Algorithm::CheckDigits::M11_017(3)

NAME
CheckDigits::M11_017 - compute check digits for EC-No, EINECS, ELINCS

SYNOPSIS
  use Algorithm::CheckDigits;

  $ecno = CheckDigits('ecno');

  if ($ecno->is_valid('200-236-6')) {
        # do something
  }

  $cn = $ecno->complete('200-236-');
  # $cn = '200-236-6'

  $cd = $ecno->checkdigit('200-236-6');
  # $cd = '6'

  $bn = $ecno->basenumber('200-236-6');
  # $bn = '200-236-'

DESCRIPTION

  ALGORITHM

1.  From left to right all digits are multiplied with their position in the sequence.

2.  The sum of all products is computed.

3.  The sum of step 2 is taken modulo 11.

    The checkdigit is the last digit of the result.

  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, http://en.wikipedia.org/wiki/EC-No.