Dear managers and users, I got a problem when using PETSc to make parallel codes. Could you please help me out?
Basically, I need to do is to update the values of some blocks of a large matrix (not the whole matrix), and I need to do it many times in a big loop. These blocks could be assembled to the same or different processors. If using "MatSetValues", it would spend much time for the data transfer between different processors. I expect "MatSubMatrixUpdate" could do the job better. Am I correct? But I can not find an example of using "MatSubMatrixUpdate" on the website. It is said that the "MatSubMatrixUpdate" is only in a "developer" level and the users should use some other functions to replace it. What other functions should I use? Thank you for your attention! -- Shaohao Chen Department of Physics & Astronomy, Louisiana State University, Baton Rouge, LA
