FIX tick label alignment can now be specified

NelleV · NelleV · commit e274ed9c5d13 · 2017-02-15T10:58:20.000-08:00
This patch adds two new rcParams allowing to set label alignment. The sole reason for the existance of these new parameters is to allow user to reset the style to before 2.0 for testing purposes. More specifically, ytick horizontal alignement was changed in a non backward compatible way. xtick vertical alignement was added for API consistency. closes #7905
diff --git a/doc/users/dflt_style_changes.rst b/doc/users/dflt_style_changes.rst
@@ -15,9 +15,13 @@ values is a single line of python
 
   mpl.style.use('classic')
 
+Note that to revert the position of tick labels, you need in addition to set
+the rcParams `ytick.alignment` to "center".
+
 See :ref:`customizing-with-matplotlibrc-files` for details about how to
 persistently and selectively revert many of these changes.
 
+
 .. contents:: Table of Contents
    :depth: 2
    :local:
diff --git a/lib/matplotlib/axes/_base.py b/lib/matplotlib/axes/_base.py
@@ -731,10 +731,12 @@ def get_xaxis_text1_transform(self, pad_points):
             place axis elements in different locations.
 
         """
+        labels_align = matplotlib.rcParams["xtick.alignment"]
+
         return (self.get_xaxis_transform(which='tick1') +
                 mtransforms.ScaledTranslation(0, -1 * pad_points / 72.0,
                                               self.figure.dpi_scale_trans),
-                "top", "center")
+                "top", labels_align)
 
     def get_xaxis_text2_transform(self, pad_points):
         """
@@ -757,10 +759,11 @@ def get_xaxis_text2_transform(self, pad_points):
             place axis elements in different locations.
 
         """
+        labels_align = matplotlib.rcParams["xtick.alignment"]
         return (self.get_xaxis_transform(which='tick2') +
                 mtransforms.ScaledTranslation(0, pad_points / 72.0,
                                               self.figure.dpi_scale_trans),
-                "bottom", "center")
+                "bottom", labels_align)
 
     def get_yaxis_transform(self, which='grid'):
         """
@@ -808,10 +811,11 @@ def get_yaxis_text1_transform(self, pad_points):
             place axis elements in different locations.
 
         """
+        labels_align = matplotlib.rcParams["ytick.alignment"]
         return (self.get_yaxis_transform(which='tick1') +
                 mtransforms.ScaledTranslation(-1 * pad_points / 72.0, 0,
                                               self.figure.dpi_scale_trans),
-                "center_baseline", "right")
+                labels_align, "right")
 
     def get_yaxis_text2_transform(self, pad_points):
         """
@@ -834,10 +838,12 @@ def get_yaxis_text2_transform(self, pad_points):
             place axis elements in different locations.
 
         """
+        labels_align = matplotlib.rcParams["ytick.alignment"]
+
         return (self.get_yaxis_transform(which='tick2') +
                 mtransforms.ScaledTranslation(pad_points / 72.0, 0,
                                               self.figure.dpi_scale_trans),
-                "center_baseline", "left")
+                labels_align, "left")
 
     def _update_transScale(self):
         self.transScale.set(
@@ -2560,13 +2566,10 @@ def ticklabel_format(self, **kwargs):
                 raise ValueError("scilimits must be a sequence of 2 integers")
         if style[:3] == 'sci':
             sb = True
-        elif style in ['plain', 'comma']:
+        elif style == 'plain':
             sb = False
-            if style == 'plain':
-                cb = False
-            else:
-                cb = True
-                raise NotImplementedError("comma style remains to be added")
+        elif style == 'comma':
+            raise NotImplementedError("comma style remains to be added")
         elif style == '':
             sb = None
         else:
diff --git a/lib/matplotlib/rcsetup.py b/lib/matplotlib/rcsetup.py
@@ -465,6 +465,11 @@ def validate_font_properties(s):
     'verbose',
     ['silent', 'helpful', 'debug', 'debug-annoying'])
 
+_validate_alignment = ValidateInStrings(
+    'alignment',
+    ['center', 'top', 'bottom', 'baseline',
+     'center_baseline'])
+
 def validate_whiskers(s):
     if s=='range':
         return 'range'
@@ -1214,6 +1219,9 @@ def validate_animation_writer_path(p):
     # fontsize of the ytick labels
     'ytick.labelsize':   ['medium', validate_fontsize],
     'ytick.direction':   ['out', six.text_type],            # direction of yticks
+    'ytick.alignment': ["center_baseline", _validate_alignment],
+    'xtick.alignment': ["center", _validate_alignment],
+
 
     'grid.color':        ['#b0b0b0', validate_color],  # grid color
     'grid.linestyle':    ['-', six.text_type],      # solid
diff --git a/lib/matplotlib/tests/baseline_images/test_axes/bar_tick_label_multiple_old_label_alignment.png b/lib/matplotlib/tests/baseline_images/test_axes/bar_tick_label_multiple_old_label_alignment.png
diff --git a/lib/matplotlib/tests/test_axes.py b/lib/matplotlib/tests/test_axes.py
@@ -1143,6 +1143,15 @@ def test_bar_tick_label_multiple():
     ax.bar([1, 2.5], [1, 2], width=[0.2, 0.5], tick_label=['a', 'b'],
            align='center')
 
+@image_comparison(baseline_images=['bar_tick_label_multiple_old_alignment'],
+                  extensions=['png'])
+def test_bar_tick_label_multiple_old_alignment():
+    # From 2516: plot bar with array of string labels for x axis
+    matplotlib.rcParams["ytick.alignment"] = "center"
+    ax = plt.gca()
+    ax.bar([1, 2.5], [1, 2], width=[0.2, 0.5], tick_label=['a', 'b'],
+           align='center')
+
 
 @image_comparison(baseline_images=['barh_tick_label'],
                   extensions=['png'])
