Algorithm::CheckDigits::M11_004 (3pm)

  use Algorithm::CheckDigits;

  $cpf = CheckDigits('cpf');

  if ($cpf->is_valid('043.033.407-90')) {
        # do something
  }

  $cn = $cpf->complete('043.033.407-');
  # $cn = '043.033.407-90'

  $cd = $cpf->checkdigit('043.033.407-90');
  # $cd = '90'

  $bn = $cpf->basenumber('043.033.407-90');
  # $bn = '043.033.407-'

\s-1ALGORITHM\s0

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. a) If the result is 0 or 1 the checkdigit is 0 b) otherwise the checkdigit is 11 minus the result.

4.

The first checkdigit is appended to the number and step 1 to 3 are repeated.

\s-1METHODS\s0

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.

\s-1EXPORT\s0

None by default.

Mathias Weidner, <[email protected]>

perl, CheckDigits, www.pruefziffernberechnung.de.