<!--
function checkNumber(input, min, max, msg)
{
	msg = msg + " field has invalid data: " + input.value;
	var str = input.value;
	for (var i = 0; i < str.length; i++) {
		var ch = str.substring(i, i + 1)
		if ((ch < "0" || "9" < ch) && ch != '.') {
			alert(msg);
			return false;
		}
	}
	var num = parseFloat(str)
	if (num < min || max < num) {
		alert(msg + " not in range [" + min + ".." + max + "]");
		return false;
	}
	input.value = str;
	return true;
}
function computeField(input)
{
	if ((input.value != null) && (input.value.length != 0) && !isNaN(parseFloat(input.value)))
	{
		input.value = parseFloat(input.value);
	}
	computeForm(input.form);
}

function commaSplit(srcNumber) {
	var txtNumber = '' + srcNumber;
	if (isNaN(txtNumber) || txtNumber == "") {
		alert("Invalid number.	Please try again.");
		fieldName.select();
		fieldName.focus();
	} else {
		var rxSplit = new RegExp('([0-9])([0-9][0-9][0-9][,.])');
		var arrNumber = txtNumber.split('.');
		arrNumber[0] += '.';
		do {
		arrNumber[0] = arrNumber[0].replace(rxSplit, '$1,$2');
		} while (rxSplit.test(arrNumber[0]));
		if (arrNumber.length > 1) {
			return arrNumber.join('');
		} else {
			return arrNumber[0].split('.')[0];
		}
	}
}

function computeForm(form)
{
	if ((form.employees.value == null || form.employees.value.length == 0) ||
		(form.wasted.value == null || form.wasted.value.length == 0) ||
		(form.costing.value == null || form.costing.value.length == 0))
	{
		return;
	}
	if (!checkNumber(form.employees, 1, 9999999, "Number of Employees") ||
		!checkNumber(form.wasted, 0.1, 9999999, "Wasted Time") ||
		!checkNumber(form.costing, 1, 9999999, "Costing Me"))
	{
		form.saveperday.value = "Invalid Data";
		form.saveperweek.value = "Invalid Data";
		form.saveinyear.value = "Invalid Data";
		return;
	}
	
	var dayNum = Digits(((form.costing.value * form.employees.value) * form.wasted.value / 9),2)
	var weekNum = Digits(((form.costing.value * form.employees.value) * form.wasted.value),2)
	var yearNum = Digits(((form.costing.value * form.employees.value) * form.wasted.value * 47),2)
	var returnNum = Digits(parseFloat(form.buyingprice.value / weekNum)+1,0)
	returnNum = parseFloat(returnNum)
	if (form.buyingprice.value == "")
	{
		returnNum = ""
	}
	
	form.saveperday.value =	commaSplit (dayNum)
	form.saveperweek.value = commaSplit (weekNum)
	form.saveinyear.value = commaSplit (yearNum)
	form.returnweeks.value = returnNum
	
	if (returnNum != "")
	{
		alert ("Weeks to cover the cost of PureSight: " + returnNum)
	}
	
	
}
function clearForm(form)
{
	form.employees.value = "";
	form.wasted.value = "1.0";
	form.costing.value = "40000"
	form.saveperday.value = "";
	form.saveperweek.value = "";
	form.saveinyear.value = "";

}
function Digits(aNumber, digits)
{
	var str = "" + aNumber
	var b = str.lastIndexOf(".")
	if (b < 0) str += "."
	for (var i = 0; i < digits; i++) str += "0"
	if (b >= 0) return(str).substring(0,b+1+digits)
	return str
}


// -->