Hi!

I am trying to use Jacobi iteration on magma. And I know the functions(sgemv and sgemm), but it must be A*B + C and A*X + y, which do something unnecessary. Does the lapack or magma fix this problem, or if I put zero in C or y, it will not be computed?

Thanks for answering.

David

## How to do A*B and A*x only

### Re: How to do A*B and A*x only

Is the only way is to set beta 0? By lapack, when setting beta 0, it won't computing the rest.

### Re: How to do A*B and A*x only

Yes, set beta=0. Also, y or C should be initialized to valid numbers, i.e., not NAN or INF, which would be propagated.

-mark

-mark

### Re: How to do A*B and A*x only

I use cudaMemset to make sure there is not garbage in that section of memory