What am I doing wrong? thanks





<SCRIPT LANGUAGE="JavaScript">
<!--
function checkForZero(field) {
if (field.value == 0 || field.value.length == 0) {
alert ("This field can't be 0!");
field.focus(); }
else
calculatePayment(field.form);
}

function cmdCalc_Click(form) {
if (form.price.value == 0 || form.price.value.length == 0) {
alert ("The Price field can't be 0!");
form.price.focus(); }
else if (form.ir.value == 0 || form.ir.value.length == 0) {
alert ("The Interest Rate field can't be 0!");
form.ir.focus(); }
else if (form.term.value == 0 || form.term.value.length == 0) {
alert ("The Term field can't be 0!");
form.term.focus(); }
else
calculatePayment(form);
}

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;
}
//-->
</SCRIPT>