使用熊猫使用另一列中的值填充特定列中的空白行

Question

If I have the following pandas dataframe

      A     B
0     Cat   Dog
1     Mouse Mouse
2     Fish  "Blank"

How do I parse through column B, identify that there is a blank value and then if there is a blank value fill in the blank with "Fish", so the desired data frame is:

      A     B
0     Cat   Dog
1     Mouse Mouse
2     Fish  Fish

Answer 1

You could try this -

import numpy as np
df['B'] = np.where(df['B'] == 'Blank', df['A'], df['B'])

Answer 2

• If only want to check from 'Blank' elements in column B:

df[df['B'] == 'Blank'] = 'Fish'

• Check to entire dataframe:

df[df=='Blank'] = 'Fish'