Provided by: libalgorithm-checkdigits-perl_0.50-1_all

**NAME**

CheckDigits::MBase_003 - compute check digits for SICI (Serial Item and Contribution Identifier)

**SYNOPSIS**

use Algorithm::CheckDigits; $sici = CheckDigits('sici'); if ($sici->is_valid('0784-8679(20040308)6:<138>2.0.TX;2-H')) { # do something } $cn = $sici->complete('0784-8679(20040308)6:<138>2.0.TX;2-'); # $cn = '0784-8679(20040308)6:<138>2.0.TX;2-H' $cd = $sici->checkdigit('0784-8679(20040308)6:<138>2.0.TX;2-H'); # $cd = 'H' $bn = $sici->basenumber('0784-8679(20040308)6:<138>2.0.TX;2-H'); # $bn = '0784-8679(20040308)6:<138>2.0.TX;2-';

**DESCRIPTION**

ALGORITHM0 In the string describing the number all letters (A-Z) are replaced with numbers 10-35 accordingly. All other non-numbers are replaced by 36. 1 Beginning right the numbers at all odd positions are added. 2 The sum from step 1 is multiplied by 3. 3 Beginning right the numbers at all even positions are added. 4 The sums from step 2 and 3 are added. 5 The sum from step 4 is taken modulo 37. 6 The checksum is 37 minus the sum from step 5 where numbers from 10 to 35 are represented by 'A' to 'Z' accordingly and 36 is represented by '#'.METHODSis_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 the check digits of $number if $number has valid check digits. Return '' otherwise.EXPORTNone by default.

**AUTHOR**

Mathias Weidner, <mathias@weidner.in-bad-schmiedeberg.de>

**SEE** **ALSO**

perl, CheckDigits,www.pruefziffernberechnung.de,http://sunsite.berkeley.edu/SICI/sici.pdf