Month since a special date (in decimal)

Question

I would like to have a function that could display how many months it's been since a special date – with decimals if possible.
Anyone have an idea on how to make it? (In PHP)

I ended up doing the following:
$var = ((mktime(0,0,0,8,3,2009) - mktime(0,0,0,9,3,2009))/86400/30.4368499);
Your answers were helpful. James Goodwins was the one leading me to this so he get the "answer solved" mark.

Answer 1

function dateDiff($dformat, $endDate, $beginDate)
{
$date_parts1=explode($dformat, $beginDate);
$date_parts2=explode($dformat, $endDate);
$start_date=gregoriantojd($date_parts1[0], $date_parts1[1], $date_parts1[2]);
$end_date=gregoriantojd($date_parts2[0], $date_parts2[1], $date_parts2[2]);
return $end_date - $start_date;
}

Answer 2

Try this:

echo NumberOfMonths(strtotime('2009-10-02'),strtotime('2008-12-02'));

function NumberOfMonths($date1, $date2) {
 $dates = array(explode(' ',date('Y n',$date1)),explode(' ',date('Y n',$date2)));
 return ($dates[0][0]-$dates[1][0])*12+($dates[0][1]-$dates[1][1]);
}

Although there's no validation on it of course.