This is cool. Kind of makes me wish my sparse matrices were larger than 300x300. I'll experiment with it anyway.
On Saturday, December 27, 2014 4:56:55 AM UTC-5, Mike Anderson wrote: > > Here is a little belated Christmas present for Clojure data aficionados: > > ;; setup > (use 'clojure.core.matrix) > (set-current-implementation :vectorz) > > ;; create a big sparse matrix with a trillion elements (initially zero) > (def A (new-sparse-array [1000000 1000000])) > > ;; we are hopefully smart enough to avoid printing the whole array! > A > => #<SparseRowMatrix Large matrix with shape: [1000000,1000000]> > > ;; mutable setter operations supported so that you can set individual > sparse elements > (dotimes [i 1000] > (mset! A (rand-int 1000000) (rand-int 1000000) (rand-int 100))) > > ;; all standard core.matrix operations supported > (esum A) > => 50479.0 > > ;; efficient addition > (time (add A A)) > => "Elapsed time: 12.849859 msecs" > > ;; matrix multiplication / inner products actually complete in sensible > time > ;; (i.e. much faster than than the usual O(n^3) which might take a few > thousand years) > (time (mmul A (transpose A))) > => "Elapsed time: 2673.085171 msecs" > > > Some nice things to note about the implementation: > - Everything goes through the core.matrix API, so your code won't have to > change to use sparse matrices :-) > - Sparse matrices are 100% interoperable with non-sparse (dense) matrices > - Sparse arrays are fully mutable. Management of storage / indexing > happens automatically > - It isn't just matrices - you can have sparse vectors, N-dimensional > arrays etc. > - Code is pure JVM - no native dependencies to worry about > > This is all still very much alpha - so any comments / patches / more > rigorous testing much appreciated! > > > > -- You received this message because you are subscribed to the Google Groups "Clojure" group. To post to this group, send email to clojure@googlegroups.com Note that posts from new members are moderated - please be patient with your first post. To unsubscribe from this group, send email to clojure+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/clojure?hl=en --- You received this message because you are subscribed to the Google Groups "Clojure" group. To unsubscribe from this group and stop receiving emails from it, send an email to clojure+unsubscr...@googlegroups.com. For more options, visit https://groups.google.com/d/optout.
