do you have to sort rows of a sparse matrix when doing a PCG solver?

I am working on some software that does a sparse matrix-vector multiply. The matrix is stored i开发者_StackOverflown a coordinate format (a row and column index for each non-zero).

They are performing a sort operation that sorts the column index in order for that row (that is because of some boundary conditions for this FEM problem). Is there some necessity that this needs to happen?

The answer is no. This was done by the previous developer as a way to calculate the total number of rows in the mesh.