Fixed a mistake with the Hammer projection in the geo module.

Thanks to Matthias Plum for reporting and Tobias Winchen for confirming.

svn path=/branches/v1_0_maint/; revision=8808

Author: WeatherGod

CHANGELOG

@@ -1,3 +1,5 @@
+2010-11-22 Fixed error with Hammer projection. - BVR
+
 2010-11-12 Fixed the placement and angle of axis labels in 3D plots. - BVR
 
 2010-11-07 New rc parameters examples.download and examples.directory

lib/matplotlib/projections/geo.py

@@ -346,7 +346,7 @@ def transform(self, ll):
             cos_latitude = np.cos(latitude)
             sqrt2 = np.sqrt(2.0)
 
-            alpha = 1.0 + cos_latitude * np.cos(half_long)
+            alpha = np.sqrt(1.0 + cos_latitude * np.cos(half_long))
             x = (2.0 * sqrt2) * (cos_latitude * np.sin(half_long)) / alpha
             y = (sqrt2 * np.sin(latitude)) / alpha
             return np.concatenate((x, y), 1)