// <![CDATA[

function do_loan_calc() {

	var principal_amount 		= $F("principal_amount");
	principal_amount 			= principal_amount.replace(/,/g,'');
	principal_amount			= Math.abs(principal_amount);

	var down_payment_percent 	= $F("down_payment_percent");
	down_payment_percent 		= down_payment_percent.replace(/,/g,'');
	down_payment_percent 		= Math.abs(down_payment_percent);

	var interest_rate 			= $F("interest_rate");
	interest_rate 				= Math.abs(interest_rate);

	var term_length_years 		= $F("term_length_years");
	term_length_years 			= Math.abs(term_length_years);
		
	var down_payment_amount 	= (principal_amount * down_payment_percent) / 100;
	//alert("down_payment_amount=["+down_payment_amount+"]");

	// The actual finance amount is the item amount less any down payments. 
	principal_amount			= principal_amount - down_payment_amount;
	
	var has_errors = false;
	if (principal_amount < 1)
	{
		$('principal_amount_err').innerHTML 	= "Please provide a loan amount.";
		has_errors = true;
	}
	else
		$('principal_amount_err').innerHTML 	= "";

	//$('down_payment_percent_err').innerHTML 		= down_payment_amount;

	if (interest_rate < 1)
	{
		$('interest_rate_err').innerHTML 		= "Please provide a correct Interest rate.";
		has_errors = true;
	}
	else
		$('interest_rate_err').innerHTML 		= "";

	if (term_length_years < 1)
	{
		$('term_length_years_err').innerHTML 	= "Please provide a term length.";
		has_errors = true;
	}
	else
		$('term_length_years_err').innerHTML 	= "";

	if (has_errors == true)
		return false;
	
	
	var month_interest 		= interest_rate/(12*100);    // Monthly interest in decimal form 
	var term_length_months 	= term_length_years * 12;    // Number of months 
	
	var n_term_length_months = term_length_months * -1;
	var calc1 = 1 - (Math.pow((month_interest + 1), n_term_length_months )); 
	//alert("calc1=["+calc1+"]");

	var monthly_payment_amount = principal_amount * (month_interest / calc1);
	monthly_payment_amount = monthly_payment_amount * 100;
	monthly_payment_amount = Math.round(monthly_payment_amount);
	monthly_payment_amount = monthly_payment_amount / 100;
	var ele_monthly_payment_amount = $('monthly_payment_amount');
	ele_monthly_payment_amount.value = monthly_payment_amount;

	return false;
}

function noNumbers(e)
{
	return true;

	var keynum
	var keychar
	var numcheck

	if(window.event) // IE
	{
		keynum = e.keyCode
	}
	else if(e.which) // Netscape/Firefox/Opera
	{
		keynum = e.which
	}
	keychar = String.fromCharCode(keynum)
	alert("keynum=["+keynum+"] keychar=["+keychar+"]");
	if ((keychar == '.') || (keynum == '9') ||(keynum == '63234') ||(keynum == '62345'))
	{
		return true;
	}
	if (keynum > 47 && keynum < 58)
	{
		return true;
	}	
	return false;
}
// ]]>