create new variable df python code example

Example: pandas mutate new column

#Using .assign you can make multiple
#operations that depend on the
#previous ones without the need
#of creating intermediate variables
import pandas as pd

df = pd.DataFrame({
    'name': ['alice','bob','charlie','daniel'],
    'age': [25,66,56,78]
})

df.assign(
    is_senior = lambda dataframe: dataframe['age'].map(lambda age: True if age >= 65 else False) 
).assign(
    name_uppercase = lambda dataframe: dataframe['name'].map(lambda name: name.upper()),
).assign(
    name_uppercase_double = lambda dataframe: dataframe['name_uppercase'].map(lambda name: name.upper()+"-"+name.upper())
)