Multiindex Equals Not Commutative · Issue #46026 · pandas-dev/pandas (original) (raw)

Pandas version checks

Reproducible Example

import pandas as pd

df1 = pd.DataFrame({ 'a': [0, 0, 1, 1], 'b': [0, 1, 0, 1], 'c': [0, 0, 0, 0], 'v': [1, 2, 3, 4], }) df1['a'] = df1['a'].astype('Int32')

df2 = pd.DataFrame({ 'a': [0, 0, 1, 1], 'b': [0, 1, 0, 1], 'v': [1, 2, 3, 4], }) df2.set_index(['a', 'b'], inplace=True)

df1_agg = df1.groupby(['a', 'b']).agg({'v': 'max'})

print(df1_agg.index.equals(df2.index) == df2.index.equals(df1_agg.index))

Issue Description

For any 2 indexes, idx_1, idx_2, we should get the same result for idx_1.equals(idx_2) and idx_2.equals(idx_1). Currently they are not the same.

Expected Behavior

print(df1_agg.index.equals(df2.index) == df2.index.equals(df1_agg.index)) should print out True.

Installed Versions

INSTALLED VERSIONS

commit : bb1f651
python : 3.8.6.final.0
python-bits : 64
OS : Windows
OS-release : 10
Version : 10.0.19041
machine : AMD64
processor : Intel64 Family 6 Model 158 Stepping 13, GenuineIntel
byteorder : little
LC_ALL : None
LANG : None
LOCALE : English_United States.1252
pandas : 1.4.0
numpy : 1.19.0
pytz : 2021.3
dateutil : 2.8.1
pip : 21.3.1
setuptools : 49.2.1
Cython : None
pytest : 5.4.1
hypothesis : None
sphinx : None
blosc : None
feather : None
xlsxwriter : None
lxml.etree : None
html5lib : None
pymysql : None
psycopg2 : None
jinja2 : 3.0.3
IPython : None
pandas_datareader: None
bs4 : None
bottleneck : None
fastparquet : None
fsspec : 2021.10.0
gcsfs : None
matplotlib : None
numba : None
numexpr : None
odfpy : None
openpyxl : None
pandas_gbq : None
pyarrow : None
pyreadstat : None
pyxlsb : None
s3fs : None
scipy : 1.5.4
sqlalchemy : 1.4.31
tables : None
tabulate : None
xarray : None
xlrd : None
xlwt : None
zstandard : None