Formal class 'dgCMatrix' [package "Matrix"] with 6 slots ..@ i : int [1:3000000] 0 1 2 3 4 5 6 7 8 9 ... ..@ p : int [1:4] 0 1000000 2000000 3000000 ..@ Dim : int [1:2] 1000000 3 ..@ Dimnames:List of 2 .. ..$ : NULL .. ..$ : chr [1:3] "CUI1" "...