rok commented on code in PR #34883:
URL: https://github.com/apache/arrow/pull/34883#discussion_r1162142218


##########
python/pyarrow/array.pxi:
##########
@@ -3076,6 +3076,111 @@ cdef class ExtensionArray(Array):
         return Array._to_pandas(self.storage, options, **kwargs)
 
 
+class FixedShapeTensorArray(ExtensionArray):
+    """
+    Concrete class for fixed shape tensor extension arrays.
+
+    Examples
+    --------
+    Define the extension type for tensor array
+
+    >>> import pyarrow as pa
+    >>> tensor_type = pa.fixed_shape_tensor(pa.int32(), [2, 2])
+
+    Create an extension array
+
+    >>> arr = [[1, 2, 3, 4], [10, 20, 30, 40], [100, 200, 300, 400]]
+    >>> storage = pa.array(arr, pa.list_(pa.int32(), 4))
+    >>> pa.ExtensionArray.from_storage(tensor_type, storage)
+    <pyarrow.lib.FixedShapeTensorArray object at ...>
+    [
+      [
+        1,
+        2,
+        3,
+        4
+      ],
+      [
+        10,
+        20,
+        30,
+        40
+      ],
+      [
+        100,
+        200,
+        300,
+        400
+      ]
+    ]
+    """
+
+    def to_numpy_ndarray(self):
+        """
+        Convert fixed shape tensor extension array to a numpy array (with 
dim+1).
+        """
+        np_flat = np.asarray(self.storage.values)
+        numpy_tensor = np_flat.reshape((len(self),) + tuple(self.type.shape),
+                                       order='C')

Review Comment:
   > 2. `to_numpy_ndarray` is reshaping 1-D array so there is no need to check 
the layout style as 1-D array is always both C-contiguous and F-contiguous.
   
   While that's true for the physical layout it's not necessarily true for the 
logical layout. I propose 
(https://github.com/apache/arrow/pull/34883#pullrequestreview-1378208716) we 
block converting tensors with non-trivial permutations and add correct logic to 
handle those later. (Another option is to go via `array.ToTensor().to_numpy()` 
once [`FromTensor/ToTensor`](https://github.com/apache/arrow/pull/34797) is 
merged.)



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