Cache tick space calculation

mdboom · mdboom · commit 63c9b43f38bc · 2015-12-10T13:31:27.000-05:00
diff --git a/lib/matplotlib/axis.py b/lib/matplotlib/axis.py
@@ -654,6 +654,7 @@ def __init__(self, axes, pickradius=15):
         # Initialize here for testing; later add API
         self._major_tick_kw = dict()
         self._minor_tick_kw = dict()
+        self._tick_space = None
 
         self.cla()
         self._set_scale('linear')
@@ -785,6 +786,7 @@ def set_tick_params(self, which='major', reset=False, **kw):
                 for tick in self.minorTicks:
                     tick._apply_params(**self._minor_tick_kw)
         self.stale = True
+        self._tick_space = None
 
     @staticmethod
     def _translate_tick_kw(kw, to_init_kw=True):
@@ -2339,11 +2341,12 @@ def set_default_intervals(self):
         self.stale = True
 
     def get_tick_space(self):
-        # TODO: cache this computation
-        ends = self.axes.transAxes.transform([[0, 0], [0, 1]])
-        length = ((ends[1][1] - ends[0][1]) / self.axes.figure.dpi) * 72.0
-        tick = self._get_tick(True)
-        # Having a spacing of at least 2 just looks good.
-        size = tick.label1.get_size() * 2.0
-        size *= np.cos(np.deg2rad(tick.label1.get_rotation()))
-        return np.floor(length / size)
+        if self._tick_space is None:
+            ends = self.axes.transAxes.transform([[0, 0], [0, 1]])
+            length = ((ends[1][1] - ends[0][1]) / self.axes.figure.dpi) * 72.0
+            tick = self._get_tick(True)
+            # Having a spacing of at least 2 just looks good.
+            size = tick.label1.get_size() * 2.0
+            size *= np.cos(np.deg2rad(tick.label1.get_rotation()))
+            self._tick_space = np.floor(length / size)
+        return self._tick_space
