JavaScript n00b in dire need of help

[FlightofIcarus]

Hey guys

so I'm taking an online JavaScript class at school, but unfortunately, I don't find our textbook very useful, and have been struggling with a lot of stuff in there, largely due to the fact that much guesswork is expected at the end of the chapters on the assignments (Course Technology's )New Perspectives on JavaScript. I don't find guessing to be a very effective learning method, so without further ado, here's the situation.

The assignment involves basic concepts around using arrays, and the for and while loops. We were supposed to create a database of contact information by inserting an external .js file, and using the arrays from that. Most of this is complete, but I'm stuck trying to figure out how to do the last part here, which is to try and return a numeric value in a side table from a for loop..

Here is the function part of it in question...

_______________________________
<title>The Lighthouse</title>
<link href="lhouse.css" rel="stylesheet" type="text/css" />
<script src = "list.js" type = "text/javascript"></script>
<script type = "text/javascript">

function amountTotal() {

var total = 0;

for(var i=0; i<amount.length;i++);

{

total = amount[i];

}

return total;

}
</script>
</head>
________________________________________

And here is the table in which the value is supposed to be written.
________________________________________

<div id="totals">
<script type = "text/javascript">

document.write ("<table border='1' rules = 'rows' cellspacing='0'>");

document.write ("<tr>");

document.write ("<th id='sumTitle' colspan='2'>");

document.write ("Summary");

document.write ("</th>");

document.write ("</tr>");

document.write ("<tr>");

document.write ("<th>Contributors</th>");

document.write ("<td>"+contributions+"</td>");

document.write ("</tr>");

document.write ("<tr>");

document.write ("<th>Amount</th>");

document.write ("<td>"+total+"</td>");

document.write ("</tr>");

document.write ("</table>");

</script>

</div>

</body>
</html>
_________________________________

If it helps, I get an error message in the file saying that "total" and "contributions" is not defined.

(This is the only text in the file concerning my problem, so I didn't bother posting the whole thing)

Help?

[criterion9]

From what you posted all I can tell you is that those two variables are not being defined.

[FlightofIcarus]

Yeah, unfortunately, the book isn't very clear on what to do :/ There's a step listed about declaring the total variable, but that's about all they're willing to tell you.

[criterion9]

Is that all the code you have?

[iokosan]

erm... what's inside list.js? amount array should be defined there...

[Mayday]

As you find your textbook to be vague in explanations, you may want to suppliment your book/class teachings with an online tutorial or two.

Such as:
http://www.w3schools.com/js/default.asp
http://www.tizag.com/javascriptT/index.php
http://www.htmlgoodies.com/primers/jsp/

Even if you don't want to go through whole tutorials, you may at least find explanations of a particular aspect to be helpful.