// JavaScript to interpolate random images into a page.
    var ic = 4;                     // Number of alternative images
    var gpic = new Array(ic);          // Array to hold filenames
    gpic[0] = "ifrm/gpic0.html";
    gpic[1] = "ifrm/gpic1.html";
    gpic[2] = "ifrm/gpic2.html";
    gpic[3] = "ifrm/gpic3.html";
    
    function pickRandom(range) {
        if (Math.random)
            return Math.round(Math.random() * (range-1));
        else {
            var now = new Date();
            return (now.getTime() / 10) % range;
        }
    }

    // Picks an html page from above choices.
    var page = pickRandom(ic);