Filtering pandas dataframe with multiple Boolean columns

In [82]: d
Out[82]:
             A   B      C      D
0     John Doe  45   True  False
1   Jane Smith  32  False  False
2  Alan Holmes  55  False   True
3   Eric Lamar  29   True   True

Solution 1:

In [83]: d.loc[d.C | d.D]
Out[83]:
             A   B      C      D
0     John Doe  45   True  False
2  Alan Holmes  55  False   True
3   Eric Lamar  29   True   True

Solution 2:

In [94]: d[d[['C','D']].any(1)]
Out[94]:
             A   B      C      D
0     John Doe  45   True  False
2  Alan Holmes  55  False   True
3   Eric Lamar  29   True   True

Solution 3:

In [95]: d.query("C or D")
Out[95]:
             A   B      C      D
0     John Doe  45   True  False
2  Alan Holmes  55  False   True
3   Eric Lamar  29   True   True

PS If you change your solution to:

df[(df['C']==True) | (df['D']==True)]

it’ll work too

Pandas docs – boolean indexing


why we should NOT use “PEP complaint” df["col_name"] is True instead of df["col_name"] == True?

In [11]: df = pd.DataFrame({"col":[True, True, True]})

In [12]: df
Out[12]:
    col
0  True
1  True
2  True

In [13]: df["col"] is True
Out[13]: False               # <----- oops, that's not exactly what we wanted

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