CheckDigits::M23_002(3User Contributed Perl DocumentatiCheckDigits::M23_002(3)NAME
CheckDigits::M23_002 - compute check digits for VAT Registration Number
(IE)
SYNOPSIS
use Algorithm::CheckDigits;
$dni = CheckDigits('ustid_ie');
if ($dni->is_valid('8473625E')) {
# do something
}
$cn = $dni->complete('8473625');
# $cn = '8473625E'
$cd = $dni->checkdigit('8473625E');
# $cd = 'E'
$bn = $dni->basenumber('8473625E');
# $bn = '8473625'
DESCRIPTION
ALGORITHM
1. Beginning right all digits are weighted with their position in the
number (i.e. the number left from the check digit is multiplied
with 2, the next with 3 and so on).
2. All products are added.
3. The check digit is the sum from step 2 modulo 23. This number is
expressed as the corresponding letter from the alphabet where A-V
correspond to 1-22 and W stands for check digit 0.
METHODS
is_valid($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.
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::M23_002(3)
