NAME¶
CheckDigits::MXX_001 - compute check digits for PA (DE)
SYNOPSIS¶
use Algorithm::CheckDigits;
$pa = CheckDigits('pa_de');
if ($pa->is_valid('2406055684D<<6810203<0705109<6')) {
# do something
}
$cn = $pa->complete('240605568_D<<681020_<070510_<_');
# $cn = '2406055684D<<6810203<0705109<6'
$cd = $pa->checkdigit('2406055684D<<6810203<0705109<6');
# $cd = '6'
$bn = $pa->basenumber('2406055684D<<6810203<0705109<6');
# $bn = '240605568_D<<681020_<070510_<_'
DESCRIPTION¶
ALGORITHM¶
- 1.
- Beginning left all digits are weighted with
7,3,1,7,3,1,...
- 2.
- The sum of those products is computed.
- 3.
- The checksum is the last digit of the sum from step 2
(modulo 10).
- 4.
- Step 1 to 3 is performed for every part of the number and
for all 3 parts including the particular checkdigit to compute the total
checksum.
METHODS¶
- is_valid($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>
THANKS¶
Aaron W. West pointed me to a fault in the computing of the check digit.
SEE ALSO¶
perl, CheckDigits,
www.pruefziffernberechnung.de,
www.export911.com/e911/coding/upcChar.htm,
www.adams1.com/pub/russadam/upccode.html,
http://www.upcdatabase.com.