NAME

CheckDigits::M11_016 - compute check digits vor VAT Registration Number (PL)

SYNOPSIS

  use Algorithm::CheckDigits;
  $nip = CheckDigits('nip');
  if ($nip->is_valid('8567346215')) {
        # do something
  }
  $cn = $nip->complete('856734621');
  # $cn = '8567346215'
  $cd = $nip->checkdigit('856734621');
  # $cd = '5'
  $bn = $nip->basenumber('8567346215');
  # $bn = '856734621';

DESCRIPTION

ALGORITHM

1.: Beginning left every digit is weighted with 6, 5, 7, 2, 3, 4, 5, 6, 7
2.: The weighted digits are added.
3.: The sum from step 2 is taken modulo 11.
4.: The checkdigit is 11 minus the sum from step 3. Is the difference 10, the number won't be taken. If the difference is 11, the checkdigit is 0.

METHODS

is_valid($number): Returns true only if $number consists solely of numbers and the rightmost digit is a valid check digit according to the algorithm given above.
Returns false otherwise,
complete($number): The check digit for $number is computed and appended to the end of $number.
Returns the complete number with check digit or '' if $number does not consist solely of digits, hyphens and spaces.
basenumber($number): Returns the basenumber of $number if $number has a valid check digit.
Return '' otherwise.
checkdigit($number): Returns the check digits of $number if $number has valid check digits.
Return '' otherwise.

EXPORT

None by default.

AUTHOR

Mathias Weidner, "<mamawe@cpan.org>"