Man pages sections > man3 > Algorithm::CheckDigits::M11_009

# CheckDigits::M11_009 - compute check digits NRIC (SG)

 CheckDigits::M11_009(3pm) User Contributed Perl Documentation CheckDigits::M11_009(3pm)

## 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 solely of numbers and hyphens and the two digits in the middle are valid check digits according to the algorithm given above.

Returns false otherwise,
complete(\$number)
The check digit for \$number is computed and inserted into the middle 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 '' if \$number is valid.

Return undef otherwise.

None by default.