var numPics = 5;

function setHeader () {
	var num = Math.floor(Math.random() * numPics) + 1;
	document.write('<img src="/wgs/images/collage' + num.toString() + '.jpg" alt="" />');
	return true;
}

// alternating colored rows
//
// remember to define a default color on the table rows via CSS
// for users with javascript turned off
//
// function sets className of even- and odd-numbered rows in a table
//
//    usage: body onload="altrows('<classname>');"
//    CSS definition: 
//       table.<classname> tr.odd {
//             background-color: <odd row color>;
//       }
//       table.<classname> tr.even {
//             background-color: <even row color>;
//       }
//
// mw combined script from an alternating rows script by id by rjw, and 
// one by w0lverine on forums.devarticles.com - 
// http://forums.devarticles.com/t714/s.html

function getElementsByClassName(ClassName,tagName,parentElement){
	var elements=new Array();
	var d=parentElement ? parentElement : document;
	var allElements;

	if(tagName)
	  allElements=d.all && d.all.tags(tagName)
	   || d.getElementsByTagName && d.getElementsByTagName(tagName);
	else allElements=d.all || d.getElementsByTagName("*");
	
	for(var i=0,len=allElements.length; i<len; i++)
	 if(allElements[i].className==ClassName)
	  elements[elements.length]=allElements[i];

	return elements;
}

function altrows(classname) {
var tableElements = getElementsByClassName(classname) ;
var table = tableElements[tableElements.length - 1] ;

var i, rows = table.getElementsByTagName("tr");
	     for (i = 0; i < rows.length; i++) {
	       if (i % 2 == 0) {
	         rows[i].className = "odd";
	       }
	       else {
	         rows[i].className = "even";
	       }
	  }
}