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REGR: DataFrame.eval not respecting inplace argument in pandas 1.4

See original GitHub issue

import pandas as pd
import numpy as np

# Example for eval
pdf = pd.DataFrame({"A": range(1, 6), "B": range(10, 0, -2), "C": range(11, 16)})
pser = pdf.A
pdf.eval("A = B + C", inplace=True)
# pser != pdf.A after 1.4

_Originally posted by @Yikun in https://github.com/pandas-dev/pandas/issues/47188#issuecomment-1148168713_

Issue Analytics

State:
Created a year ago
Reactions:2
Comments:7 (7 by maintainers)

Top GitHub Comments

1reaction

jorisvandenbosschecommented, Aug 12, 2022

@Yikun we are fixing this in https://github.com/pandas-dev/pandas/pull/47550, but in general I would recommend to not rely on this too much (updating Series by performing inplace on the DataFrame). There are plans to change that behaviour (https://github.com/pandas-dev/pandas/issues/36195), and actually also to deprecate the inplace keyword (https://github.com/pandas-dev/pandas/issues/16529)

0reactions

Yikuncommented, Aug 12, 2022

@jorisvandenbossche Thanks for your info!

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