On Wed, Feb 11, 2009 at 6:52 AM, Simon King <k...@mathematik.uni-jena.de> wrote: > > Dear sage developers, > > some people, including myself, believe that Sage should contain more > tools for topology. E.g., there was a thread > http://groups.google.com/group/sage-devel/browse_thread/thread/5bd11c7e9fe08e4c/6ba64c41dd86770e?lnk=gst&q=simplicial+complexes#6ba64c41dd86770e > about simplicial complexes and their homology. > > John Palmieri has sent a post to some algebraic topology list (https:// > lists.lehigh.edu/mailman/listinfo/algtop-l), pointed the people to > Sage and asked for contribution. Thank you, John!
I very much hope Algebraic Topology will be a theme at Sage Days 15: http://wiki.sagemath.org/days15 Simon -- any chance you will be able to go to that? > Being subscriber of that list, I added that one way to contribute is > to point us to existing software packages. So far, there was one > answer (concerning "plex", see below). > > My question: How should the work on inclusion of topology software be > organized? Should one open a single trac ticket (essentially > complaining that there is not enough topology around), on which > suggestions for inclusions are collected? No! A wiki.sagemath.org page and email discussion would be much better for that. > Or should the collection be > on this thread, with one separate ticket for each suggestion? Yes. > Here are three suggestions: > 1. Simplicial complexes / Homology (see thread above) > I asked Frank Lutz, and he said that Polymake had a module 'topaz' > that can compute homology. However, in a recent Polymake upgrade, > topaz was removed from the distribution, due to some compiler problem. > So, it might make sense to wait for on upgrade of topaz. > > 2. SnapPea > SnapPea is a program for creating and studying hyperbolic 3-manifolds > (http://www.geometrygames.org/SnapPea-old/index.html). It seems to be > widely used by computational topologists. AFAIK it can deal with ideal > triangulations, compute volume, has a census of hyperbolic manifolds, > can also work with hyperbolic knots, etc. > If I understand correctly, it is under GNU GPL and may be used as a > Python module. A longtime Sage user -- Nathan Dunfield -- I think wrote the Python interface, and uses SnapPea from Sage for his research. > 3. Plex (suggestion of Ryan Lewis from the above-mentioned topology > list) > Plex is a software package for computing persistent homology of finite > simplicial complexes, often generated from point cloud data (http:// > comptop.stanford.edu/programs/jplex/index.html). > > 4. I found a link to a list of topology related software: > http://www.math.uiuc.edu/~nmd/computop/ > Some of these might be interesting. > > I am not sure if Plex really is an option for Sage. Previous versions > were written for Matlab. The current version is written in Java and > can also run in a standalone mode, using an integrated Java > interpreter, called Beanshell. Dunno if that works for Sage. It's an option as an optional package. I doubt it will be standard, but I doubt anything big will be added to standard sage anytime _this_ year due to porting being the number one goal. But that shouldn't stop anybody from writing good interfaces between Sage and other software. There's no a priori reason that there shouldn't be an excellent Sage <--> X interface for all math software X. -- William --~--~---------~--~----~------------~-------~--~----~ To post to this group, send email to sage-devel@googlegroups.com To unsubscribe from this group, send email to sage-devel-unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URLs: http://www.sagemath.org -~----------~----~----~----~------~----~------~--~---
