Pandas DataFrame - Replace NULL String with Blank and NULL Numeric with 0

Question

I am working on a large dataset with many columns of different types. There are a mix of numeric values and strings with some NULL values. I need to change the NULL Value to

Answer 1

You could try this to substitute a different value for each different column (A to C are numeric, while D is a string):

import pandas as pd
import numpy as np

df_pd = pd.DataFrame([[np.nan, 2, np.nan, '0'],
        [3, 4, np.nan, '1'],
        [np.nan, np.nan, np.nan, '5'],
        [np.nan, 3, np.nan, np.nan]],
        columns=list('ABCD'))

df_pd.fillna(value={'A':0.0,'B':0.0,'C':0.0,'D':''})