[Resolved] Monday of the first week of the year?

[kemu_]

How could i get what is the date of the first monday of the year ?? Depending of the year it usually is last days on December of the year before or 1.1.xxxx....

Suggestions?

[drawmack]

<?php
//days of the week, position used later
//you'll want to test and make sure I used the correct
//abbreviations because I don't feel like it.
$days = array('mon','sun','sat','fri','thu','wed','tue');

//generate a unix timestamp of the date we want
$when = strtotime('01-01-2003');

//get the day of the week
$dow = date('D',$when);

//the position of this day in our array
$i = 0;
while($dow != $days[$i]) {$i++;}

//and the first monday of the year is
$first_monday = $i + 1;
?>

http://www.php.net/strtotime
http://www.php.net/date

[kemu_]

well, that didnt quite work, but i figured how to get it working... thx 🙂

[drawmack]

mind posting the implementation you used?

[kemu_]

//Get the date of the first day of the year
$firstmonday =mktime(0,0,0,1,1,$year);

if(date("w",$firstmonday)==1){ // if the day of the week is monday, first monday of the year is 1.1
	$firstmonday=date("D j M Y",$firstmonday);
}else{ // otherwise we check the weekday of the first day, and substract its value from the last day of previous year....voilâ
	$day = date("w",$firstmonday);
	if($day==0) $day=7;
	$firstmonday=date("D j M Y",mktime(0,0,0, 12,31 - $day + 2, $year - 1));
}

[Weedpacket]

Strictly speaking though, that will sometimes give you the Monday of the last week of the previous year: by current standards If January 1 is a Friday, Saturday, or Sunday then the first Monday of the year is January 4, 3 or 2 (the week number returned by date('W') reflects this.)

So with that in mind I came up with a little bit of an algorithm I described here