On 6/14/10 6:19 PM, Florent Hivert wrote:
So basically you still want to writeA = copy(B) # create a semantic copy but no actual copy is done A[1,2] = 4 # the copy is triggered... An since the actual entries of the matrix are stored in an attributes called _entries, two different matrix objects can have share the same entries so that the matrix object is doing the indirection for you. So this sound good and not very hard to do...
Hmm. It would be interesting to see if you could have sparse matrices where it was COW per-entry, rather than per-matrix (i.e., A[1,2]=3 would just add an entry, an overlay, sort of, on the original data. I can see some performance issues, but maybe the space savings would be worth it.
Anyways, these are interesting ideas. Jason -- To post to this group, send an email to sage-devel@googlegroups.com To unsubscribe from this group, send an email to sage-devel+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-devel URL: http://www.sagemath.org
