// JavaScript to interpolate random images into a page.
    var ic = 3;     // Number of alternative images
    var header = new Array(ic);  // Array to hold filenames
            
    header[0] = "images/headers/sig_header.gif";
    header[1] = "images/headers/green_R_header.gif";
    header[2] = "images/headers/green_rlogo_header.jpg"; 
    function pickRandom(range) {
       if (Math.random){
       		var temp =  Math.round(Math.random() * (range-1));
		while (temp==choice)
	            temp = Math.round(Math.random() * (range-1));
		return temp;
       }
       else {
	       var now = new Date();
	       return (now.getTime() / 1000) % range;
       }
   }
   var choice = pickRandom(ic);