The compressed sparse row (CSR) represents a matrix by three (one-dimensional) arrays, that respectively contain nonzero values, the extents of rows, and column indices.
1 2 3 0
0 4 5 0
6 0 7 8
0 0 0 9
0 4 5 0
6 0 7 8
0 0 0 9
0 3 5 8 9
0 1 2 1 2 0 2 3 3
1 2 3 4 5 6 7 8 9
Offset
Indices
Weights
row+1
Matrix