如何根据开始和结束获取for循环中的日期列表？

Question

我想使用 for 循环获取开始日期和结束日期之间范围的唯一 yyyy-mm-01 列表。这是我的代码：import datetimefrom datetime import timedelta, datestart=date(2017,4,1)end=(datetime.date.today().replace(day=1)) - datetime.timedelta(days=1) #last completed monthdef daterange(start, end):    for n in range(int((end - start).days)):        yield start + timedelta(n)for single_date in daterange(start, end):    myset = str(single_date.strftime("%Y-%m-01"))    print(myset)The issue is that my result looks like this:2017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-04-012017-05-01我尝试添加 set() 但它仍然显示冗余日期。我该如何解决？

Answer 1

dates = set()

for single_date in daterange(start, end):

    dates.add(single_date.strftime("%Y-%m-01"))

print(sorted(list(dates)))

Answer 2

import datetime

from datetime import timedelta, date

from dateutil.relativedelta import relativedelta

start=date(2017,4,1)

end=(datetime.date.today().replace(day=1)) - datetime.timedelta(days=1) #last completed month

lst = []

current_date = start

while current_date < end:

    current_date = current_date.replace(day=1) + relativedelta(months=1)

    lst.append(current_date)

print(lst)

Answer 3

问题是你实际上并没有使用你的集合来检查你之前是否见过一个日期：

myset = set()

for single_date in daterange(start, end):

    mydate = str(single_date.strftime("%Y-%m-01"))

    if mydate not in myset:

        print(mydate)

        myset.add(mydate)

Answer 4

我强烈建议您使用dateutils模块来获取这样的重复日期。您可以使用cmd安装它pip install python-dateutil

>>> from dateutil.rrule import rrule, MONTHLY

>>>

>>> start=date(2017,4,1)

>>> end=(datetime.date.today().replace(day=1)) - datetime.timedelta(days=1)

>>> res = list(d.strftime("%Y-%m-%d") for d in rrule(dtstart=start, until=end, freq=MONTHLY))

>>> pprint(res)

['2017-04-01',

 '2017-05-01',

 '2017-06-01',

 '2017-07-01',

 '2017-08-01',

 '2017-09-01',

 '2017-10-01',

 '2017-11-01',

 '2017-12-01',

 '2018-01-01',

 '2018-02-01',

 '2018-03-01',

 '2018-04-01',

 '2018-05-01',

 '2018-06-01',

 '2018-07-01',

 '2018-08-01',

 '2018-09-01',

 '2018-10-01',

 '2018-11-01',

 '2018-12-01',

 '2019-01-01',

 '2019-02-01',

 '2019-03-01',

 '2019-04-01',

 '2019-05-01',

 '2019-06-01',

 '2019-07-01',

 '2019-08-01',

 '2019-09-01',

 '2019-10-01',

 '2019-11-01',

 '2019-12-01',

 '2020-01-01',

 '2020-02-01',

 '2020-03-01',

 '2020-04-01',

 '2020-05-01',

 '2020-06-01',

 '2020-07-01']