isbn10_code, a Fortran90 code which determines the check digit for a 10 digit International Standard Book Number (ISBN10) or reports whether a given ISBN10 is valid.
The information on this web page is distributed under the MIT license.
isbn10_code is available in a C version and a C++ version and a Fortran90 version and a MATLAB version and an Octave version and a Python version.
bank_code, a Fortran90 code which computes the check digit associated with a US Bank Routing Number check digit, or reports whether a 9-digit code is valid.
luhn, a Fortran90 code which computes the Luhn check digit for a string, or validates a string.
upc, a Fortran90 code which determines the check digit for a Uniform Product Code (UPC) or reports whether a given UPC is valid.