week_of_year()

Returns an integer which represents the week number. The week number is calculated from the first week of a year, which is the one that includes the first Thursday, according to ISO 8601.

week_of_year(datetime("2015-12-14"))

Syntax

week_of_year(a_date)

Arguments

  • a_date: A datetime.

Returns

week number - The week number that contains the given date.

Examples

Input Output
week_of_year(datetime(2020-12-31)) 53
week_of_year(datetime(2020-06-15)) 25
week_of_year(datetime(1970-01-01)) 1
week_of_year(datetime(2000-01-01)) 52

Note

weekofyear() is an obsolete variant of this function. weekofyear() was not ISO 8601 compliant; the first week of a year was defined as the week with the year's first Wednesday in it. The current version of this function, week_of_year(), is ISO 8601 compliant; the first week of a year is defined as the week with the year's first Thursday in it.