function calculatePolar(){
    var x = $F('x');
    var y = $F('y');
    var r = Math.pow((Math.pow(x,2) + Math.pow(y,2)),0.5);
    var theta = Math.atan(y/x)*360/2/Math.PI;
    if (x >= 0 && y >= 0) {
        theta = theta;
    } else if (x < 0 && y >= 0) {
        theta = 180 + theta;
    } else if (x < 0 && y < 0) {
        theta = 180 + theta;
    } else if (x > 0 && y < 0) {
        theta = 360 + theta;
    }

    //Box.ajaxReq('/docs/scripts/conv.js',false);
    var msg = ""
        + "Polar Coordinates (" + Conv.rounding(r) + ", " + Conv.rounding(theta) + ")\n"
        + "";
    alert(msg);
}

function calculateCartesian(){
    var r = $F('r');
    var theta = $F('theta');
    var x = r * Math.cos(theta * 2 * Math.PI / 360);
    var y = r * Math.sin(theta * 2 * Math.PI / 360);
    //Box.ajaxReq('/docs/scripts/conv.js',false);
    var msg = ""
        + "Cartesian Coordinates (" + Conv.rounding(x) + ", " + Conv.rounding(y) + ")\n"
        + "";
    alert(msg);
}