---
name: "Algorithm::CheckDigits::M23_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::M23_001"
---

# Algorithm::CheckDigits::M23\_001(3pm)

compute check digits for DNI (ES)

## NAME

CheckDigits::M23\_001 - compute check digits for DNI (ES)

## SYNOPSIS

```
  use Algorithm::CheckDigits;
  $dni = CheckDigits('dni_es');
  if ($dni->is_valid('54362315K')) {
        # do something
  }
  $cn = $dni->complete('54362315');
  # $cn = '54362315K'
  $cd = $dni->checkdigit('54362315K');
  # $cd = 'K'
  $bn = $dni->basenumber('54362315K');
  # $bn = '54362315'
```

## DESCRIPTION

### ALGORITHM

- 1\.

  The checkdigit is the whole number taken modulo 23 and coded according to a keytable.

### 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*.