SYNOPSIS
use Algorithm::CheckDigits;
$bb = CheckDigits('blutbeutel');
if ($bb->is_valid('2761011234567893')) {
# do something
}
$cn = $bb->complete('276101123456789');
# $cn = '2761011234567893'
$cd = $bb->checkdigit('2761011234567893');
# $cd = '3'
$bn = $bb->basenumber('2761011234567893');
# $bn = '276101123456789';
DESCRIPTION
ALGORITHM
- 1.
- Start with values P = 10, S = 0.
- 2.
-
Beginning left you do the following for all digits
-
- 1.
- S = (P + digit) modulo 10
- 2.
- If S is 0 then S = 10.
- 3.
- P = (2 * S) modulo 11
-
- 3.
- The check digit is (11 - P) modulo 10.
METHODS
- is_valid($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.