SYNOPSIS
use Algorithm::CheckDigits;
$esr = CheckDigits('esr9');
if ($esr->is_valid('123456786')) {
# do something
}
$cn = $esr->complete('12345678');
# $cn = '123456786'
$cd = $esr->checkdigit('123456786');
# $cd = '6'
$bn = $esr->basenumber('123456786');
# $bn = '12345678'
DESCRIPTION
ALGORITHM
- 1.
- Digits are processed left to right. For the first digit applies the balance is 0.
- 2.
- The new balance is taken from the balance table according to the current balance (row) and the digit (column).
- 3.
- The check digit is the difference from the last balance to 10 taken modulo 10.
METHODS
- is_valid($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.