function changehighlight(imgid,imgsrc,imgalt)
{
document.getElementById(imgid).src=imgsrc;
document.getElementById(imgid).alt=imgalt;
}
function changedark(imgid,imgsrc,imgalt)
{
document.getElementById(imgid).src=imgsrc;
document.getElementById(imgid).alt=imgalt;
}
function changebgcolor(element, color)
{
	document.getElementById(element).style.backgroundColor = color;
}
function showitem(itemid)
{
	if(document.getElementById(itemid).style.display == "none")
		document.getElementById(itemid).style.display = "block";
	else
		document.getElementById(itemid).style.display = "none";
}

//display chart
var img;
var display_height;
var display_width;
var ratio;
var step = 40;
var speed = 8;
var sh;
function chart_display(cover_div, img_src, display_width, display_height){
	var cover = document.getElementById(cover_div);
	cover.style.top = "0px";
	cover.style.display = "block";
	cover.innerHTML = "<img id='js_display_chart' src='" + img_src + "'   height=1  width=1 > ";
	this.img = document.getElementById("js_display_chart");
	this.display_height = display_height;
	this.display_width = display_width;
	this.ratio = display_width/display_height;
	sh=setInterval("chart_display_scoll()", speed);
}
function chart_display_scoll(){
	img.width = img.width+ratio*speed ;
  	img.height = img.height+speed;
  	if (img.height >= display_height || img.width >= display_width){
		clearInterval(sh)
	}
}