CUSIPs are a 9-digit alphanumeric code for uniquely identifying a financial security. https://en.wikipedia.org/wiki/CUSIP They were invented in the 1964, and given the reliability of data transm...

There are lots of implementations for validating Luhn checksums but very few for generating them. I've come across this one however in my tests it has revealed to be buggy and I don't understand th...

I am trying to reverse engineer an algorithm used to generate a check digit. Numbers are 8 digits long and the last digit is the check digit. I have thousands of valid numbers to test it on. I h...

Note: I originally posted this to Information Security, but I'm starting to think it might be more relevant here as it's really about determining what I should do with a request rather than securin...

I'd like to use the Damm algorithm to generate check digits for codes with a 32-character alphabet. The algorithm itself is easily applied to any base (except 2 or 6). The difficulty is the necessa...

According to the chart here: http://www.idautomation.com/barcode-faq/code-128/ This character: Ë equates to the value 103. Yet this code: string barcode = textBoxRawCode128.Text.Trim(); . ....