I know that the sparse matrix representation is based on the column representation, the data structure stores the nonzero entries in each column.
Thus A(:,2) (taking out the second column) is efficiently implemented.
How about A(:,2), taking the second row?
Thanks very much!
Regards,
-- Yin Zhu, Ph.D. Student Department of Computer Science and Engineering Hong Kong University of Science and Technology
E-Mail: address@hidden or address@hidden