_IsEasterSunday()

[JohnOne]

You how you always need to check if its easter sunday on a certain date in a couple of years.

ConsoleWrite(_IsEasterSunday(31,3,2013) & @LF); d m yyyy

Func _IsEasterSunday($iday, $imonth, $iyear)

    If $iyear < 1 Or $iyear > 9999 Then
        Return False
        Exit
    EndIf

    $a = Mod($iyear, 19)
    $b = Mod($iyear, 4)
    $c = Mod($iyear, 7)
    $d = Mod(19 * $a + 24, 30)
    $e = Mod(2 * $b + 4 * $c + 6 * $d + 5, 7)
    $sunday = 22 + $d + $e
    $month = 3

    If $sunday > 31 Then
        $month = 4
        $sunday -= 31
    EndIf

    If $iday = $sunday And $imonth = $month Then
        Return True
    Else
        Return False
    EndIf

EndFunc

Sorry I couldnt find on on the forum.

[czardas]

Hehe, I had a go at this, but your version is much simpler. See EasterHodges There is also a link to the page where I got the algorithm. There are several different methods.

[JohnOne]

Dont know how I missed that, I probaby searched eastersunday

Someone sent the formula over a chat window, (riveting stuff it was)

Dosent mothers day (UK) change too? I wonder if theres a formula for that.

[czardas]

I find it quite annoying when all these dates keep changing. Didn't they try and change St. Patricks day a year ago. I suppose it's one of those social phenomenons. Still it would be useful to have a varied library of international public holiday dates. It would be pretty useful for international stuff.