I looked at the new checkins for fast MatMatSym. It looks to me like you want a data structure that has
a) O(N) space, where N is the number of entries b) fast insert c) fast traversal It seems like the best data structure of this is http://en.wikipedia.org/wiki/Y-fast_trie It has O(N) space, and O(log log M) where M is the maximum key size. It basically uses prefix compression on the bitwise representation of the keys, so that runs of consecutive integers are handled well. So far, I cannot find any free implementations. Matt -- What most experimenters take for granted before they begin their experiments is infinitely more interesting than any results to which their experiments lead. -- Norbert Wiener -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://lists.mcs.anl.gov/pipermail/petsc-dev/attachments/20111219/4df3e15e/attachment.html>
