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Mapping values of a DataFrame using a dictionary in Pandas
schedule Aug 10, 2023
Last updated local_offer
Tags Python●Pandas
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To map values of a DataFrame using a dictionary, use the DataFrame's replace(~) method.
Example
Consider the following DataFrame:
df = pd.DataFrame({"A":[1,2], "B":[3,4]})df
A B0 1 31 2 4
To replace all values of 1 and 3 with 5 and 6, respectively:
df.replace({1:5, 3:6})
A B0 5 61 2 4
Here, a new DataFrame is returned, and so the original df is kept intact. To directly modify df, set inplace=True.
To replace values in certain columns only:
df.replace({"A":1}, 5)
A B0 5 31 2 4
Here, we're only replacing the value 1 with 5 in column A.
Published by Isshin Inada
Edited by 0 others
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