function showCalculatorWindow() {
    var scX = Math.ceil((screen.width - 440)/2);
    var scY = Math.ceil((screen.height - 400)/2);
    var calcWindow = window.open('/calc/', '_calc','dependent=yes, width=400, height=360, innerHeight=360, innerWidth=400, location=no, menubar=no, resizable=no, scrollbars=no, titlebar=yes, toolbar=no, screenX='+scX+', screenY='+scY);
    calcWindow.focus();
    return false;
    
}