Filling a DataFrame with “sign” numbers

Question

I have a DataFrame full of floats (positive and negative) and some NaN. I\'d like to replace every single float number with its sign:

if it\'s NaN -> it remai         


        

Answer 1

Code -

import pandas as pd


df = pd.DataFrame({'x' : [-5.3, 2.5, 0, float('nan')]})

df['x'] = df['x'].apply(func = lambda x : x if not x else x // abs(x))

print(df)

Output -

    x
0  -1
1   1
2   0
3 NaN