---
name: "Algorithm::CheckDigits::M11_009"
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::M11_009"
---

# Algorithm::CheckDigits::M11\_009(3pm)

compute check digits NRIC (SG)

## NAME

CheckDigits::M11\_009 - compute check digits NRIC (SG)

## SYNOPSIS

```
  use Algorithm::CheckDigits;
  $nric = CheckDigits('nric_sg');
  if ($nric->is_valid('S1234567D')) {
        # do something
  }
  $cn = $nric->complete('S1234567');
  # $cn = 'S1234567D'
  $cd = $nric->checkdigit('S1234567D');
  # $cd = 'D'
  $bn = $nric->basenumber('S1234567D');
  # $bn = 'S1234567';
```

## DESCRIPTION

### ALGORITHM

- 1\.

  Beginning left every digit is weighted with 2, 7, 6, 5, 4, 3, 2

- 2\.

  The weighted digits are added.

- 3\.

  The sum from step 2 is taken modulo 11.

- 4\.

  The checkdigit is 11 minus the sum from step 3 converted to a character according to the following table:

  ```
    @cd = ('','A','B','C','D','E','F','G','H','I','Z','J', );
  ```

### METHODS

- is\_valid($number)

  Returns true only if `$number` consists of seven digits (optional preceded by a letter out of 'F', 'G', 'S', 'T') followed by a valid letter according to the algorithm given above.

  Returns false otherwise,

- complete($number)

  The check letter 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 and letters.

- basenumber($number)

  Returns the basenumber of `$number` if `$number` has a valid check digit.

  Return '' otherwise.

- checkdigit($number)

  Returns '' if `$number` is valid.

  Return undef otherwise.

### EXPORT

None by default.

## AUTHOR

Mathias Weidner, `"<mamawe@cpan.org>"`

## SEE ALSO

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