Fix passing shape (2,) input to Collections.set_offsets.

anntzer · anntzer · commit 9ccda79a3dcb · 2017-09-26T14:49:08.000-07:00
The logic with uniform_offsets seems a bit crazy but let's just
reproduce it for now...
diff --git a/lib/matplotlib/collections.py b/lib/matplotlib/collections.py
@@ -143,15 +143,15 @@ def __init__(self,
         self.set_offset_position(offset_position)
         self.set_zorder(zorder)
 
+        self._offsets = np.zeros((1, 2))
         self._uniform_offsets = None
-        self._offsets = np.array([[0, 0]], float)
         if offsets is not None:
-            offsets = np.asanyarray(offsets, float)
             if transOffset is not None:
-                self._offsets = offsets
                 self._transOffset = transOffset
             else:
-                self._uniform_offsets = offsets
+                # Just a placeholder to trigger the right path in set_offsets.
+                self._uniform_offsets = object()
+            self.set_offsets(offsets)
 
         self._path_effects = None
         self.update(kwargs)
@@ -400,7 +400,7 @@ def set_hatch(self, hatch):
         self.stale = True
 
     def get_hatch(self):
-        'Return the current hatching pattern'
+        """Return the current hatching pattern."""
         return self._hatch
 
     def set_offsets(self, offsets):
@@ -411,18 +411,18 @@ def set_offsets(self, offsets):
         ACCEPTS: float or sequence of floats
         """
         offsets = np.asanyarray(offsets, float)
-        #This decision is based on how they are initialized above
+        if offsets.shape == (2,):  # Broadcast (2,) -> (1, 2) but nothing else.
+            offsets = offsets[None, :]
+        # This decision is based on how they are initialized above in __init__.
         if self._uniform_offsets is None:
             self._offsets = offsets
         else:
             self._uniform_offsets = offsets
         self.stale = True
 
     def get_offsets(self):
-        """
-        Return the offsets for the collection.
-        """
-        #This decision is based on how they are initialized above in __init__()
+        """Return the offsets for the collection."""
+        # This decision is based on how they are initialized above in __init__.
         if self._uniform_offsets is None:
             return self._offsets
         else:
