Weight enumerators of duadic and quadratic residue codes

Abstract

We compute the weight enumerators of various quadratic residue (QR) codes over F/sub 2/ and F/sub 3/, together with certain codes of related families like the duadic codes. We use a parallel algorithm to find the number of codewords of a given (not too high) weight, from which we deduce by usual classical methods for selfdual and isodual codes over F/sub 2/ and F/sub 3/ their associated, previously unknown, weight enumerators. We compute weight enumerators for lengths as high as 152 for binary codes (except for n=138 for which one lacks the number of codewords of weight 34) and 84 for ternary codes.