[ARROW-4135] [Python] Can't reload a pandas dataframe containing a list of datetime.time

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.11.1
• Fix Version/s: 0.12.0
• Component/s: Python
• Labels: pull-request-available
• External issue URL: https://github.com/apache/arrow/issues/20722
• Assignee: Krisztian Szucs
• Reporter: Krisztian Szucs
• Created: 30/Dec/18 13:03
• Updated: 11/Jan/23 07:31
• Resolved: 31/Dec/18 16:44

Description

Ported from https://github.com/apache/arrow/issues/3223

This simple script writes a panda dataframe with a list of datetime.time. However, constructing back the pandas dataframe fails.

I initially realised that when doing a pd.read_parquet('example.parquet'), which fails with the same error.

This is using
pyarrow 0.11.1
pandas 0.23.4

import pandas as pd
import pyarrow as pa
import pyarrow.parquet as pq

times = pd.to_datetime(['09:00', '09:30', '10:00', '10:30', '11:00', '11:30', '12:00']).time
df = pd.DataFrame({'Time': [times]})

table = pa.Table.from_pandas(df)
pq.write_table(table, 'example.parquet')

# works
table2 = pq.read_table('example.parquet')

# fails: ArrowNotImplementedError: Not implemented type for list in DataFrameBlock: time64[us]
df2 = pa.Table.to_pandas(table2)

Issue Links

• links to: GitHub Pull Request #3289