FIX-#3725: do not trigger computation of lazy 'dtypes' on transpose (#…

…3748) Signed-off-by: Dmitry Chigarev <dmitry.chigarev@intel.com>
modin-project · Dec 3, 2021 · cd8db0c · cd8db0c
1 parent e9c06f2
commit cd8db0c
Showing 1 changed file with 7 additions and 4 deletions.
diff --git a/modin/core/dataframe/pandas/dataframe/dataframe.py b/modin/core/dataframe/pandas/dataframe/dataframe.py
@@ -2300,10 +2300,13 @@ def transpose(self):
         new_partitions = self._partition_mgr_cls.lazy_map_partitions(
             self._partitions, lambda df: df.T
         ).T
-        new_dtypes = pandas.Series(
-            np.full(len(self.index), find_common_type(self.dtypes.values)),
-            index=self.index,
-        )
+        if self._dtypes is not None:
+            new_dtypes = pandas.Series(
+                np.full(len(self.index), find_common_type(self.dtypes.values)),
+                index=self.index,
+            )
+        else:
+            new_dtypes = None
         return self.__constructor__(
             new_partitions,
             self.columns,