import numpy as np

import pandas as pd

df = pd.DataFrame(np.random.randint(0,100,100), columns=['score'])

# 以所在区间作为标签。如 x=5，返回：'[0-10]'

def make_label(x, step=10):

    m = x // step

    return '[{}-{}]'.format(m * step, (m+1) * step)

#df['level'] = df['score'].map(make_label)

df['level'] = df['score'].map(lambda x:make_label(x,step=10)) # 改变区间长度为15

res = df.groupby('level').size()

print(df.head())

print(res)