note 101170 added to function.date-sunrise

Care should be taken to ensure that time zones and daylight saving are handled correctly when using these functions. <? $date = new DateTime('2010-12-21'); // Midwinter $tz = new DateTimeZone("Europe/London"); $date->setTimezone($tz); $date->setTime(12,0,0); $t = $date->getTimestamp(); $respr = date_sunrise($t,SUNFUNCS_RET_STRING,52.58,-2.133); $resps = date_sunset($t,SUNFUNCS_RET_STRING,52.58,-2.133); echo date("c",$t) . "\n"; echo "Rise = " . $respr . " Set = " . $resps . "\n"; $date->setDate(2010,6,24); // Midsummer $date->setTime(12,0,0); $t = $date->getTimestamp(); $respr = date_sunrise($t,SUNFUNCS_RET_STRING,52.58,2.133); $resps = date_sunset($t,SUNFUNCS_RET_STRING,52.58,2.133); echo date("c",$t) . "\n"; echo "Rise = " . $respr . " Set = " . $resps . "\n"; ?> which produces the output below (lat/long are for Wolverhampton, England) 2010-12-21T12:00:00+00:00 Rise = 09:17 Set = 16:56 2010-06-24T12:00:00+01:00 Rise = 04:28 Set = 21:19 The figures for June are correct using daylight saving time, the figures for December are 1 hour late, as if daylight saving time adjustment was still being applied. The two values of $t differ by 180 days and 1 hour as they should. Sunrise and sunset times checked using http://sunrise-sunset.dusk-dawn.com ---- Server IP: 87.124.126.138 Probable Submitter: 82.37.6.187 (proxied: 82.37.6.187) ---- Manual Page -- http://www.php.net/manual/en/function.date-sunrise.php Edit -- https://master.php.net/note/edit/101170 Del: integrated -- https://master.php.net/note/delete/101170/integrated Del: useless -- https://master.php.net/note/delete/101170/useless Del: bad code -- https://master.php.net/note/delete/101170/bad+code Del: spam -- https://master.php.net/note/delete/101170/spam Del: non-english -- https://master.php.net/note/delete/101170/non-english Del: in docs -- https://master.php.net/note/delete/101170/in+docs Del: other reasons-- https://master.php.net/note/delete/101170 Reject -- https://master.php.net/note/reject/101170 Search -- https://master.php.net/manage/user-notes.php