I dont think this could be done easily under the current API, as ExpQuad kernel needs raw x instead of distance matrix (ie, Dmat), and the same goes for SparseApprox as it need actually location x to set up the induce point.
I dont think this could be done easily under the current API, as ExpQuad kernel needs raw x instead of distance matrix (ie, Dmat), and the same goes for SparseApprox as it need actually location x to set up the induce point.