import numpy as np
import pandas as pd
# data 출처: https://www.kaggle.com/hesh97/titanicdataset-traincsv/data
df = pd.read_csv('./train.csv')
df.head()
df.groupby('Pclass').mean()
df.groupby('Pclass').transform(np.mean)
df['Age2'] = df.groupby('Pclass').transform(np.mean)['Age']
df
df.groupby(['Pclass', 'Sex']).mean()
df['Age3'] = df.groupby(['Pclass', 'Sex']).transform(np.mean)['Age']
df