Algorithm-Verhoeff version 0.1 ============================== DESCRIPTION This module implements Verhoeff's check digit algorithm. It provides a method to generate check digits from numbers, and a method to verify if an existing number passes the check. Using numbers that pass the verhoeff check is useful for things like product codes. This is because such numbers almost never pass the verhoeff check if they as mis-typed. This includes common typos such as ommitted or repeated digits, transposed digits and so on. Since it only adds a single digit onto what might already be a longish number, it's a good algorithm for use where humans need to enter or read the numbers. To generate such a number, pick a starting number, call verhoeff_check() to get a check digit, and then APPEND that digit to the end of the original number. The new number will how pass the verhoeff_check(). INSTALLATION To install this module type the following: perl Makefile.PL make make test make install DEPENDENCIES None, although using this with integers > 32bit will require the bignum module. COPYRIGHT AND LICENCE Copyright (C) 2004 by Jon Peterson This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself, either Perl version 5.8.4 or, at your option, any later version of Perl 5 you may have available.