Transforming negative to positive values in dataframe - Python [duplicate]

Just use the built-in abs() function:

df_no_mv['Age_new'] = df_no_mv['Age'].abs()

This is just as per https://stackoverflow.com/a/29077254/1021819

REF: https://pandas.pydata.org/pandas-docs/dev/reference/api/pandas.DataFrame.abs.html

FWIW, python has abs() at the built-in level. numpy also has it.