CheckDigits::M11_017(3pm)				User Contributed Perl Documentation				 CheckDigits::M11_017(3pm)

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.

       2.  The sum of all products is computed.

       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>

SEE ALSO

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

perl v5.10.0							    2008-05-17						 CheckDigits::M11_017(3pm)