<html><body><div style="font-family: times new roman, new york, times, serif; font-size: 12pt; color: #000000"><div>Hello everyone,<br></div><div><br></div><div>I'm trying to solve a system iteratively through conjugate gradient with jacobi preconditionning.<br></div><div>Thing is the system matrix is a matshell. </div><div>When I run the code matgetdiagonal returns an error : "MatGetDiagonal() line ......... /petsc/3.4.3/src/mat/interface/matrix.c Mat type shell"</div><div>Is matgetiagonal function enable to act on a matshell?<br></div><div><br></div><div>if someone has a clue on it....<br></div><div><br></div><div>thanks a lot<br></div><div>regards<br></div><div>Nicolas<br></div></div></body></html>