rebase onto upstream master

Author: anhqle

pandas/core/reshape/pivot.py

@@ -81,13 +81,6 @@ def pivot_table(data, values=None, index=None, columns=None, aggfunc='mean',
                 pass
         values = list(values)
 
-    num_rows = (data.reindex(columns=index).drop_duplicates().shape[0]
-                if index else 1)
-    num_cols = (data.reindex(columns=columns).drop_duplicates().shape[0]
-                if columns else 1)
-    if num_rows * num_cols * len(values) > (2 ** 31 - 1):
-        raise ValueError('Pivot table is too big, causing int32 overflow')
-
     grouped = data.groupby(keys)
     agged = grouped.agg(aggfunc)
     if dropna and isinstance(agged, ABCDataFrame) and len(agged.columns):

pandas/tests/reshape/test_pivot.py

@@ -1280,11 +1280,11 @@ def test_pivot_string_func_vs_func(self, f, f_numpy):
     def test_pivot_number_of_levels_larger_than_int32(self):
         # GH 20601
         df = DataFrame({'ind1': np.arange(2 ** 16),
-                          'ind2': np.arange(2 ** 16),
-                          'count': np.arange(2 ** 16)})
+                        'ind2': np.arange(2 ** 16),
+                        'count': np.arange(2 ** 16)})
         with tm.assert_raises_regex(ValueError, 'int32 overflow'):
             df.pivot_table(index='ind1', columns='ind2',
-                             values='count', aggfunc='count')
+                           values='count', aggfunc='count')
 
 
 class TestCrosstab(object):