         self._twinned_axes.join(self, ax2)
         return ax2
 
