// for enlarging article images in a new window
function imageWindow(ajax_dir, id, num) 
{
		imgWindow = window.open(ajax_dir + '/image_popup.php?image=' + id + '&image_id=' + num ,'popupWindow','toolbar=no,location=no,directories=no,status=no,menubar=no,scrollbars=no,resizable=yes,copyhistory=no,width=700,height=650,screenX=150,screenY=150,top=150,left=150')
		imgWindow.focus();
}  






// toggles between select all/deselect all on checkboxes
//
// check_all - whether to check all or de-check all
// form - form element that checkbox array belongs to
// checkbox_arr_name - name of checkbox array
function toggleCheck(check_all, form, checkbox_arr_name)
{                            
    var arr = form.elements[checkbox_arr_name];  

     for(i = 0; i < arr.length; i++) {
         arr[i].checked = check_all;
     } 
}



  

// check if at least one checkbox is checked in a checkbox array
// form - form element that checkbox array belongs to
// box_arr_name - name of checkbox/radio array
function at_least_one_checked(form, box_arr_name)
{
  var arr = form.elements[box_arr_name]; 
  
   for(var i = 0; i < arr.length; i++) {
        if(arr[i].checked) return true;
   } 
   return false;

}
  
 
// for disabling a group of checkboxes, except the one with value, non
function setNone(form, box_arr_name, non)
{
   var arr = form.elements[box_arr_name];

    
   if((arr[arr.length-1].checked == true) && 
	   (arr[arr.length-1].value == non))
   {		   
	  for(var i = 0; i < arr.length-1; i++)
	  {
		  arr[i].checked = false;
      }
   }
	 
}