Algorithm::CheckDigits::M10_0033pm
Compute check digits for ismn
Usage
use Algorithm::CheckDigits;$ismn = CheckDigits('ismn');if ($ismn->is_valid('M-345-24680-5')) {# do something}$cn = $ismn->complete('M-345-24680');# $cn = 'M-345-24680-5'$cd = $ismn->checkdigit('M-345-24680-5');# $cd = '5'$bn = $ismn->basenumber('M-345-24680-5');# $bn = 'M-345-24680'
Overview
Algorithm
- 1.
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The 'M' as the first number gets the value 3. Beginning left all numbers are weighted alternatively 3 and 1.
- 2.
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The sum of all products is computed.
- 3.
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The sum of step 3 ist taken modulo 10.
- 4.
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The check digit is the difference between 10 and the number from step 3 taken modulo 10.
Methods
- is_valid($number)
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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)
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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)
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Returns the basenumber of
$numberif$numberhas a valid check digit.Return '' otherwise.
- checkdigit($number)
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Returns the checkdigit of
$numberif$numberhas a valid check digit.Return '' otherwise.
Export
None by default.
Releases
9 releases since Debian 5.0 (Lenny); the text changed 3 times.