NAME
CheckDigits::M11_017 - compute check digits for EC-No, EINECS, ELINCS
SYNOPSIS
use Algorithm::CheckDigits;$ecno = CheckDigits('ecno');if ($ecno->is_valid('200-236-6')) {# do something}$cn = $ecno->complete('200-236-');# $cn = '200-236-6'$cd = $ecno->checkdigit('200-236-6');# $cd = '6'$bn = $ecno->basenumber('200-236-6');# $bn = '200-236-'
DESCRIPTION
ALGORITHM
- 1.
-
From left to right all digits are multiplied with their position in the sequence.
- 2.
-
The sum of all products is computed.
- 3.
-
The sum of step 2 is taken modulo 11.
The checkdigit is the last digit of the result.
METHODS
- is_valid($number)
-
Returns true only if
$numberconsists solely of numbers and the last digit is a valid check digit according to the algorithm given above.Returns false otherwise,
- complete($number)
-
The check digit for
$numberis computed and concatenated to the end of$number.Returns the complete number with check digit or '' if
$numberdoes not consist solely of digits and spaces.
- basenumber($number)
-
Returns the basenumber of
$numberif$numberhas a valid check digit.Return '' otherwise.
- checkdigit($number)
-
Returns the checkdigit of
$numberif$numberhas a valid check digit.Return '' otherwise.
EXPORT
None by default.
AUTHOR
Mathias Weidner, "<[email protected]>"
SEE ALSO
perl, CheckDigits, http://en.wikipedia.org/wiki/EC-No.