NAME

CheckDigits::M07_001 - compute check digits modulo 7 method 1

SYNOPSIS

  use Algorithm::CheckDigits;

  $m001 = CheckDigits('m001');

  if ($m001->is_valid('1234567892')) {
        # do something
  }

  $cn = $m001->complete('123456789');    # $cn = '1234567892'

  $cd = $m001->checkdigit('1234567892'); # $cd = '2'

  $bn = $m001->basenumber('1234567892'); # $bn = '123456789'

DESCRIPTION

ALGORITHM

1.: All digits are added.
2.: All digits at even positions are added.
3.: The sum of step 1 and 2 is taken modulo 7.
4.: This is the check digit.

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 undef if $number does not consist solely of digits.
basenumber($number): Returns the basenumber of $number if $number has a valid check digit.
Return undef otherwise.
checkdigit($number): Returns the check digit belonging to $number or undef if $number does not consist solely of digits.

EXPORT

None by default.

AUTHOR

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