There are two common algorithms, one which uses the 'X' and one that doesn't. Basically the one that uses the 'X' takes a weighted sum of the digits and divides it by 11. The remainder is the check digit. If the remainder is 10, then the digit is 'X'. 'X' as in the Roman numeral.
Example: number: 123456 weights: 153872 product: 1(10)9(32)(35)(12) sum: 99 remainder / check digit: 0 You will need to find out the weights they use. Also there is a variant that first takes the remainder off 10, and if applied to the above example, the check digit will be 'X'. ----- Original Message ----- From: "Mark Howard" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Monday, February 23, 2004 5:42 PM Subject: [DUG] Check Digit > Hi > > We have a client who is using a Docket numbering system that incorporates a check > "digit" at the end. The check "digit" is 0-9 or x. > > thus: 399079x, 3990800, 3990811 > > The purpose of the check digit is to verify the validity of the digits in the root number > - a sequence of digits in the root number can have only one valid check digit. > > I suspect that this is a common device, and if it is, I am wanting to know what the > algorithim is to determine the check digit from the root number. > > Anyone any ideas? > > Thanks > > Mark > _______________________________________________ > Delphi mailing list > [EMAIL PROTECTED] > http://ns3.123.co.nz/mailman/listinfo/delphi > _______________________________________________ Delphi mailing list [EMAIL PROTECTED] http://ns3.123.co.nz/mailman/listinfo/delphi
