NAME

CheckDigits::M97_001 - compute check digits for VAT Registration Number (BE)

SYNOPSIS

  use Algorithm::CheckDigits;

  $ustid = CheckDigits('ustid_be');

  if ($ustid->is_valid('136695962')) {
        # do something
  }

  $cn = $ustid->complete('1366959');
  # $cn = '136695962'

  $cd = $ustid->checkdigit('136695962');
  # $cd = '62'

  $bn = $ustid->basenumber('136695962');
  # $bn = '1366959'

DESCRIPTION

ALGORITHM

1. The whole number (without checksum) is taken modulo 97.
2. The checksum is difference of the remainder from step 1 to 97.

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 checkdigits of $number if $number has a valid check digit.

Return '' otherwise.

EXPORT

None by default.

AUTHOR

Mathias Weidner, <mathias@weidner.in-bad-schmiedeberg.de>

SEE ALSO

perl, CheckDigits, www.pruefziffernberechnung.de.