How to get the number of the most frequent value in a column?

Question

I have a data frame and I would like to know how many times a given column has the most frequent value.

I try to do it in the following way:

items_co         


        

Answer 1

You may also consider using scipy's mode function which ignores NaN. A solution using it could look like:

from scipy.stats import mode
from numpy import nan
df = DataFrame({"a": [1,2,2,4,2], "b": [nan, nan, nan, 3, 3]})
print mode(df)

The output would look like

(array([[ 2.,  3.]]), array([[ 3.,  2.]]))

meaning that the most common values are 2 for the first columns and 3 for the second, with frequencies 3 and 2 respectively.