---
name: "Algorithm::CheckDigits::M43_001"
section: "3pm"
platform: "linux"
package: "libalgorithm-checkdigits-perl"
version: "1.3.6-2"
release: "Debian 13 (Trixie)"
platforms: ["linux"]
url: "https://new.carta.tech/Algorithm::CheckDigits::M43_001"
---

# Algorithm::CheckDigits::M43\_001(3pm)

compute check digits for Code-39

## NAME

CheckDigits::M43\_001 - compute check digits for Code-39

## SYNOPSIS

```
  use Algorithm::CheckDigits;
  $c39 = CheckDigits('code_39');
  if ($c39->is_valid('AB-123K')) {
        # do something
  }
  $cn = $c39->complete('AB-123');
  # $cn = 'AB-123K'
  $cd = $c39->checkdigit('AB-123K');
  # $cd = 'K'
  $bn = $c39->basenumber('AB-123K');
  # $bn = 'AB-123'
```

## DESCRIPTION

### ALGORITHM

- 1\.

  After replacing all non numeric letters with their respective values, the sum of all numbers is computers

- 2\.

  The checkdigit is the sum from step 1 taken modulo 43.

### 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, `"<mamawe@cpan.org>"`

## SEE ALSO

perl, CheckDigits, *www.pruefziffernberechnung.de*.