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student610
01-23-2004, 07:34 PM
Functions are a nightmare for me. I am trying to create a mortgage calculator. When I get this one done, I would like to use same format to create Present value and Future value calculators. Also, the onBlur"CheckInterest" function is not working either. Here's what I have:
<HTML>
<HEAD>
<TITLE>Mortgage Calculator</TITLE>
<STYLE>
BODY {color:white; background-color:blue}
</STYLE>
<SCRIPT TYPE="text/JavaScript">
<!---Hide from older browsers
function Monthly(I, N, S) {
// I = yearly interest rate;
// N = number of monthly payments;
// S = loan amount;
return(S*I/12*Math.pow(I/12+1,N))/(Math.pow(I/12+1,N)-1);
document.MORTGAGE.PAYMENT.value;
}
function ShowVal() {
var S=eval(document.MORTGAGE.LOAN.value);
var I=eval(document.MORTGAGE.INTEREST.value);
var N=eval(document.MORTGAGE.NUMBER.value);
var P=eval(document.MORTGAGE.PAYMENT.value);
document.MORTGAGE.TOTAL.value=P*N;
}
function CheckInterest() {
if(document.MORTGAGE.INTEREST <1) {
return value;
} else {
if(document.MORTGAGE.INTEREST >1) {
alert("Interest must be less than 1");
}
}
}
// Stop hiding--->
</SCRIPT>
</HEAD>
<BODY TEXT=WHITE; BGCOLOR="BLUE">
<P><H2>Mortgage Calculator</H2></P>
<FORM NAME=MORTGAGE>
<TABLE>
<TR>
<TD VALIGN=TOP ALIGN=RIGHT>Loan Amount:&nbsp<INPUT NAME=LOAN></TD>
</TR>
<TR>
<TD VALIGN=TOP ALIGN=RIGHT>Yearly Interest Rate:&nbsp<INPUT NAME=INTEREST onBlur="CheckInterest();"></TD>
</TR>
<TR>
<TD VALIGN=TOP ALIGN=RIGHT>Number of Payments:&nbsp<INPUT NAME=NUMBER></TD>
</TR>
<TR>
<TD VALIGN=TOP ALIGN=RIGHT>Monthly Payment Amount:&nbsp<INPUT NAME=PAYMENT onClick"Monthly()"></TD>
</TR>
<TD VALIGN=TOP ALIGN=RIGHT>Total Payments:&nbsp<INPUT NAME=TOTAL></TD>
</TR>
<TR>
<TD VALIGN=TOP ALIGN=CENTER><INPUT TYPE=BUTTON VALUE="Calculate" onClick="ShowVal(PAYMENT)">&nbsp;&nbsp;
<INPUT TYPE=BUTTON VALUE="Reload" onCLICK="location.reload();"></TD>
</TR>
</TABLE>
</FORM>
</BODY>
</HTML>
I would appreciate any feedback as I would like to use this on other web pages.
Thanks.