How to count the NaN values in a column in pandas DataFrame

Question

I have data, in which I want to find number of NaN, so that if it is less than some threshold, I will drop this columns. I looked, but didn't able to find any function for this. There is value_counts, but it would be slow for me, because most of values are distinct and I want count of NaN only.

Answer 1

Hello @kartik,

Lets assume df is a pandas DataFrame.

Then,

df.isnull().sum(axis = 0)

This will give number of NaN values in every column.

If you need, NaN values in every row,

df.isnull().sum(axis = 1)

Hope this is helpful!!