update

Signed-off-by: You-Cheng Lin <mses010108@gmail.com>

Author: owenowenisme

python/ray/air/util/tensor_extensions/pandas.py

@@ -949,12 +949,8 @@ def isna(self) -> "TensorArray":
             return np.array(
                 [self._tensor[i] is None for i in range(len(self))], dtype=bool
             )
-        elif self._tensor.dtype.type is np.str_:
-            return np.all(self._tensor == "", axis=tuple(range(1, self._tensor.ndim)))
         else:
-            return np.all(
-                np.isnan(self._tensor), axis=tuple(range(1, self._tensor.ndim))
-            )
+            return np.zeros(len(self), dtype=bool)
 
     def take(
         self, indices: Sequence[int], allow_fill: bool = False, fill_value: Any = None