1c4762a1bSJed Brown 2c4762a1bSJed Brown static char help[] = "Demonstrates the use of fast Richardson for SOR. And\n\ 3c4762a1bSJed Brown also tests the MatSOR() routines. Input parameters are:\n\ 4c4762a1bSJed Brown -n <n> : problem dimension\n\n"; 5c4762a1bSJed Brown 6c4762a1bSJed Brown #include <petscksp.h> 7c4762a1bSJed Brown #include <petscpc.h> 8c4762a1bSJed Brown 9c4762a1bSJed Brown int main(int argc,char **args) 10c4762a1bSJed Brown { 11c4762a1bSJed Brown Mat mat; /* matrix */ 12c4762a1bSJed Brown Vec b,ustar,u; /* vectors (RHS, exact solution, approx solution) */ 13c4762a1bSJed Brown PC pc; /* PC context */ 14c4762a1bSJed Brown KSP ksp; /* KSP context */ 15c4762a1bSJed Brown PetscErrorCode ierr; 16c4762a1bSJed Brown PetscInt n = 10,i,its,col[3]; 17c4762a1bSJed Brown PetscScalar value[3]; 18c4762a1bSJed Brown KSPType kspname; 19c4762a1bSJed Brown PCType pcname; 20c4762a1bSJed Brown 21c4762a1bSJed Brown ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr; 22*5f80ce2aSJacob Faibussowitsch CHKERRQ(PetscOptionsGetInt(NULL,NULL,"-n",&n,NULL)); 23c4762a1bSJed Brown 24c4762a1bSJed Brown /* Create and initialize vectors */ 25*5f80ce2aSJacob Faibussowitsch CHKERRQ(VecCreateSeq(PETSC_COMM_SELF,n,&b)); 26*5f80ce2aSJacob Faibussowitsch CHKERRQ(VecCreateSeq(PETSC_COMM_SELF,n,&ustar)); 27*5f80ce2aSJacob Faibussowitsch CHKERRQ(VecCreateSeq(PETSC_COMM_SELF,n,&u)); 28*5f80ce2aSJacob Faibussowitsch CHKERRQ(VecSet(ustar,1.0)); 29*5f80ce2aSJacob Faibussowitsch CHKERRQ(VecSet(u,0.0)); 30c4762a1bSJed Brown 31c4762a1bSJed Brown /* Create and assemble matrix */ 32*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatCreate(PETSC_COMM_SELF,&mat)); 33*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatSetType(mat,MATSEQAIJ)); 34*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatSetSizes(mat,n,n,n,n)); 35*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatSetFromOptions(mat)); 36*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatSeqAIJSetPreallocation(mat,3,NULL)); 37*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatSeqBAIJSetPreallocation(mat,1,3,NULL)); 38*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatSeqSBAIJSetPreallocation(mat,1,3,NULL)); 39*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatSeqSELLSetPreallocation(mat,3,NULL)); 40c4762a1bSJed Brown value[0] = -1.0; value[1] = 2.0; value[2] = -1.0; 41c4762a1bSJed Brown for (i=1; i<n-1; i++) { 42c4762a1bSJed Brown col[0] = i-1; col[1] = i; col[2] = i+1; 43*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatSetValues(mat,1,&i,3,col,value,INSERT_VALUES)); 44c4762a1bSJed Brown } 45c4762a1bSJed Brown i = n - 1; col[0] = n - 2; col[1] = n - 1; 46*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatSetValues(mat,1,&i,2,col,value,INSERT_VALUES)); 47c4762a1bSJed Brown i = 0; col[0] = 0; col[1] = 1; value[0] = 2.0; value[1] = -1.0; 48*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatSetValues(mat,1,&i,2,col,value,INSERT_VALUES)); 49*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatAssemblyBegin(mat,MAT_FINAL_ASSEMBLY)); 50*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatAssemblyEnd(mat,MAT_FINAL_ASSEMBLY)); 51c4762a1bSJed Brown 52c4762a1bSJed Brown /* Compute right-hand-side vector */ 53*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatMult(mat,ustar,b)); 54c4762a1bSJed Brown 55c4762a1bSJed Brown /* Create PC context and set up data structures */ 56*5f80ce2aSJacob Faibussowitsch CHKERRQ(PCCreate(PETSC_COMM_WORLD,&pc)); 57*5f80ce2aSJacob Faibussowitsch CHKERRQ(PCSetType(pc,PCNONE)); 58*5f80ce2aSJacob Faibussowitsch CHKERRQ(PCSetFromOptions(pc)); 59*5f80ce2aSJacob Faibussowitsch CHKERRQ(PCSetOperators(pc,mat,mat)); 60*5f80ce2aSJacob Faibussowitsch CHKERRQ(PCSetUp(pc)); 61c4762a1bSJed Brown 62c4762a1bSJed Brown /* Create KSP context and set up data structures */ 63*5f80ce2aSJacob Faibussowitsch CHKERRQ(KSPCreate(PETSC_COMM_WORLD,&ksp)); 64*5f80ce2aSJacob Faibussowitsch CHKERRQ(KSPSetType(ksp,KSPRICHARDSON)); 65*5f80ce2aSJacob Faibussowitsch CHKERRQ(KSPSetFromOptions(ksp)); 66*5f80ce2aSJacob Faibussowitsch CHKERRQ(PCSetOperators(pc,mat,mat)); 67*5f80ce2aSJacob Faibussowitsch CHKERRQ(KSPSetPC(ksp,pc)); 68*5f80ce2aSJacob Faibussowitsch CHKERRQ(KSPSetUp(ksp)); 69c4762a1bSJed Brown 70c4762a1bSJed Brown /* Solve the problem */ 71*5f80ce2aSJacob Faibussowitsch CHKERRQ(KSPGetType(ksp,&kspname)); 72*5f80ce2aSJacob Faibussowitsch CHKERRQ(PCGetType(pc,&pcname)); 73*5f80ce2aSJacob Faibussowitsch CHKERRQ(PetscPrintf(PETSC_COMM_SELF,"Running %s with %s preconditioning\n",kspname,pcname)); 74*5f80ce2aSJacob Faibussowitsch CHKERRQ(KSPSolve(ksp,b,u)); 75*5f80ce2aSJacob Faibussowitsch CHKERRQ(KSPGetIterationNumber(ksp,&its)); 76*5f80ce2aSJacob Faibussowitsch CHKERRQ(PetscPrintf(PETSC_COMM_WORLD,"Number of iterations %D\n",its)); 77c4762a1bSJed Brown 78c4762a1bSJed Brown /* Free data structures */ 79*5f80ce2aSJacob Faibussowitsch CHKERRQ(KSPDestroy(&ksp)); 80*5f80ce2aSJacob Faibussowitsch CHKERRQ(VecDestroy(&u)); 81*5f80ce2aSJacob Faibussowitsch CHKERRQ(VecDestroy(&ustar)); 82*5f80ce2aSJacob Faibussowitsch CHKERRQ(VecDestroy(&b)); 83*5f80ce2aSJacob Faibussowitsch CHKERRQ(MatDestroy(&mat)); 84*5f80ce2aSJacob Faibussowitsch CHKERRQ(PCDestroy(&pc)); 85c4762a1bSJed Brown ierr = PetscFinalize(); 86c4762a1bSJed Brown return ierr; 87c4762a1bSJed Brown } 88c4762a1bSJed Brown 89c4762a1bSJed Brown /*TEST 90c4762a1bSJed Brown 91c4762a1bSJed Brown testset: 92c4762a1bSJed Brown args: -ksp_type gmres -ksp_monitor_short -pc_type sor -pc_sor_symmetric 93c4762a1bSJed Brown output_file: output/ex3_1.out 94c4762a1bSJed Brown test: 95c4762a1bSJed Brown suffix: sor_aij 96c4762a1bSJed Brown test: 97c4762a1bSJed Brown suffix: sor_seqbaij 98c4762a1bSJed Brown args: -mat_type seqbaij 99c4762a1bSJed Brown test: 100c4762a1bSJed Brown suffix: sor_seqsbaij 101c4762a1bSJed Brown args: -mat_type seqbaij 102c4762a1bSJed Brown test: 103c4762a1bSJed Brown suffix: sor_seqsell 104c4762a1bSJed Brown args: -mat_type seqsell 105c4762a1bSJed Brown 106c4762a1bSJed Brown TEST*/ 107