table of contents
CheckDigits::MBase_003(3pm) | User Contributed Perl Documentation | CheckDigits::MBase_003(3pm) |
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'); # $bn = '0784-8679(20040308)6:<138>2.0.TX;2-';
DESCRIPTION¶
ALGORITHM¶
- 0
- In the string describing the number all letters (A-Z) are replaced with numbers 10-35 accordingly. All other non-numbers are replaced by 36.
- 1
- Beginning right the numbers at all odd positions are added.
- 2
- The sum from step 1 is multiplied by 3.
- 3
- Beginning right the numbers at all even positions are added.
- 4
- The sums from step 2 and 3 are added.
- 5
- The sum from step 4 is taken modulo 37.
- 6
- The checksum is 37 minus the sum from step 5 where numbers from 10 to 35 are represented by 'A' to 'Z' accordingly and 36 is represented by '#'.
METHODS¶
- is_valid($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.
EXPORT¶
None by default.AUTHOR¶
Mathias Weidner, <mathias@weidner.in-bad-schmiedeberg.de>SEE ALSO¶
perl, CheckDigits, www.pruefziffernberechnung.de, http://sunsite.berkeley.edu/SICI/sici.pdf2008-05-17 | perl v5.10.0 |