339     Mat B2, T3, T4;  in main()  local
342     PetscCall(MatDuplicate(B, MAT_DO_NOT_COPY_VALUES, &T4));  in main()
343     PetscCall(MatSetRandom(T4, NULL));  in main()
344     PetscCall(MatAXPY(B2, 1.0, T4, SAME_NONZERO_PATTERN));  in main()
346 …PetscCall(MatDenseGetSubMatrix(T4, PETSC_DECIDE, PETSC_DECIDE, PetscMin(1, K - 1), PetscMin(2, K),…  in main()
356     PetscCall(MatDenseRestoreSubMatrix(T4, &T2));  in main()
360     PetscCall(MatDestroy(&T4));  in main()
363       PetscCall(MatDuplicate(B, MAT_DO_NOT_COPY_VALUES, &T4));  in main()
364       PetscCall(MatSetRandom(T4, NULL));  in main()
365       PetscCall(MatAXPY(B2, 1.0, T4, SAME_NONZERO_PATTERN));  in main()
367 … PetscCall(MatDenseGetSubMatrix(T4, N - 2, PETSC_DECIDE, PetscMin(1, K - 1), PetscMin(2, K), &T2));  in main()
377       PetscCall(MatDenseRestoreSubMatrix(T4, &T2));  in main()
381       PetscCall(MatDestroy(&T4));  in main()
383       PetscCall(MatDuplicate(B, MAT_DO_NOT_COPY_VALUES, &T4));  in main()
384       PetscCall(MatSetRandom(T4, NULL));  in main()
385       PetscCall(MatAXPY(B2, 1.0, T4, SAME_NONZERO_PATTERN));  in main()
387       PetscCall(MatDenseGetSubMatrix(T4, PETSC_DECIDE, 2, PetscMin(1, K - 1), PetscMin(2, K), &T2));  in main()
397       PetscCall(MatDenseRestoreSubMatrix(T4, &T2));  in main()
401       PetscCall(MatDestroy(&T4));  in main()