I have obtained the CRC-64 code used in the SWISS-PROT genetic database: ftp://ftp.ebi.ac.uk/pub/software/swissprot/Swissknife/SPcrc.tar.gz (Thanks go to Henning Hermjakob <[EMAIL PROTECTED]> of the European Bioinformatics Institute.) From the README: The code in this package has been derived from the BTLib package obtained from Christian Iseli <[EMAIL PROTECTED]>. From his mail: The reference is: W. H. Press, S. A. Teukolsky, W. T. Vetterling, and B. P. Flannery, "Numerical recipes in C", 2nd ed., Cambridge University Press. Pages 896ff. The generator polynomial is x64 + x4 + x3 + x1 + 1. Choosing a good polynomial is considered a black art. A good tutorial on CRC practice is at http://www.repairfaq.org/filipg/LINK/F_crc_v3.html and there's a clear exposition of the theory in Tanenbaum's "Computer Networks". Note that initialization is important, and often neglected: one quality to check is, does a block of all zeroes, and a zero CRC, come out as an error? Nathan Myers [EMAIL PROTECTED]
