Fix positions of r axis labels when rmin != 0.0 in polar plots.

mdboom · mdboom · commit 3481e1014520 · 2010-08-18T17:00:29.000Z
svn path=/branches/v1_0_maint/; revision=8649
diff --git a/lib/matplotlib/projections/polar.py b/lib/matplotlib/projections/polar.py
@@ -14,7 +14,7 @@
 from matplotlib.ticker import Formatter, Locator, FormatStrFormatter
 from matplotlib.transforms import Affine2D, Affine2DBase, Bbox, \
     BboxTransformTo, IdentityTransform, Transform, TransformWrapper, \
-    ScaledTranslation, blended_transform_factory
+    ScaledTranslation, blended_transform_factory, BboxTransformToMaxOnly
 import matplotlib.spines as mspines
 
 class PolarAxes(Axes):
@@ -41,16 +41,16 @@ def __init__(self, axis=None):
             self._axis = axis
 
         def transform(self, tr):
-            xy   = np.zeros(tr.shape, np.float_)
+            xy = np.empty(tr.shape, np.float_)
             if self._axis is not None:
                 rmin = self._axis.viewLim.ymin
             else:
                 rmin = 0
 
-            t    = tr[:, 0:1]
-            r    = tr[:, 1:2]
-            x    = xy[:, 0:1]
-            y    = xy[:, 1:2]
+            t = tr[:, 0:1]
+            r = tr[:, 1:2]
+            x = xy[:, 0:1]
+            y = xy[:, 1:2]
 
             if rmin != 0:
                 r = r - rmin
@@ -188,7 +188,7 @@ def refresh(self):
 
         def view_limits(self, vmin, vmax):
             vmin, vmax = self.base.view_limits(vmin, vmax)
-            return 0, vmax
+            return vmin, vmax
 
 
     def __init__(self, *args, **kwargs):
@@ -290,15 +290,17 @@ def _set_lim_and_transforms(self):
         # The r-axis labels are put at an angle and padded in the r-direction
         self._r_label1_position = ScaledTranslation(
             22.5, self._rpad,
-            blended_transform_factory(Affine2D(), BboxTransformTo(self.viewLim)))
+            blended_transform_factory(
+                Affine2D(), BboxTransformToMaxOnly(self.viewLim)))
         self._yaxis_text1_transform = (
             self._r_label1_position +
             Affine2D().scale(1.0 / 360.0, 1.0) +
             self._yaxis_transform
             )
         self._r_label2_position = ScaledTranslation(
             22.5, -self._rpad,
-            blended_transform_factory(Affine2D(), BboxTransformTo(self.viewLim)))
+            blended_transform_factory(
+                Affine2D(), BboxTransformToMaxOnly(self.viewLim)))
         self._yaxis_text2_transform = (
             self._r_label2_position +
             Affine2D().scale(1.0 / 360.0, 1.0) +
diff --git a/lib/matplotlib/transforms.py b/lib/matplotlib/transforms.py
@@ -2107,6 +2107,31 @@ def get_matrix(self):
     get_matrix.__doc__ = Affine2DBase.get_matrix.__doc__
 
 
+class BboxTransformToMaxOnly(BboxTransformTo):
+    """
+    :class:`BboxTransformTo` is a transformation that linearly
+    transforms points from the unit bounding box to a given
+    :class:`Bbox` with a fixed upper left of (0, 0).
+    """
+    def __repr__(self):
+        return "BboxTransformToMaxOnly(%s)" % (self._boxout)
+    __str__ = __repr__
+
+    def get_matrix(self):
+        if self._invalid:
+            xmax, ymax = self._boxout.max
+            if DEBUG and (xmax == 0 or ymax == 0):
+                raise ValueError("Transforming to a singular bounding box.")
+            self._mtx = np.array([[xmax,  0.0, 0.0],
+                                  [ 0.0, ymax, 0.0],
+                                  [ 0.0,  0.0, 1.0]],
+                                 np.float_)
+            self._inverted = None
+            self._invalid = 0
+        return self._mtx
+    get_matrix.__doc__ = Affine2DBase.get_matrix.__doc__
+
+
 class BboxTransformFrom(Affine2DBase):
     """
     :class:`BboxTransformFrom` linearly transforms points from a given
