Joris Van den Bossche created ARROW-8442: --------------------------------------------
Summary: [Python] NullType.to_pandas_dtype inconsisent with dtype returned in to_pandas/to_numpy Key: ARROW-8442 URL: https://issues.apache.org/jira/browse/ARROW-8442 Project: Apache Arrow Issue Type: Bug Components: Python Reporter: Joris Van den Bossche There is this behaviour of {{to_pandas_dtype}} returning float, while all actual conversions to numpy or pandas use object dtype: {code} In [23]: pa.null().to_pandas_dtype() Out[23]: numpy.float64 In [24]: pa.array([], pa.null()).to_pandas() Out[24]: Series([], dtype: object) In [25]: pa.array([], pa.null()).to_numpy(zero_copy_only=False) Out[25]: array([], dtype=object) {code} So we should probably fix {{NullType.to_pandas_dtype}} to return object, which is used in practice. -- This message was sent by Atlassian Jira (v8.3.4#803005)