NAME¶
CheckDigits::M11_008 - compute check digits for VAT Registration Number (DK)
SYNOPSIS¶
use Algorithm::CheckDigits;
$ustid = CheckDigits('ustid_dk');
if ($ustid->is_valid('13585628')) {
# do something
}
$cn = $ustid->complete('1358562');
# $cn = '13585628'
$cd = $ustid->checkdigit('13585628');
# $cd = '8'
$bn = $ustid->basenumber('13585628');
# $bn = '1358562';
DESCRIPTION¶
ALGORITHM¶
- 1.
- Beginning left every digit is weighted with 2, 7, 6, 5, 4,
3, 2, 1
- 2.
- The weighted digits are added.
- 3.
- The sum from step 2 is taken modulo 11.
- 4.
- The number is valid if the sum from step 3 is zero
(0).
METHODS¶
- is_valid($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 '' if $number is valid.
Return undef otherwise.
EXPORT¶
None by default.
AUTHOR¶
Mathias Weidner, <mathias@weidner.in-bad-schmiedeberg.de>
SEE ALSO¶
perl, CheckDigits,
www.pruefziffernberechnung.de,