int main(int argc, char **argv)
{
Stokes s;
KSP ksp;
PetscErrorCode ierr;
ierr = PetscInitialize(&argc, &argv, NULL, help);CHKERRQ(ierr);
s.nx = 4;
s.ny = 6;
ierr = PetscOptionsGetInt(NULL, "-nx", &s.nx, NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetInt(NULL, "-ny", &s.ny, NULL);CHKERRQ(ierr);
s.hx = 2.0/s.nx;
s.hy = 1.0/s.ny;
s.userPC = s.userKSP = PETSC_FALSE;
ierr = PetscOptionsHasName(NULL, "-user_pc", &s.userPC);CHKERRQ(ierr);
ierr = PetscOptionsHasName(NULL, "-user_ksp", &s.userKSP);CHKERRQ(ierr);
ierr = StokesSetupMatrix(&s);CHKERRQ(ierr);
ierr = StokesSetupIndexSets(&s);CHKERRQ(ierr);
ierr = StokesSetupVectors(&s);CHKERRQ(ierr);
ierr = KSPCreate(PETSC_COMM_WORLD, &ksp);CHKERRQ(ierr);
ierr = KSPSetOperators(ksp, s.A, s.A);CHKERRQ(ierr);
ierr = KSPSetFromOptions(ksp);CHKERRQ(ierr);
ierr = StokesSetupPC(&s, ksp);CHKERRQ(ierr);
ierr = KSPSolve(ksp, s.b, s.x);CHKERRQ(ierr);
/* don't trust, verify! */
ierr = StokesCalcResidual(&s);CHKERRQ(ierr);
ierr = StokesCalcError(&s);CHKERRQ(ierr);
ierr = StokesWriteSolution(&s);CHKERRQ(ierr);
ierr = KSPDestroy(&ksp);CHKERRQ(ierr);
ierr = MatDestroy(&s.subA[0]);CHKERRQ(ierr);
ierr = MatDestroy(&s.subA[1]);CHKERRQ(ierr);
ierr = MatDestroy(&s.subA[2]);CHKERRQ(ierr);
ierr = MatDestroy(&s.subA[3]);CHKERRQ(ierr);
ierr = MatDestroy(&s.A);CHKERRQ(ierr);
ierr = VecDestroy(&s.x);CHKERRQ(ierr);
ierr = VecDestroy(&s.b);CHKERRQ(ierr);
ierr = VecDestroy(&s.y);CHKERRQ(ierr);
ierr = MatDestroy(&s.myS);CHKERRQ(ierr);
ierr = PetscFinalize();CHKERRQ(ierr);
return 0;
}
Stokes s; KSP ksp; PetscErrorCode ierr; ierr = PetscInitialize(&argc, &argv, NULL, help);CHKERRQ(ierr); s.nx = 4; s.ny = 6; ierr = PetscOptionsGetInt(NULL,NULL, "-nx", &s.nx, NULL);CHKERRQ(ierr); ierr = PetscOptionsGetInt(NULL, NULL,"-ny", &s.ny, NULL);CHKERRQ(ierr); s.hx = 2.0/s.nx; s.hy = 1.0/s.ny; s.userPC = s.userKSP = PETSC_FALSE; ierr = PetscOptionsHasName(NULL,NULL, "-user_pc", &s.userPC);CHKERRQ(ierr); ierr = PetscOptionsHasName(NULL,NULL, "-user_ksp", &s.userKSP);CHKERRQ(ierr); ierr = StokesSetupMatrix(&s);CHKERRQ(ierr); ierr = StokesSetupIndexSets(&s);CHKERRQ(ierr); ierr = StokesSetupVectors(&s);CHKERRQ(ierr); ierr = KSPCreate(PETSC_COMM_WORLD, &ksp);CHKERRQ(ierr); ierr = KSPSetOperators(ksp, s.A, s.A);CHKERRQ(ierr); ierr = KSPSetFromOptions(ksp);CHKERRQ(ierr); ierr = StokesSetupPC(&s, ksp);CHKERRQ(ierr); ierr = KSPSolve(ksp, s.b, s.x);CHKERRQ(ierr); /* don't trust, verify! */ ierr = StokesCalcResidual(&s);CHKERRQ(ierr); ierr = StokesCalcError(&s);CHKERRQ(ierr); ierr = StokesWriteSolution(&s);CHKERRQ(ierr); ierr = KSPDestroy(&ksp);CHKERRQ(ierr);