Hi all, Just a quick note to see if anyone has already written a function to calculate a 'standard deviation' or a 'weighted mean' function? I have created these functions as I could not find any references so if anybody wants/needs a copy simply say. Kind Regards Rob -- PHP Development Mailing List <http://www.php.net/> To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] To contact the list administrators, e-mail: [EMAIL PROTECTED]