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Flore W
4,744 PointsHow does fillna know which NaN values to replace?
users is a dataframe with different columns such as first_name, last_name, email, etc. Some of the last names are missing, and marked NaN.
The tutorial shows us how to fill those NaN with a string "Unknown".
The code looks like:
users_with_unknown = users.fillna('Unknown')
My question is does this line replace all values marked NaN (even in other columns than last_name) as "Unknown" ? In this case, how do I only replace the NaN in the last_name column with "Unknown"?
1 Answer
Wataru Ikarashi
15,824 PointsYou can use a dict to specify column(s).
users_with_unknown_a = users.fillna({'last_name': 'unknown'})