I am wondering if you can compute the SVD/eigenvectors of a rank r matrix of size n*n in time O(n^2 r)? My understanding is that standard eigenvector computations involve bringing matrix into Hesseberg form which costs O(n^3) operations.
Thanks.
I am wondering if you can compute the SVD/eigenvectors of a rank r matrix of size n*n in time O(n^2 r)? My understanding is that standard eigenvector computations involve bringing matrix into Hesseberg form which costs O(n^3) operations.
Thanks.
Check out Halko-Martinsson-Tropp