python - 将天数 Int64 转换为日期

Question

我需要将以下数据框(天)转换为实际日期。当 (days=0) 这是基准年 01/01/1960。您能否协助将天数列(从 1960 年 1 月 1 日开始的天数)转换回日期？

df=pd.DataFrame([-730,-640,-549,457,-365,275,-184,-92,0,91,182,274,366],columns=['days'])
df['base_year']=datetime.date(1960,1,1)

Answer 1

回过头来看，MaxU的回答更好。以下内容可能对旧版 Pandas 有用。

有几种方法可以做到这一点。一种是将 datetime.timedelta 与列表理解一起使用:

from datetime import timedelta
import pandas as pd

>>> [pd.to_datetime('01/01/1960') + timedelta(d) for d in [-730,-640,-549,457,-365,275,-184,-92,0,91,182,274,366]]
[Timestamp('1958-01-01 00:00:00'),
 Timestamp('1958-04-01 00:00:00'),
 Timestamp('1958-07-01 00:00:00'),
 Timestamp('1961-04-02 00:00:00'),
 Timestamp('1959-01-01 00:00:00'),
 Timestamp('1960-10-02 00:00:00'),
 Timestamp('1959-07-01 00:00:00'),
 Timestamp('1959-10-01 00:00:00'),
 Timestamp('1960-01-01 00:00:00'),
 Timestamp('1960-04-01 00:00:00'),
 Timestamp('1960-07-01 00:00:00'),
 Timestamp('1960-10-01 00:00:00'),
 Timestamp('1961-01-01 00:00:00')]

所以你可以使用

>>> DataFrame([pd.to_datetime('01/01/1960') + timedelta(d) for d in [-730,-640,-549,457,-365,275,-184,-92,0,91,182,274,366]],columns=['days'])
    days
0   1958-01-01
1   1958-04-01
2   1958-07-01
3   1961-04-02
4   1959-01-01
5   1960-10-02
6   1959-07-01
7   1959-10-01
8   1960-01-01
9   1960-04-01
10  1960-07-01
11  1960-10-01
12  1961-01-01