I would like to slice a DataFrame with a Boolean index obtaining a copy, and then do stuff on that copy independently of the original DataFrame.
Judging from this answer, selecting with .loc
using a Boolean array will hand me back a copy, but then, if I try to change the copy, SettingWithCopyWarning
gets in the way. Would this then be the correct way:
import numpy as np
import pandas as pd
d1 = pd.DataFrame(np.random.randn(10, 5), columns=['a', 'b', 'c', 'd', 'e'])
# create a new dataframe from the sliced copy
d2 = pd.DataFrame(d1.loc[d1.a > 1, :])
# do stuff with d2, keep d1 unchanged
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