SYNOPSIS
use Algorithm::CheckDigits;
$ustid = CheckDigits('esr5_ch');
if ($ustid->is_valid('123456786')) {
# do something
}
$cn = $ustid->complete('12345678');
# $cn = '123456786'
$cd = $ustid->checkdigit('123456786');
# $cd = '6'
$bn = $ustid->basenumber('123456786');
# $bn = '12345678';
DESCRIPTION
ALGORITHM
- 1.
- Beginning left every digit is weighted with 7,9,10,5,8,4,2.
- 2.
- The weighted digits are added.
- 3.
- The sum from step 2 is taken modulo 11.
- 4.
- The checkdigit is 11 minus the sum from step 3. Is the difference 10, the number won't be taken. If the difference is 11, the checkdigit is 0.
METHODS
- is_valid($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 the check digits of $number if $number has valid check
digits.
Return '' otherwise.