On Wed, Jan 6, 2021 at 10:01 AM Eli the Bearded <*@eli.users.panix.com> wrote: > > In comp.lang.python, Chris Angelico <ros...@gmail.com> wrote: > > There are multiple definitions for "day of year", depending on how you > > want to handle certain oddities. The simplest is to identify Jan 1st > > as 1, Jan 2nd as 2, etc, to Dec 31st as either 365 or 366; but some > > libraries will define the year as starting with the week that contains > > the Thursday, or something, and then will define days of year > > accordingly. > > That sounds like some weird off-shoot of the ISO-8601 calendar. That > document primarily concerns itself with weeks. Week 1 of a year is the > first week with a Thursday in it. The last week of a year will be either > 52 or 53, and you can have things like days in January belonging to the > week of the previous year.
The "weird off-shoot" part is probably a result of me misremembering things, so don't read too much into the details :) I just remember coming across something that numbered days within a year in a way that was consistent with the way that it numbered weeks, which would indeed have been based on the ISO 8601 week numbering. Not 100% sure of the exact details. ChrisA -- https://mail.python.org/mailman/listinfo/python-list