// helper method to get the value from a url-querystring variable
function getQueryVariable(variable) {
	var query = window.location.search.substring(1);
	var vars = query.split("&");
	for (var i=0;i<vars.length;i++) {
		var pair = vars[i].split("=");
		if (pair[0] == variable) {
			return pair[1];
		}
	}
	//alert('Query Variable ' + variable + ' not found');
	return "";
}

// simple test if a textstring is numeric or not
function isNumeric(sText)
{
   var ValidChars = "0123456789";
   var IsNumber=true;
   var Char;
   for (i = 0; i < sText.length && IsNumber == true; i++) { 
      Char = sText.charAt(i); 
      if (ValidChars.indexOf(Char) == -1){
         IsNumber = false;
      }
   }
   return IsNumber;
}

// http://www.dustindiaz.com/top-ten-javascript/
function $() {
	var elements = new Array();
	for (var i = 0; i < arguments.length; i++) {
		var element = arguments[i];
		if (typeof element == 'string')
			element = document.getElementById(element);
		if (arguments.length == 1)
			return element;
		elements.push(element);
	}
	return elements;
}