从结构不均匀的字符串中提取日期

Question

我正在尝试从字符串中提取日期信息.字符串可能如下所示:

1. 5个月零17个小时
2. 1个月和19天
3. 3个月零1天
4. 2年1个月和2天
5. 1年1个月,1天1小时

我想提取:

1. y = 0 m = 5 d = 0 h = 17
2. y = 0 m = 1 d = 19 h = 0
3. y = 0 m = 3 d = 1 h = 0
4. y = 2 m = 1 d = 2 h = 0
5. y = 1 m = 1 d = 1 h = 1

我开始做这样的事情:

publishedWhen = '1 year 1 month and 1 days and 1 hour'

y,m,d,h = 0,0,0,0

if 'day ' in publishedWhen:
    d = int(publishedWhen.split(' day ')[0])

if 'days ' in publishedWhen:
    d = int(publishedWhen.split(' days ')[0])

if 'days ' not in publishedWhen and 'day ' not in publishedWhen:
    d = 0

if 'month ' in publishedWhen:
    m = int(publishedWhen.split(' month ')[0])
    d = int(publishedWhen.replace(publishedWhen.split(' month ')[0] + ' month ','').replace('and','').replace('days','').replace('day',''))

if 'months ' in publishedWhen:
    m = int(publishedWhen.split(' months ')[0])

但是,我知道这个代码是错误的(有些情况可能没有考虑到),正则表达式可能会产生更清洁和有效的东西.这是真的？哪个正则表达式可以帮助我提取所有这些信息？

Answer 1

您不必使用re\gular expres {2}离子？而是在Python Package Index中查看非常丰富的第三方软件包库.

例如,您可以使用dateparser- 用于解析人类可读日期和dateutil- 用于相对delta对象的组合:

from datetime import datetime

import dateparser as dateparser
from dateutil.relativedelta import relativedelta


BASE_DATE = datetime(2018, 1, 1)


def get_relative_date(date_string):
    parsed_date = dateparser.parse(date_string, settings={"RELATIVE_BASE": BASE_DATE})
    return relativedelta(parsed_date, BASE_DATE)


date_strings = [
    "5 months and 17 hours",
    "1 month and 19 days",
    "3 months and 1 day",
    "2 years 1 month and 2 days",
    "1 year 1 month and 1 days and 1 hour"
]

for date_string in date_strings:
    delta = get_relative_date(date_string)
    print(f"y={abs(delta.years)} m={abs(delta.months)} d={abs(delta.days)} h={abs(delta.hours)}")

打印:

y=0 m=5 d=0 h=17
y=0 m=1 d=19 h=0
y=0 m=3 d=1 h=0
y=2 m=1 d=2 h=0
y=1 m=1 d=1 h=1

我并不特别喜欢需要使用某个基准日期来执行delta,并且非常确定有一个可以直接解析为delta对象的包.对任何建议开放.