perlfaq4: How do I find the week-of-the-year/day-of-the-year?
[email protected] (_brian_d_foy)
| Newsgroups | perl.perlfaq.workers,perl.documentation |
|---|---|
| Message-ID | <260120031221345894%[email protected]> |
* re-jiggered the question to get rid of the hyphens * expanded the answer using POSIX, Time::Local, and Date::Calc Index: perlfaq.pod =================================================================== RCS file: /cvs/public/perlfaq/perlfaq.pod,v retrieving revision 1.17 diff -u -d -r1.17 perlfaq.pod --- perlfaq.pod 26 Jan 2003 17:45:46 -0000 1.17 +++ perlfaq.pod 26 Jan 2003 18:19:54 -0000 @@ -412,7 +412,7 @@ =item * -How do I find the week-of-the-year/day-of-the-year? +How do I find the day or week of the year? =item * Index: perlfaq4.pod =================================================================== RCS file: /cvs/public/perlfaq/perlfaq4.pod,v retrieving revision 1.40 diff -u -d -r1.40 perlfaq4.pod --- perlfaq4.pod 26 Jan 2003 17:43:21 -0000 1.40 +++ perlfaq4.pod 26 Jan 2003 18:19:56 -0000 @@ -353,13 +353,34 @@ =head1 Data: Dates -=head2 How do I find the week-of-the-year/day-of-the-year? +=head2 How do I find the day or week of the year? -The day of the year is in the array returned by localtime() (see -L<perlfunc/"localtime">): +The localtime function returns the day of the week. Without an +argument localtime returns the current seconds since the epoch. - $day_of_year = (localtime(time()))[7]; + $day_of_year = (localtime)[7]; + +The POSIX module can also format a date as the day of the year or +week of the year. + + use POSIX qw/strftime/; + my $day_of_year = strftime "%j", localtime; + my $week_of_year = strftime "%W", localtime; +To get the day of year for any date, use the Time::Local module to get +a time in epoch seconds for the argument to localtime. + + use POSIX qw/strftime/; + use Time::Local; + my $week_of_year = strftime "%W", + localtime( timelocal( 0, 0, 0, 18, 11, 1987 ) ); + +The Date::Calc module provides two functions for to calculate these. + + use Date::Calc; + my $day_of_year = Day_of_Year( 1987, 12, 18 ); + my $week_of_year = Week_of_Year( 1987, 12, 18 ); + =head2 How do I find the current century or millennium? Use the following simple functions: -- brian d foy, [email protected]