Does boost has a library to parse a sparse matrix to get the index the non-zero element value? E.g. given this matrix: 1 2 0 0 0 3 9 0 0 1 4 0 We hope it to return A = [ 1 2 3 9 1 4 ] IA = [ 1 3 5 7 ] JA = [ 1 2 2 3 2 3 ] Let NNZ denote the number of nonzero entries of Matrix. The first array is A, which is of length NNZ, and holds all nonzero entries of M in left-to-right top-to-bottom order. The second array is IA, which is of length m + 1 (i.e., one entry per row, plus one). IA(i) contains the index in A of the first nonzero element of row i. Row i of the original matrix extends from A(IA(i)) to A(IA(i+1)-1). The third array, JA, contains the column index of each element of A, so it also is of length NNZ. Is there any implementation for handling such a large matrix to give us A, IA and JA, without having have to slurp all the files into RAM? Because the actual dimension is very large 10^6 to 10^7. Regards, G.V.