Replace column names / values with pandas dataframe

Contents

It is an operation to replace the column name and record value of the data frame created by pandas. For column names, use the rename method. Use the replace method for the record value.

Advance preparation

The environment used jupyter notebook. First, create a data frame.

python


import pandas as pd

df = pd.DataFrame({"fruits":("Mandarin orange", "Apple","Grape"),"Origin":("Ehime","Aomori","Yamanashi")})

df.head()
fruits Origin
0 Mandarin orange Ehime
1 Apple Aomori
2 Grape Yamanashi

Rename column

Pass columns as the argument of the rename method. The same data frame is preserved by setting inplace = True.

df.rename(columns = {"fruits":"Fruits"}, inplace = True)
df.head()
Fruits Origin
0 Mandarin orange Ehime
1 Apple Aomori
2 Grape Yamanashi

Change record value

Use the replace method.

df["Fruits"].replace("Mandarin orange", "Orange", inplace = True)
df.head()
Fruits Origin
0 Orange Ehime
1 Apple Aomori
2 Grape Yamanashi

You can also replace multiple values at once.

df["Origin"].replace({"Ehime":"Ehime", "Aomori":"Aomori", "Yamanashi":"Yamanashi"}, inplace = True)
df.head()
Fruits Origin
0 Orange Ehime
1 Apple Aomori
2 Grape Yamanashi

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