Examples
Whether each column contains at least one True element (the default).

In [1]:
import numpy as np
import pandas as pd
In [2]:
df = pd.DataFrame({"P": [2, 3], "Q": [0, 3], "R": [0, 0]})
df
Out[2]:
P Q R
0 2 0 0
1 3 3 0
In [3]:
df.any()
Out[3]:
P     True
Q     True
R    False
dtype: bool

Aggregating over the columns:

In [4]:
df = pd.DataFrame({"P": [True, False], "Q": [2, 3]})
df
Out[4]:
P Q
0 True 2
1 False 3
In [5]:
df.any(axis='columns')
Out[5]:
0    True
1    True
dtype: bool
In [6]:
df = pd.DataFrame({"P": [True, False], "Q": [2, 0]})
df
Out[6]:
P Q
0 True 2
1 False 0
In [7]:
df.any(axis='columns')
Out[7]:
0     True
1    False
dtype: bool

Aggregating over the entire DataFrame with axis=None:

In [8]:
df.any(axis=None)
Out[8]:
True
In [9]:
pd.DataFrame([]).any()
Out[9]:
Series([], dtype: bool)