Florian Jetter created ARROW-2646:
-------------------------------------
Summary: [Python] Pandas roundtrip for date objects
Key: ARROW-2646
URL: https://issues.apache.org/jira/browse/ARROW-2646
Project: Apache Arrow
Issue Type: Bug
Reporter: Florian Jetter
Arrow currently casts date objects to nanosecond precision datetime objects.
I'd like to have a way to preserve the type during a roundtrip
{code}
>>> import pandas as pd
>>> import pyarrow as pa
>>> import datetime
>>> pa.date32().to_pandas_dtype()
dtype('<M8[ns]')
>>> df = pd.DataFrame({'date': [datetime.date(2018, 1, 1)]})
>>> df.dtypes
date object
dtype: object
>>> df_rountrip = pa.Table.from_pandas(df).to_pandas()
>>> df_rountrip.dtypes
date datetime64[ns]
dtype: object
{code}
I'd expect something like this to work:
{code}
>>> import pandas.testing as pdt
>>> df_rountrip = pa.Table.from_pandas(df).to_pandas(date_as_object=True)
>>> pdt.assert_frame_equal(df_rountrip, df)
{code}
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
