[R] fast matrix-vector multiplication

Hi all, Is there a way to do a matrix multiplication in a faster way? I am making a product of a matrix (composed of a lot of dummy variables) and a vector, and is there any way to make it faster? The simple X %*% y takes too long a time. I know using sparse matrix would help, but don't

Re: [R] fast matrix-vector multiplication

Check out crossprod and the Matrix package (capitalized); there's also a discussion of their speed gains in the R newsletter that should turn up with a search and in the vignette as well. -Gray On Monday, December 14, 2009, parkbomee bbom...@hotmail.com wrote: Hi all, Is there a way to

Re: [R] fast matrix-vector multiplication

GC == Gray Calhoun gray.calh...@gmail.com on Mon, 14 Dec 2009 19:26:44 -0600 writes: GC Check out crossprod and the Matrix package (capitalized); there's also GC a discussion of their speed gains in the R newsletter that should turn GC up with a search and in the vignette as