Merge pull request #1579 from joferkington/fix-custom_projection_example

pelson · pelson · commit c13f6298cc86 · 2012-12-11T02:05:55.000-08:00
Updated custom_projection_example.py to work with v1.2 and newer
diff --git a/examples/api/custom_projection_example.py b/examples/api/custom_projection_example.py
@@ -1,5 +1,6 @@
 from __future__ import unicode_literals
 
+import matplotlib
 from matplotlib.axes import Axes
 from matplotlib.patches import Circle
 from matplotlib.path import Path
@@ -385,9 +386,10 @@ class HammerTransform(Transform):
         output_dims = 2
         is_separable = False
 
-        def transform(self, ll):
+        def transform_non_affine(self, ll):
             """
-            Override the transform method to implement the custom transform.
+            Override the transform_non_affine method to implement the custom 
+            transform.
 
             The input and output are Nx2 numpy arrays.
             """
@@ -411,10 +413,25 @@ def transform(self, ll):
         # differently-sized array, any transform that requires
         # changing the length of the data array must happen within
         # ``transform_path``.
-        def transform_path(self, path):
-            vertices = path.vertices
+        def transform_path_non_affine(self, path):
             ipath = path.interpolated(path._interpolation_steps)
             return Path(self.transform(ipath.vertices), ipath.codes)
+        transform_path_non_affine.__doc__ = \
+                Transform.transform_path_non_affine.__doc__
+
+        if matplotlib.__version__ < '1.2':
+            # Note: For compatibility with matplotlib v1.1 and older, you'll
+            # need to explicitly implement a ``transform`` method as well.
+            # Otherwise a ``NotImplementedError`` will be raised. This isn't
+            # necessary for v1.2 and newer, however.  
+            transform = transform_non_affine
+
+            # Similarly, we need to explicitly override ``transform_path`` if
+            # compatibility with older matplotlib versions is needed. With v1.2
+            # and newer, only overriding the ``transform_path_non_affine``
+            # method is sufficient.
+            transform_path = transform_path_non_affine
+            transform_path.__doc__ = Transform.transform_path.__doc__
 
         def inverted(self):
             return HammerAxes.InvertedHammerTransform()
@@ -425,7 +442,7 @@ class InvertedHammerTransform(Transform):
         output_dims = 2
         is_separable = False
 
-        def transform(self, xy):
+        def transform_non_affine(self, xy):
             x = xy[:, 0:1]
             y = xy[:, 1:2]
 
@@ -435,7 +452,12 @@ def transform(self, xy):
             longitude = 2 * np.arctan((z*x) / (2.0 * (2.0*z*z - 1.0)))
             latitude = np.arcsin(y*z)
             return np.concatenate((longitude, latitude), 1)
-        transform.__doc__ = Transform.transform.__doc__
+        transform_non_affine.__doc__ = Transform.transform_non_affine.__doc__
+
+        # As before, we need to implement the "transform" method for 
+        # compatibility with matplotlib v1.1 and older.
+        if matplotlib.__version__ < '1.2':
+            transform = transform_non_affine
 
         def inverted(self):
             # The inverse of the inverse is the original transform... ;)
