BUG: Fixed GH 16179 in a more elegant manner

Author: kristopheryahoo

pandas/core/sparse/frame.py

@@ -190,14 +190,12 @@ def _init_spmatrix(self, data, index, columns, dtype=None,
         values = Series(data.data, index=data.row, copy=False)
         for col, rowvals in values.groupby(data.col):
             # get_blocks expects int32 row indices in sorted order
+            rowvals.sort_index(inplace=True)
             rows = rowvals.index.values.astype(np.int32)
-            vals = np.array([y for x, y in sorted(rowvals.iteritems())],
-                            dtype=rowvals.dtype)
-            rows.sort()
             blocs, blens = get_blocks(rows)
 
             sdict[columns[col]] = SparseSeries(
-                vals, index=index,
+                rowvals.values, index=index,
                 fill_value=fill_value,
                 sparse_index=BlockIndex(N, blocs, blens))