[ARROW-1584] [PYTHON] serialize_pandas on empty dataframe

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 0.7.0
• Fix Version/s: 0.8.0
• Component/s: Python
• Labels: pull-request-available python serialization
• External issue URL: https://github.com/apache/arrow/issues/17597
• Assignee: Wes McKinney
• Reporter: Tom Augspurger
• Created: 20/Sep/17 21:59
• Updated: 11/Jan/23 07:15
• Resolved: 04/Oct/17 20:14

Description

This code

import pandas as pd
import pyarrow as pa

pa.serialize_pandas(pd.DataFrame())

Raises

---------------------------------------------------------------------------
ArrowNotImplementedError                  Traceback (most recent call last)
<ipython-input-71-ad21add45f0d> in <module>()
----> 1 pa.serialize_pandas(pd.DataFrame())

~/Envs/dask-dev/lib/python3.6/site-packages/pyarrow/ipc.py in serialize_pandas(df)
    158     sink = pa.BufferOutputStream()
    159     writer = pa.RecordBatchStreamWriter(sink, batch.schema)
--> 160     writer.write_batch(batch)
    161     writer.close()
    162     return sink.get_result()

pyarrow/ipc.pxi in pyarrow.lib._RecordBatchWriter.write_batch (/Users/travis/build/apache/arrow-dist/arrow/python/build/temp.macosx-10.6-intel-3.6/lib.cxx:59238)()

pyarrow/error.pxi in pyarrow.lib.check_status (/Users/travis/build/apache/arrow-dist/arrow/python/build/temp.macosx-10.6-intel-3.6/lib.cxx:8113)()

ArrowNotImplementedError: Unable to convert type: null

Presumably pa.deserialize_pandas will need a fix as well.

Issue Links

• links to: GitHub Pull Request #1155
• links to: GitHub Pull Request #1208