Optimize indexing when fitting models; optimize nonzero call
Optimize indexing when fitting models; optimize nonzero call

c11/yatsm,jmorton/yatsm,jmorton/yatsm,c11/yatsm,valpasq/yatsm,valpasq/yatsm,jmorton/yatsm,ceholden/yatsm,ceholden/yatsm