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;
   
   }

function isValidEmail(str) {
   return (str.indexOf(".") > 2) && (str.indexOf("@") > 0);
}

function popup(windowname)
{
	if(windowname == "writing")
	{
		 var mywindow = window.open ("writing_instrument.php", windowname,"location=1,status=1,scrollbars=1, width=712,height=618");
	  mywindow.focus();
	}else if(windowname == "rarity")
	{
		 var mywindow = window.open ("rarity_collection.php", windowname,"location=1,status=1,scrollbars=1, width=718,height=556");
	  mywindow.focus();
	}
}