Implement or wrap Braid Groups

[mabshoff]

This looks very much like a wish list item. Moved.

Cheers,

Michael

[wdj]

BTW, in gap_packages there is a GPL'd package called braid that might help here. It was packaged before GPLv3 came out (I actually did the packaging but did not write any of the code).

[kcrisman]

Incidentally, apparently the braid package is now autoloaded, though it doesn't seem to be used anywhere. This is improperly documented in interfaces/gap.py, though:

    The packages sonata, guava, factint, gapdoc, grape, design, toric,
    and laguna are loaded in all cases before the workspace is saved,
    if they are available.

    g = Gap(use_workspace_cache=False, max_workspace_size=None)
    for pkg in ['ctbllib', 'sonata', 'guava', 'factint', \
                'gapdoc', 'grape', 'design', \
                'toric', 'laguna', 'braid']:   # NOTE: Do *not* autoload hap - it screws up PolynomialRing(Rationals,2)
        try:
            g.load_package(pkg, verbose=verbose)

[wdj]

Replying to kcrisman:

Incidentally, apparently the braid package is now autoloaded, though it doesn't seem to be used anywhere. This is improperly documented in interfaces/gap.py, though:

    The packages sonata, guava, factint, gapdoc, grape, design, toric,
    and laguna are loaded in all cases before the workspace is saved,
    if they are available.

    g = Gap(use_workspace_cache=False, max_workspace_size=None)
    for pkg in ['ctbllib', 'sonata', 'guava', 'factint', \
                'gapdoc', 'grape', 'design', \
                'toric', 'laguna', 'braid']:   # NOTE: Do *not* autoload hap - it screws up PolynomialRing(Rationals,2)
        try:
            g.load_package(pkg, verbose=verbose)

I think this problem with HAP was fixed long ago.

Also, I think I had to repackage braid recently because of some loading problems it had. I don't remember the details. Maybe it was because of a problem with gap 4.4.12 and since we use 4.4.10, it is not an issue?

[kcrisman]

Looks like this is now much further along at #12339.