CheckDigits::M11_013(3User Contributed Perl DocumentatiCheckDigits::M11_013(3)NAME
CheckDigits::M11_013 - compute check digits for VAT Registration Number
(GR)
SYNOPSIS
use Algorithm::CheckDigits;
$ustid = CheckDigits('ustid_gr');
if ($ustid->is_valid('123456783')) {
# do something
}
$cn = $ustid->complete('12345678');
# $cn = '123456783'
$cd = $ustid->checkdigit('123456783');
# $cd = '3'
$bn = $ustid->basenumber('123456783');
# $bn = '12345678';
DESCRIPTION
ALGORITHM
1. Beginning right with the digit before the checkdigit all digits are
weighted with 2 ** position. I. e. the last digit is multiplied
with 2, the next with 4, then 8 and so on.
2. The weighted digits are added.
3. The sum from step 2 is taken modulo 11.
4. If the sum from step 3 is greater than 9, the check sum is 0 else
it is the sum itself.
METHODS
is_valid($number)
Returns true only if $number consists solely of numbers and the
rightmost digit is a valid check digit according to the algorithm
given above.
Returns false otherwise,
complete($number)
The check digit for $number is computed and appended to the end of
$number.
Returns the complete number with check digit or '' if $number does
not consist solely of digits.
basenumber($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.
EXPORT
None by default.
AUTHOR
Mathias Weidner, <mathias@weidner.in-bad-schmiedeberg.de>
SEE ALSO
perl, CheckDigits, www.pruefziffernberechnung.de,
perl v5.14.1 2009-11-20 CheckDigits::M11_013(3)
