rok commented on code in PR #34883:
URL: https://github.com/apache/arrow/pull/34883#discussion_r1159627221


##########
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:
   Right, but permutation would not roundtrip to numpy object and back. I'd 
prefer to throw NotImplemented if permutation is not trivial (C).



-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: [email protected]

For queries about this service, please contact Infrastructure at:
[email protected]

Reply via email to