Algorithm::CheckDigits::M11_009 (3pm)

  use Algorithm::CheckDigits;

  $nric = CheckDigits('nric_sg');

  if ($nric->is_valid('S1234567D')) {
        # do something
  }

  $cn = $nric->complete('S1234567');
  # $cn = 'S1234567D'

  $cd = $nric->checkdigit('S1234567D');
  # $cd = 'D'

  $bn = $nric->basenumber('S1234567D');
  # $bn = 'S1234567';

\s-1ALGORITHM\s0

1.

Beginning left every digit is weighted with 2, 7, 6, 5, 4, 3, 2

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 converted to a character according to the following table: @cd = ('','A','B','C','D','E','F','G','H','I','Z','J', );

\s-1METHODS\s0

is_valid($number)

Returns true only if $number consists solely of numbers and hyphens and the two digits in the middle are valid check digits according to the algorithm given above. Returns false otherwise,

complete($number)

The check digit for $number is computed and inserted into the middle 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 '' if $number is valid. Return undef otherwise.

\s-1EXPORT\s0

None by default.

Mathias Weidner, <[email protected]>

perl, CheckDigits, www.pruefziffernberechnung.de,