NAME

CheckDigits::M10_005 - compute check digits for Deutsche Post Identcode/Leitcode (DE)

SYNOPSIS

  use Algorithm::CheckDigits;

  $ic = CheckDigits('identcode_dp');

  if ($ic->is_valid('21.802 580.906 6')) {
        # do something
  }

  $cn = $ic->complete('21.802 580.906');
  # $cn = '21.802 580.9066'

  $cd = $ic->checkdigit('21.802 580.906 6');
  # $cd = '6'

  $bn = $ic->basenumber('21.802 580.906 6');
  # $bn = '21.802 580.906'
  

DESCRIPTION

ALGORITHM

1. Beginning left all numbers are weighted alternatively 4 and 9.

2. The sum of all products is computed.

3. The sum of step 3 ist taken modulo 10.

4. The check digit is the difference between 10 and the number from step 3.

METHODS

is_valid($number)

Returns true only if $number consists solely of numbers and the last 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 concatenated to the end of $number.

Returns the complete number with check digit or '' if $number does not consist solely of digits and spaces.

basenumber($number)

Returns the basenumber of $number if $number has a valid check digit.

Return '' otherwise.

checkdigit($number)

Returns the checkdigit of $number if $number has a valid check digit.

Return '' otherwise.

EXPORT

None by default.

AUTHOR

Mathias Weidner, <mamawe@cpan.org>

SEE ALSO

perl, CheckDigits, www.pruefziffernberechnung.de.