BUG: Adjust cond shape to SparseBlock

SparseDataFrame.where passes n-length SparseBlock and (1, n)-shape condition block to Block.where.

Author: Licht-T

pandas/core/internals.py

@@ -1405,6 +1405,9 @@ def where(self, other, cond, align=True, raise_on_error=True,
         if not hasattr(cond, 'shape'):
             raise ValueError("where must have a condition that is ndarray "
                              "like")
+        else:
+            if self.is_sparse:
+                cond = cond.flatten()
 
         # our where function
         def func(cond, values, other):