Provided by: libalgorithm-checkdigits-perl_0.50-1_all #### NAME

```       CheckDigits::M11_017 - compute check digits for EC-No, EINECS, ELINCS

```

#### SYNOPSIS

```         use Algorithm::CheckDigits;

\$ecno = CheckDigits('ecno');

if (\$ecno->is_valid('200-236-6')) {
# do something
}

\$cn = \$ecno->complete('200-236-');
# \$cn = '200-236-6'

\$cd = \$ecno->checkdigit('200-236-6');
# \$cd = '6'

\$bn = \$ecno->basenumber('200-236-6');
# \$bn = '200-236-'

```

#### DESCRIPTION

```   ALGORITHM
1.  From left to right all digits are multiplied with their position in the sequence.

3.  The sum of step 2 is taken modulo 11.

The checkdigit is the last digit of the result.

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

```

#### SEEALSO

```       perl, CheckDigits, http://en.wikipedia.org/wiki/EC-No.
```