7

Given a day, I want to get all days(datetime instances) of the week in which day is present.

I have a solution, please correct me if there is something wrong of if more efficient method exists.

>>> import datetime
>>> today = datetime.datetime(2013, 06, 26)
>>> today
datetime.datetime(2013, 6, 26, 0, 0)
>>> day_of_week = today.isocalendar()[2] - 1
>>> day_of_week
2
>>> start_date = today - timedelta(days=day_of_week)
>>> start_date
datetime.datetime(2013, 6, 24, 0, 0) # Got monday
>>> dates = [start + timedelta(days=i) for i in range(7)]
>>> dates
[datetime.datetime(2013, 6, 24, 0, 0),
 datetime.datetime(2013, 6, 25, 0, 0),
 datetime.datetime(2013, 6, 26, 0, 0),
 datetime.datetime(2013, 6, 27, 0, 0),
 datetime.datetime(2013, 6, 28, 0, 0),
 datetime.datetime(2013, 6, 29, 0, 0),
 datetime.datetime(2013, 6, 30, 0, 0)]

I want monday to be start date and sunday the end date.

Martijn Pieters
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rajpy
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1 Answers1

17

I'd use datetime.date() instead to make it clear we are calculating dates here, and use date.weekday() to get the current weekday instead of using the .isocalendar() call, giving us a 0-based weekday number (0 is Monday). 

import datetime

today = datetime.date(2013, 06, 26)
dates = [today + datetime.timedelta(days=i) for i in range(0 - today.weekday(), 7 - today.weekday())]

Demo:

>>> from pprint import pprint
>>> import datetime
>>> today = datetime.date(2013, 06, 26)
>>> pprint([today + datetime.timedelta(days=i) for i in range(0 - today.weekday(), 7 - today.weekday())])
[datetime.date(2013, 6, 24),
 datetime.date(2013, 6, 25),
 datetime.date(2013, 6, 26),
 datetime.date(2013, 6, 27),
 datetime.date(2013, 6, 28),
 datetime.date(2013, 6, 29),
 datetime.date(2013, 6, 30)]

On python 2 you can replace range() with xrange() if you like; for a 7-day value that won't make much difference.

Just to make it explicit; datetime.weekday() exists as well, and there is a .isoweekday() too, so there is no need to use .isocalendar() anywhere.

Martijn Pieters
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  • @MartjinPieters: Thanks for tips. I was looking at this question: http://stackoverflow.com/questions/2003841/how-can-i-get-the-current-week-using-python. It was looking complicated.I thought my method is easy, but was skeptical about it. Thanks again. – rajpy Jun 24 '13 at 14:07
  • The answer there uses `.weekday()` as well; the `.isocalendar()` call is merely used to get the week number. – Martijn Pieters Jun 24 '13 at 14:08