SYNOPSIS
use Algorithm::CheckDigits;
$ahv = CheckDigits('ahv_ch');
if ($ahv->is_valid('123.45.678.113')) {
# do something
}
$cn = $ahv->complete('123.45.678.11');
# $cn = '123.45.678.113'
$cd = $ahv->checkdigit('123.45.678.113');
# $cd = '3'
$bn = $ahv->basenumber('123.45.678.113');
# $bn = '123.45.678.11';
DESCRIPTION
ALGORITHM
- 1.
- Beginning left every digit is weighted with 5,4,3,2,7,6,5,4,3,2.
- 2.
- The weighted digits are added.
- 3.
- The sum from step 2 is taken modulo 11.
- 4.
- The checkdigit is 11 minus the sum from step 3. Is the difference 10, the number won't be taken. If the difference is 11, the checkdigit is 0.
METHODS
- is_valid($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.