# Algorithm::CheckDigits::M11_016.3pm

Langue: en

Autres versions - même langue

Version: 2009-11-20 (fedora - 01/12/10)

Section: 3 (Bibliothèques de fonctions)

# Sommaire

## NAME

CheckDigits::M11_016 - compute check digits vor VAT Registration Number (PL)

## SYNOPSIS

```   use Algorithm::CheckDigits;

\$nip = CheckDigits('nip');

if (\$nip->is_valid('8567346215')) {
# do something
}

\$cn = \$nip->complete('856734621');
# \$cn = '8567346215'

\$cd = \$nip->checkdigit('856734621');
# \$cd = '5'

\$bn = \$nip->basenumber('8567346215');
# \$bn = '856734621';

```

## DESCRIPTION

### ALGORITHM

1.
Beginning left every digit is weighted with 6, 5, 7, 2, 3, 4, 5, 6, 7
2.
3.
The sum from step 2 is taken modulo 11.
4.
The checkdigit is 11 minus the sum from step 3. Is the difference 10, the number won't be taken. If the difference is 11, the checkdigit is 0.

### METHODS

is_valid(\$number)
Returns true only if \$number consists solely of numbers and the rightmost 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 appended to the end 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.

None by default.