which columns have null values in pandas code example

Example 1: find nan values in a column pandas

df['your column name'].isnull().values.any()

Example 2: find nan values in a column pandas

df.isnull().sum().sum()

Example 3: show which columns in dataframe have NA

In [71]: df
Out[71]:
     a    b  c
0  NaN  7.0  0
1  0.0  NaN  4
2  2.0  NaN  4
3  1.0  7.0  0
4  1.0  3.0  9
5  7.0  4.0  9
6  2.0  6.0  9
7  9.0  6.0  4
8  3.0  0.0  9
9  9.0  0.0  1

In [72]: df.isna().any()
Out[72]:
a     True
b     True
c    False
dtype: bool