Business::PT::NIF version 0.03 ============================== =head1 NAME Business::PT::NIF - Validate Portuguese NIF (Número Fiscal de Contribuinte) =head1 VERSION Version 0.01 =head1 SYNOPSIS use Business::PT::NIF; if ( valid_nif($nif) ) { # ... } =head1 FUNCTIONS =head2 valid_nif Validates Portuguese NIF's. Returns a true value if the validation succeeds, a false one otherwise. Currently, validation is done only by the control digit, as follows: 1) NIF is matched with /^\d{9}$/ (nine consecutive digits with nothing more) 2) Control digit (last one, the ninth) is removed and store 3) First digit is multiplied by 9, second by 8, third by 7, fourth by 6, fifth by 5, sixth by 4, seventh by 3, eight by 2 4) All the results of the multiplication are summed 5) Modulo of the sum by 11 is found 6) Complement of the sum by 11 is found 7) Control digit is compared to said complement Example for NIF 136695973 1) NIF is matched agains /^\d{9}$/, test passes 2) Control digit is 3 (last digit) 3) Multiplication: 1*9, 3*8, 6*7, 6*6, 9*5, 5*4, 9*3, 7*2 4) Sum of said products is 217 5) 217 % 11 = 8 6) 11 - 8 = 3 7) 3 == 3, test passes When the complement (the result of step 6) is greater than 9, the number is assumed to be 0. =head1 AUTHOR Jose Castro, C<< >> =head1 BUGS Please report any bugs or feature requests to C, or through the web interface at L. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes. =head1 SUPPORT You can find documentation for this module with the perldoc command. perldoc Business::PT::NIF You can also look for information at: =over 4 =item * AnnoCPAN: Annotated CPAN documentation L =item * CPAN Ratings L =item * RT: CPAN's request tracker L =item * Search CPAN L =back =head1 SEE ALSO http://chemeng.p.lodz.pl/zylla/ut/translation.html#PT =head1 ACKNOWLEDGEMENTS =head1 COPYRIGHT & LICENSE Copyright 2005 Jose Castro, all rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.