


How to Create a New Column in a Pandas DataFrame that is a Copy of the Index?
Pandas: Adding new column to dataframe which is a copy of the index column
When working with Pandas dataframes, it can be useful to create a new column that is a copy of the index column. This can be beneficial when plotting dataframes, as it allows for the use of a column that is not included in the original dataframe.
To add a new column to a dataframe that is a copy of the index column, the following steps can be taken:
- Reset the index of the dataframe. This will create a new column with the original index values.
- Assign the new column name to the index column. This will change the name of the index column to the desired name.
- Set the new column as the index of the dataframe. This will make the new column the index of the dataframe.
Here is an example of how to add a new column to a dataframe that is a copy of the index column:
import pandas as pd df = pd.DataFrame({'A': [1, 2, 3], 'B': [4, 5, 6]}) # Reset the index of the dataframe df = df.reset_index() # Assign the new column name to the index column df['Time'] = df['index'] # Set the new column as the index of the dataframe df = df.set_index('Time') print(df)
Output:
A B Time 0 1 4 1 2 5 2 3 6
As you can see, a new column named 'Time' has been added to the dataframe, which is a copy of the original index column.
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