Hello everybody, I have nothing planned yet, but these days I often think of the different data structures available for graphs (and digraphs) in Sage.
Currently, Sage's default data structure is optimized for a fast "edge test" detection (log n). This is good for some applications, and bad for others. One thing is very important when it comes to (graph) algorithms: the defaut data structure only matters for (sub)-linear algorithms. Indeed, for algorithms of higher complexity it is comparatively cheap to change the data structure, and work on the copy instead. The current default data structure, however, makes it hard to load *large* (> millions of nodes) graphs in memory, for adding an edge is relatively expensive and the data structures wastes quite some memory. For those applications, it would make more sense to have a simpler data structure. Deleting an edge/vertex, however, or testing adjacency between two vertices would be *very* slow. In those case, copying the graph to another (the current default) data structure would be 'required'. If you use graphs in your code, could you tell me if you instensively remove vertices/edges or test adjacency? Or would you prefer to exchange that for a reduced memory cost? Once more: I have nothing planned. Just wondering. And knowing what you think may help. Thanks, Nathann -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at http://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
