python - 为什么 Pandas 会错误地评估一年中最后一天的周数？

Question

import pandas as pd    

t1 = pd.Timestamp('2018-01-01')
print(t1.week)

t364 = pd.Timestamp('2018-12-30')
print(t364.week)

t365 = pd.Timestamp('2018-12-31')
print(t365.week)

输出:

1
52
1

如果你依赖周数作为输入，它会严重破坏你的 count ifs、max ifs 等。

Answer 1

根据@zeeMonkeez 的评论，pandas 使用 ISO week date conventions .

解决方法是转换为 datetime，从年初提取天数，然后除以 7:

import pandas as pd
from math import ceil

def weeker(x):
    return ceil(x.to_pydatetime().timetuple().tm_yday / 7)

t1 = pd.Timestamp('2018-01-01')
print(t1.week, weeker(t1))  # 1 1

t364 = pd.Timestamp('2018-12-30')
print(t364.week, weeker(t364))  # 52 52

t365 = pd.Timestamp('2018-12-31')
print(t365.week, weeker(t365))  # 1 53