Tim Peters added the comment: Well, a timedelta is a duration. timedelta // n is as close as possible to one n'th of that duration, but "rounding down" (if necessary) so that the result is representable as a timedelta. In the same way, if i and j are integers, i // j is as close as possible to one j'th of i, but "rounding down" (if necessary) so that the result is representable as an integer. Like:
>>> from datetime import timedelta >>> timedelta(1) // 7 datetime.timedelta(0, 12342, 857142) >>> timedelta(1) - 7 * _ datetime.timedelta(0, 0, 6) >>> The last line shows the part truncated away: one seventh of a day is not representable as a timedetla. If `timedelta // int` rounded to the closest representable timedelta, it would return timedelta(0, 12342, 857143) instead. That's a little bigger than a seventh of a day: >>> timedelta(0, 12342, 857143) * 7 datetime.timedelta(1, 0, 1) It has nothing directly to do with days, hours, seconds ... it so happens that timedelta has microsecond resolution, so the closest representable approximations to one n'th of a timedelta most often have non-zero microsecond components. If timedelta had femtosecond resolution, they'd most often have non-zero femtosecond components ;-) ---------- nosy: +tim_one _______________________________________ Python tracker <rep...@bugs.python.org> <http://bugs.python.org/issue18629> _______________________________________ _______________________________________________ Python-bugs-list mailing list Unsubscribe: http://mail.python.org/mailman/options/python-bugs-list/archive%40mail-archive.com
