Re: Calculating daylight savings time

It tells PHP which way to format various locale specific functions. (date stuff, money stuff, etc..) -Micah On Wednesday 20 August 2003 2:23 am, Lisi wrote: > I saw it, at first I didn't think it would work but it's great - just what > I need. I guess I was just surprised that there isn't an easier way to do > this in PHP by switching from the default. I also like to write my own code > rather than use someone else's, since it's the best way to learn, but in > this case it wasn't worth rewriting this function from scratch since it > does exactly what I need. > > I'm still confused though about setlocale - what does this do in plain > English? > > Thanks for the info, > > -Lisi > > At 10:05 AM 8/19/03 -0700, Micah Stevens wrote: > >Here's the example code I was talking about in the docs, you should really > >read the user submitted notes in the docs, they're very helpful, moreso > > than the docs from time to time. > > > >(this is not my code..) > > > >leafrink at hotmail dot com > > 28-Feb-2003 07:26 > > > > > > > >Wrote this function after a fair bit of searching on the subject. > >Don't know if it's the best way to do it, but it works. > > > >Its not that exact but it's pretty close. > > > >Hope it helps someone out there. > > > >/** > >* function for working out if it is daylight savings for a specific date. > >* must specify when daylight savings starts and ends in the format > >* "[1=First,2=Second,3=Third,4=Fourth,L=Last]:NameOfDay:Of The Month" > >* e.g. "L:Sun:3" = Last Sunday in March > >* some will not meet this criteria but most do. > >* > >* see - http://webexhibits.org/daylightsaving/g.html for > >daylight savings > >times around the world. > >* > >*/ > >function is_daylight_savings($gmtime,$DSTStart = '',$DSTEnd = ''){ > > //global $locale; > > //For Most Of Australia > > //DayLightSavings Starts Last sunday in October > > $DSTStart = "L:Sun:10";//$locale['DSTStart']; > > //DayLightSavings Ends Last Sunday in March > > $DSTEnd = "L:Sun:3";//$locale['DSTEnd']; > > > > $DSTStart = split(":",$DSTStart); > > $DSTEnd = split(":",$DSTEnd); > > > > $gmtMonth = date("n",$gmtime); > > // if not even in the Important changeover months. > > if ($gmtMonth < $DSTStart[2] && $gmtMonth > $DSTEnd[2]){ > > return false; > > } else if ($gmtMonth > $DSTStart[2] || $gmtMonth < $DSTEnd[2]) { > > return true; > > } else { > > //it is in the Start or End Month > > if ($gmtMonth == $DSTStart[2]){ > > $True = true; > > $week = $DSTStart[0]; > > $ImportantDay = $DSTStart[1]; > > } else {//it is in the End Month > > $True = false; > > $week = $DSTEnd[0]; > > $ImportantDay = $DSTEnd[1]; > > } > > //get the day of the month > > $gmtDay = date("j",$gmtime); > > //work out what week it starts/ends. > > if ($week == 'L'){ > > $week = 4; > > $ldom = 4;//last day of month factor > > } > > //if the week in which it starts/ends has not been reached > > if($gmtDay < ($week-1)*7){ > > return (!$True); > > } else { > > $gmtDate = getdate($gmtime); > > //go by a Day of the Week Basis > > for ($i=($week-1)*7;$i<(($week*7)+$ldom);$i++){ > > $checkDate = > > mktime(0,0,0,$gmtDate["mon"],$i,$gmtDate["year"]); > > //get the actual day it starts/ends > > if (date("D",$checkDate) == "Sun" && > > date("n",$checkDate) == > > $gmtMonth > >){ > > $day = date("j",$checkDate); > > } > > } > > if ($gmtDay < $day) {//if it has not reached the day > > return (!$True); > > } else { > > return $True; > > } > > } > > } > >} > > > >//Testing > >if(is_daylight_savings(strtotime("26-Oct-2003"))){ > > echo "is DAYLIGHT SAVINGS"; > >}else { > > echo "is NOT DAYLIGHT SAVINGS"; > >} > > > >On Tuesday 19 August 2003 2:37 am, Lisi wrote: > > > What I need to do is figure this out for more than one location at a > > > time. I am displaying Sabbath times for several different cities around > > > the world at once (New York, London, Paris, Jerusalem, Sydney) - i.e. a > > > certain amount of time before sunset, different for each city and each > > > city is in a different dst zone. > > > > > > Can I do something using setlocale, to change timezones to the city I > > > need, and then use date(I)? Or does date(I) always work only for the > > > US? And what exactly does setlocale change? I couldn't figure out from > > > the notes on php.net. > > > > > > Thanks for your help, > > > > > > -Lisi > > > > > > At 12:06 AM 8/17/03 -0700, Micah Stevens wrote: > > > >As an afterthought, the docs are inspecific on who's daylight savings > > > >schedule > > > >that the function returns. There's another user submitted function in > > > > the comments list that takes into account a specific schedule. > > > > > > > >-Micah > > > > > > > >On Sunday 17 August 2003 12:43 am, Lisi wrote: > > > > > I have sunset times stored in a database and the a PHP page that > > > > > performs a number of calculations on the retrieved time. One of the > > > > > things I need to figure out is whether or not to add an hour for > > > > > Daylight Savings Time. Since there is more than once location, and > > > > > each one begins and ends DST at a different time, I need to figure > > > > > this out based on location. My question is, how do I figure out > > > > > whether it's the "first sunday in April" yet or not? I know > > > > > it has > > > > > to do with the date() function somehow, I'm just not sure how to > > > > > use it properly in this case - any suggestions? > > > > > > > > > > Thanks, > > > > > > > > > > -Lisi > > > >-- > >PHP Database Mailing List (http://www.php.net/) > >To unsubscribe, visit: http://www.php.net/unsub.php