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Reassigning column values in Pandas DataFrame
schedule Aug 12, 2023
Last updated local_offer
Tags Python●Pandas
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Reassigning entire column value
Consider the following DataFrame:
df = pd.DataFrame({"A":[3,4], "B":[5,6]})df
A B0 3 51 4 6
Using an array
To reassign the values of column B
:
df["B"] = [8,9]df
A B0 3 81 4 9
Using a constant
You could also assign a scalar to get a column of constants:
df["B"] = 7df
A B0 3 71 4 7
Replacing individual values
Consider the following DataFrame:
df = pd.DataFrame({"A":[3,4], "B":[5,6]})df
A B0 3 51 4 6
To replace individual values in a column, use the replace(~)
method like so:
df["B"].replace(5, 8, inplace=True)df
A B0 3 81 4 6
Here, inplace=True
means that we directly modify column B
instead of creating and returning a new column.
Published by Isshin Inada
Edited by 0 others
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