BUG: pyarrow listaccessor does not preserve indexes · Issue #58425 · pandas-dev/pandas (original) (raw)

Pandas version checks

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Reproducible Example

import pandas as pd from pandas import ArrowDtype import pyarrow as pa

pd.options.mode.string_storage = "pyarrow" og_df = df df = pd.DataFrame(dict(v=['a', 'b']), index=[1, 3]) df['v'] = df['v'].astype(ArrowDtype(pa.string())) ser = df['v'].str.split('-') accessed = ser.list[0] print('comparing indexes:') print('original:') print(df.index) print('after list accessor:') print(accessed.index)

print('misc:') print(df.dtypes) print('----') print(ser.dtype) print('----') print(accessed.dtype)

Issue Description

after using pyarrow's listaccessor's methods on a pandas series the returned series always has a RangeIndex index regardless of the original series's index.

Expected Behavior

I would have expected the indices to be identical.

Installed Versions

INSTALLED VERSIONS

commit : bdc79c1
python : 3.11.4.final.0
python-bits : 64
OS : Darwin
OS-release : 23.4.0
Version : Darwin Kernel Version 23.4.0: Fri Mar 15 00:11:05 PDT 2024; root:xnu-10063.101.17~1/RELEASE_X86_64
machine : x86_64
processor : i386
byteorder : little
LC_ALL : None
LANG : None
LOCALE : None.UTF-8

pandas : 2.2.1
numpy : 1.26.4
pytz : 2024.1
dateutil : 2.9.0.post0
setuptools : 69.1.1
pip : 23.2.1
Cython : None
pytest : None
hypothesis : None
sphinx : None
blosc : None
feather : None
xlsxwriter : None
lxml.etree : 5.1.0
html5lib : None
pymysql : 1.4.6
psycopg2 : None
jinja2 : 3.1.3
IPython : 8.23.0
pandas_datareader : None
adbc-driver-postgresql: None
adbc-driver-sqlite : None
bs4 : 4.12.3
bottleneck : None
dataframe-api-compat : None
fastparquet : 2024.2.0
fsspec : 2024.2.0
gcsfs : None
matplotlib : 3.8.3
numba : 0.59.0
numexpr : None
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : 15.0.0
pyreadstat : None
python-calamine : None
pyxlsb : None
s3fs : 2024.2.0
scipy : 1.12.0
sqlalchemy : 2.0.27
tables : None
tabulate : 0.9.0
xarray : None
xlrd : None
zstandard : None
tzdata : 2024.1
qtpy : None
pyqt5 : None