function calcpayment()
{
	var bad = 0; 
	var mpayment = 0; 
	var tpayment = 0; 
	var spayment = 0; 
	var i = 0; 
	var robot = "a";
	var builder = ""; 
	var stringer = "a";
	
	
	stringer =  document.getElementById("loanCalc_amount").value;
	
	for (i = 0; i < stringer.length; i++)
	{
		robot = stringer.substring(i, i+1);
		if (robot != "," && robot != "$") 
		{
			builder = builder + robot; 
		}
	}
	
	amount = parseInt(builder, 10);
	months = parseInt(document.getElementById("months").options[document.getElementById("months").options.selectedIndex].value,10);
	interest = parseInt(document.getElementById("interest").options[document.getElementById("interest").options.selectedIndex].value,10)/1200;
	
	if (isNaN(amount))
	{
		bad = 1;
		amount = 0;
		document.getElementById("loanCalc_amount").value = "*REQUIRED"
	}
	else if (amount <= 0 || isNaN(amount))
	{
		bad = 1;
		amount = 0;
		document.getElementById("loanCalc_amount").value = "*REQUIRED"
	}
	else if(months <= 0 || isNaN(months))
	{
		alert("Must enter a term length.");
		bad = 1;
	}
	else if(interest <= 0 || isNaN(interest))
	{
		alert("Please select an interest rate.");
		bad = 1;
	}
	
	if (bad == 0)
	{
		mpayment = (interest * (Math.pow((1 + interest),months))) / ((Math.pow((1 + interest),months)) - 1) * amount;
		mpayment = parseInt (mpayment*100,10) / 100;
		document.getElementById("payment").innerHTML = "$" + formatCommas(mpayment.toFixed(2));
	
		
	
		interest = (parseInt(document.getElementById("interest").options[document.getElementById("interest").options.selectedIndex].value,10)+2)/1200;
		tpayment = (interest * (Math.pow((1 + interest),months))) / ((Math.pow((1 + interest),months)) - 1) * amount;
		tpayment = parseInt (tpayment*100,10) / 100;
		//document.calc.theirpayment.value=tpayment;
		spayment = (tpayment - mpayment) * months;
		spayment = parseInt (spayment*100,10) / 100;
		//document.calc.yousave.value=spayment;
	}
}

function formatCommas(intStr)
{
	var re = /(-?\d+)(\d{3})/;
	while (re.test(intStr))
	{
		intStr = intStr.replace(re, "$1,$2");
	}
	
	return(intStr);
}