function open_window(url) {
	mywin = window.open(url,"isswin",'toolbar=0,location=0,directories=0,status=0,menubar=0,scrollbars=0,resizable=0,width=190,height=280');
}

function ValidateInput(checkVal){
        len = checkVal.length;
        for (i = 0; i<len; i++) {
        if (!((checkVal.substring(i, i+1)=="0") ||
                (checkVal.substring(i,i+1)=="1") ||
                (checkVal.substring(i,i+1)=="2") ||
                (checkVal.substring(i,i+1)=="3") ||
                (checkVal.substring(i,i+1)=="4") ||
                (checkVal.substring(i,i+1)=="5") ||
                (checkVal.substring(i,i+1)=="6") ||
                (checkVal.substring(i,i+1)=="7") ||
                (checkVal.substring(i,i+1)=="8") ||
                (checkVal.substring(i,i+1)=="9"))) {
                	errorMsg = "You have entered an invalid number. Please enter a new amount and try again.";
                	return true;
                }
        }
        if (!((checkVal >= 0) & (checkVal < 300))) {
                errorMsg = "Numbers way out of range";
                return true;
        } else {
        return false;
        }
}

function isGreater(a,b) {
	if (Math.abs(a) < Math.abs(b)) return -1;
	else
	if (Math.abs(b) == Math.abs(a)) return 0;
	return 1;
}


function doISSStuff(form)  {

	var badnum = 0;
	var iss = 0;
	var issA = 0;
	var issB = 0;
	var issC = 0;

	ais = new Array(6);
	sortais = new Array(6);
	ais[0] = document.isscalc.head.value;
	ais[1] = document.isscalc.face.value;
	ais[2] = document.isscalc.ches.value;
	ais[3] = document.isscalc.abdo.value;
	ais[4] = document.isscalc.limb.value;
	ais[5] = document.isscalc.skin.value;

	for (j=0; j<6; j++) {
	    if (ValidateInput(ais[j])) {
		    window.alert(errorMsg);
			badnum = -1;
	    }
		if ((ais[j]<0) || (ais[j]>6)) {
			alert('AIS out of range (0 - 6)');
			badnum = -1;
		}
	}

	aissort = ais.sort(isGreater);

	issA = aissort[3]*aissort[3];
	issB = aissort[4]*aissort[4];
	issC = aissort[5]*aissort[5];

	if (badnum == 0) {
		if (issC == 36)
			iss = 75;
		else
			iss = issA + issB + issC;
	}
	else
		iss = 0;

    document.isscalc.issscore.value = iss;
}