Fehler in "date.au3" - v3.3.8.1

; #FUNCTION# ====================================================================================================================
; Author ........: Tuape
; Modified.......: JdeB: modified to UDF standards & Doc., Change calculation logic.
; ===============================================================================================================================
Func _WeekNumberISO($iYear = @YEAR, $iMonth = @MON, $iDay = @MDAY)
	; Check for erroneous input in $Day, $Month & $Year
	If $iDay > 31 Or $iDay < 1 Then
		Return SetError(1, 0, -1)
	ElseIf Not __DateIsMonth($iMonth) Then
		Return SetError(2, 0, -1)
	ElseIf $iYear < 1 Or $iYear > 2999 Then
		Return SetError(3, 0, -1)
	EndIf


	Local $iDow = _DateToDayOfWeekISO($iYear, $iMonth, $iDay) - 1;
	Local $iDow0101 = _DateToDayOfWeekISO($iYear, 1, 1) - 1;


	If ($iMonth = 1 And 3 < $iDow0101 And $iDow0101 < 7 - ($iDay - 1)) Then
		;days before week 1 of the current year have the same week number as
		;the last day of the last week of the previous year
		$iDow = $iDow0101 - 1;
		$iDow0101 = _DateToDayOfWeekISO($iYear - 1, 1, 1) - 1;
		$iMonth = 12
		$iDay = 31
		$iYear = $iYear - 1
	ElseIf ($iMonth = 12 And 30 - ($iDay - 1) < _DateToDayOfWeekISO($iYear + 1, 1, 1) - 1 And _DateToDayOfWeekISO($iYear + 1, 1, 1) - 1 < 4) Then
		; days after the last week of the current year have the same week number as
		; the first day of the next year, (i.e. 1)
		Return 1;
	EndIf


	Return Int((_DateToDayOfWeekISO($iYear, 1, 1) - 1 < 4) + 4 * ($iMonth - 1) + (2 * ($iMonth - 1) + ($iDay - 1) + $iDow0101 - $iDow + 6) * 36 / 256)
EndFunc   ;==>_WeekNumberISO