groupbyで複数の統計量

import pandas as pd
sample = pd.DataFrame(dict(
    x = [1,1,1],
    y = [1,2,3],
    z = [4,5,6]
))

sample.groupby(["x"]).agg({
    "y": ["mean", "sum", "max", "min", "median"],
    "z": ["mean", "sum", "max", "min", "median"]
})

参考