<!--

function checkForm(form)
{
    if (form.price.value == 0 || form.price.value.length == 0) {
        alert ("The Price field can't be 0!");
        form.price.focus(); 
		return false;
	}
	else if (form.price.value.indexOf(",") != -1) {
		alert("Price field should not contain commas for computing");
		form.price.focus(); 
		return false;
	}
	else if (form.dp.value.indexOf(",") != -1) {
		alert("Down Payment field should not contain commas for computing");
		form.dp.focus(); 
		return false;
	}

    else if (form.ir.value == 0 || form.ir.value.length == 0) {
        alert ("The Interest Rate field can't be 0!");
        form.ir.focus(); 
		return false;
	}
    else if (form.term.value == 0 || form.term.value.length == 0) {
        alert ("The Term field can't be 0!");
        form.term.focus(); 
		return false;
	}
    else {
        calculatePayment(form);
		return true;
	}
}

function calculatePayment(form)
{
	princ = form.price.value - form.dp.value;
    intRate = (form.ir.value/100) / 12;
    months = form.term.value * 12;
    form.pmt.value = Math.floor((princ*intRate)/(1-Math.pow(1+intRate,(-1*months)))*100)/100;
    form.principle.value = princ;
    form.payments.value = months;
}
//-->