On Wed, May 27, 2009 at 1:49 AM, Simon King <simon.k...@uni-jena.de> wrote: > > Hi! > > The mission statement or our project on cohomology rings says that we > should make a data base publically available. It should in some way be > available for Sage (say, as an optional/experimental package), but I > wonder if it is possible. > > 1) An spkg just with our programs would be about 460 MB. I think this > is ok. But a gzipped tar ball of our results (forming the data of a > data base) would be 20 GB for about 2500 cohomology rings. Is this too > much for inclusion into the spkg? I guess it is.
One of the first Sage optional spkg's I ever made is 2 TB (terabytes!). You could have your 20GB spkg listed here: http://sagemath.org/sagedb/ > > But how else could I provide the data? Perhaps I can keep it on some > web site (on sage.math?), for downloading the data of single > cohomology rings on demand? You could certainly also do that. Just put it in a directory in your home directory. I have directories like that: http://sage.math.washington.edu/home/wstein/db/modsym/data/ > > 2) Having the data is one thing. Having a relational data base is a > different thing. > What I can do: > Given the address (q,n) of a finite p-group in the Small Groups > Library, my cohomology constructor first tries to find the cohomology > data stored on disk, and if it fails then it creates the ring from > scratch. > What I want to be able to do: > The data base should be able to return, say, a list of all known > cohomology rings of depth 2, or a list of all cohomology rings with a > given Poincare series. > > I guess that those things are doable with sqlalchemy, but perhaps you > have a different/better suggestion. Such a database would be tiny. Just store the depth and poincare series and some pointer to each cohomology ring, which you could store on sage.math. > And I would appreciate a direct pointer to manual pages that explain > how to create a data base, given a function that returns some object > to a given key, so that the data base relates the key with certain > special properties (depth, Poincare series,...) of the returned > objects. I would just copy an existing an example. You might also look at the sqlalchemy web page if you want to make a relational database. William > > Best regards, > Simon > > > > -- William Stein Associate Professor of Mathematics University of Washington http://wstein.org --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
