int main(int argc,char **args)
{
Mat C,A;
PetscInt i,j;
PetscErrorCode ierr;
PetscScalar v;
PC pc;
Vec xtmp;
ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
ierr = MatCreate(PETSC_COMM_WORLD,&C);CHKERRQ(ierr);
ierr = MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,3,3);CHKERRQ(ierr);
ierr = MatSetFromOptions(C);CHKERRQ(ierr);
ierr = MatSetUp(C);CHKERRQ(ierr);
ierr = VecCreateSeq(PETSC_COMM_WORLD,3,&xtmp);CHKERRQ(ierr);
i = 0; j = 0; v = 4;
ierr = MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
i = 0; j = 2; v = 1;
ierr = MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
i = 1; j = 0; v = 1;
ierr = MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
i = 1; j = 1; v = 4;
ierr = MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
i = 2; j = 1; v = 1;
ierr = MatSetValues(C,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatView(C,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
ierr = PCCreate(PETSC_COMM_WORLD,&pc);CHKERRQ(ierr);
ierr = PCSetFromOptions(pc);CHKERRQ(ierr);
ierr = PCSetOperators(pc,C,C);CHKERRQ(ierr);
ierr = PCSetUp(pc);CHKERRQ(ierr);
ierr = PCFactorGetMatrix(pc,&A);CHKERRQ(ierr);
ierr = MatView(A,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
ierr = PCDestroy(&pc);CHKERRQ(ierr);
ierr = VecDestroy(&xtmp);CHKERRQ(ierr);
ierr = MatDestroy(&C);CHKERRQ(ierr);
ierr = PetscFinalize();
return ierr;
}
int main(int argc,char **argv)
{
KSP ksp;
PC pc;
Mat A,M;
Vec X,B,D;
MPI_Comm comm;
PetscScalar v;
KSPConvergedReason reason;
PetscInt i,j,its;
PetscErrorCode ierr;
PetscFunctionBegin;
ierr = PetscInitialize(&argc,&argv,0,help);CHKERRQ(ierr);
ierr = PetscOptionsSetValue("-options_left",PETSC_NULL);CHKERRQ(ierr);
comm = MPI_COMM_SELF;
/*
* Construct the Kershaw matrix
* and a suitable rhs / initial guess
*/
ierr = MatCreateSeqAIJ(comm,4,4,4,0,&A);CHKERRQ(ierr);
ierr = VecCreateSeq(comm,4,&B);CHKERRQ(ierr);
ierr = VecDuplicate(B,&X);CHKERRQ(ierr);
for (i=0; i<4; i++) {
v=3;
ierr = MatSetValues(A,1,&i,1,&i,&v,INSERT_VALUES);CHKERRQ(ierr);
v=1;
ierr = VecSetValues(B,1,&i,&v,INSERT_VALUES);CHKERRQ(ierr);
ierr = VecSetValues(X,1,&i,&v,INSERT_VALUES);CHKERRQ(ierr);
}
i=0; v=0;
ierr = VecSetValues(X,1,&i,&v,INSERT_VALUES);CHKERRQ(ierr);
for (i=0; i<3; i++) {
v=-2; j=i+1;
ierr = MatSetValues(A,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
ierr = MatSetValues(A,1,&j,1,&i,&v,INSERT_VALUES);CHKERRQ(ierr);
}
i=0; j=3; v=2;
ierr = MatSetValues(A,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
ierr = MatSetValues(A,1,&j,1,&i,&v,INSERT_VALUES);CHKERRQ(ierr);
ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = VecAssemblyBegin(B);CHKERRQ(ierr);
ierr = VecAssemblyEnd(B);CHKERRQ(ierr);
printf("\nThe Kershaw matrix:\n\n"); MatView(A,0);
/*
* A Conjugate Gradient method
* with ILU(0) preconditioning
*/
ierr = KSPCreate(comm,&ksp);CHKERRQ(ierr);
ierr = KSPSetOperators(ksp,A,A,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);
ierr = KSPSetType(ksp,KSPCG);CHKERRQ(ierr);
ierr = KSPSetInitialGuessNonzero(ksp,PETSC_TRUE);CHKERRQ(ierr);
/*
* ILU preconditioner;
* The iterative method will break down unless you comment in the SetShift
* line below, or use the -pc_factor_shift_positive_definite option.
* Run the code twice: once as given to see the negative pivot and the
* divergence behaviour, then comment in the Shift line, or add the
* command line option, and see that the pivots are all positive and
* the method converges.
*/
ierr = KSPGetPC(ksp,&pc);CHKERRQ(ierr);
ierr = PCSetType(pc,PCICC);CHKERRQ(ierr);
/* ierr = PCFactorSetShiftType(prec,MAT_SHIFT_POSITIVE_DEFINITE);CHKERRQ(ierr); */
ierr = KSPSetFromOptions(ksp);CHKERRQ(ierr);
ierr = KSPSetUp(ksp);CHKERRQ(ierr);
/*
* Now that the factorisation is done, show the pivots;
* note that the last one is negative. This in itself is not an error,
* but it will make the iterative method diverge.
*/
ierr = PCFactorGetMatrix(pc,&M);CHKERRQ(ierr);
ierr = VecDuplicate(B,&D);CHKERRQ(ierr);
ierr = MatGetDiagonal(M,D);CHKERRQ(ierr);
printf("\nPivots:\n\n"); VecView(D,0);
/*
* Solve the system;
* without the shift this will diverge with
* an indefinite preconditioner
*/
ierr = KSPSolve(ksp,B,X);CHKERRQ(ierr);
ierr = KSPGetConvergedReason(ksp,&reason);CHKERRQ(ierr);
if (reason==KSP_DIVERGED_INDEFINITE_PC) {
printf("\nDivergence because of indefinite preconditioner;\n");
printf("Run the executable again but with -pc_factor_shift_positive_definite option.\n");
} else if (reason<0) {
printf("\nOther kind of divergence: this should not happen.\n");
} else {
ierr = KSPGetIterationNumber(ksp,&its);CHKERRQ(ierr);
printf("\nConvergence in %d iterations.\n",(int)its);
}
printf("\n");
ierr = KSPDestroy(&ksp);CHKERRQ(ierr);
ierr = MatDestroy(&A);CHKERRQ(ierr);
ierr = VecDestroy(&B);CHKERRQ(ierr);
ierr = VecDestroy(&X);CHKERRQ(ierr);
ierr = VecDestroy(&D);CHKERRQ(ierr);
PetscFinalize();
PetscFunctionReturn(0);
}
PetscInt main(PetscInt argc,char **args)
{
Mat A,As;
PetscBool flg,disp_mat=PETSC_FALSE;
PetscErrorCode ierr;
PetscMPIInt size,rank;
PetscInt i,j;
PetscScalar v,sigma2;
PetscRandom rctx;
PetscReal h2,sigma1=100.0;
PetscInt dim,Ii,J,n = 3,use_random,rstart,rend;
KSP ksp;
PC pc;
Mat F;
PetscInt nneg, nzero, npos;
PetscInitialize(&argc,&args,(char *)0,help);
#if !defined(PETSC_USE_COMPLEX)
SETERRQ(PETSC_COMM_WORLD,1,"This example requires complex numbers");
#endif
ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr);
ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
ierr = PetscOptionsHasName(PETSC_NULL, "-display_mat", &disp_mat);CHKERRQ(ierr);
ierr = PetscOptionsGetReal(PETSC_NULL,"-sigma1",&sigma1,PETSC_NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetInt(PETSC_NULL,"-n",&n,PETSC_NULL);CHKERRQ(ierr);
dim = n*n;
ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr);
ierr = MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,dim,dim);CHKERRQ(ierr);
ierr = MatSetType(A,MATAIJ);CHKERRQ(ierr);
ierr = MatSetFromOptions(A);CHKERRQ(ierr);
ierr = PetscOptionsHasName(PETSC_NULL,"-norandom",&flg);CHKERRQ(ierr);
if (flg) use_random = 0;
else use_random = 1;
if (use_random) {
ierr = PetscRandomCreate(PETSC_COMM_WORLD,&rctx);CHKERRQ(ierr);
ierr = PetscRandomSetFromOptions(rctx);CHKERRQ(ierr);
ierr = PetscRandomSetInterval(rctx,0.0,PETSC_i);CHKERRQ(ierr);
ierr = PetscRandomGetValue(rctx,&sigma2);CHKERRQ(ierr); /* RealPart(sigma2) == 0.0 */
} else {
sigma2 = 10.0*PETSC_i;
}
h2 = 1.0/((n+1)*(n+1));
ierr = MatGetOwnershipRange(A,&rstart,&rend);CHKERRQ(ierr);
for (Ii=rstart; Ii<rend; Ii++) {
v = -1.0; i = Ii/n; j = Ii - i*n;
if (i>0) {
J = Ii-n; ierr = MatSetValues(A,1,&Ii,1,&J,&v,ADD_VALUES);CHKERRQ(ierr);}
if (i<n-1) {
J = Ii+n; ierr = MatSetValues(A,1,&Ii,1,&J,&v,ADD_VALUES);CHKERRQ(ierr);}
if (j>0) {
J = Ii-1; ierr = MatSetValues(A,1,&Ii,1,&J,&v,ADD_VALUES);CHKERRQ(ierr);}
if (j<n-1) {
J = Ii+1; ierr = MatSetValues(A,1,&Ii,1,&J,&v,ADD_VALUES);CHKERRQ(ierr);}
v = 4.0 - sigma1*h2;
ierr = MatSetValues(A,1,&Ii,1,&Ii,&v,ADD_VALUES);CHKERRQ(ierr);
}
ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
/* Check whether A is symmetric */
ierr = PetscOptionsHasName(PETSC_NULL, "-check_symmetric", &flg);CHKERRQ(ierr);
if (flg) {
Mat Trans;
ierr = MatTranspose(A,MAT_INITIAL_MATRIX, &Trans);
ierr = MatEqual(A, Trans, &flg);
if (!flg) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_USER,"A is not symmetric");
ierr = MatDestroy(&Trans);CHKERRQ(ierr);
}
ierr = MatSetOption(A,MAT_SYMMETRIC,PETSC_TRUE);CHKERRQ(ierr);
/* make A complex Hermitian */
Ii = 0; J = dim-1;
if (Ii >= rstart && Ii < rend){
v = sigma2*h2; /* RealPart(v) = 0.0 */
ierr = MatSetValues(A,1,&Ii,1,&J,&v,ADD_VALUES);CHKERRQ(ierr);
v = -sigma2*h2;
ierr = MatSetValues(A,1,&J,1,&Ii,&v,ADD_VALUES);CHKERRQ(ierr);
}
Ii = dim-2; J = dim-1;
if (Ii >= rstart && Ii < rend){
v = sigma2*h2; /* RealPart(v) = 0.0 */
ierr = MatSetValues(A,1,&Ii,1,&J,&v,ADD_VALUES);CHKERRQ(ierr);
v = -sigma2*h2;
ierr = MatSetValues(A,1,&J,1,&Ii,&v,ADD_VALUES);CHKERRQ(ierr);
}
ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
/* Check whether A is Hermitian */
ierr = PetscOptionsHasName(PETSC_NULL, "-check_Hermitian", &flg);CHKERRQ(ierr);
if (flg) {
Mat Hermit;
if (disp_mat){
if (!rank) printf(" A:\n");
ierr = MatView(A,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
}
ierr = MatHermitianTranspose(A,MAT_INITIAL_MATRIX, &Hermit);
if (disp_mat){
if (!rank) printf(" A_Hermitian:\n");
ierr = MatView(Hermit,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
}
ierr = MatEqual(A, Hermit, &flg);
if (!flg) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_USER,"A is not Hermitian");
ierr = MatDestroy(&Hermit);CHKERRQ(ierr);
}
ierr = MatSetOption(A,MAT_HERMITIAN,PETSC_TRUE);CHKERRQ(ierr);
/* Create a Hermitian matrix As in sbaij format */
ierr = MatConvert(A,MATSBAIJ,MAT_INITIAL_MATRIX,&As);CHKERRQ(ierr);
if (disp_mat){
if (!rank) {ierr = PetscPrintf(PETSC_COMM_SELF," As:\n");CHKERRQ(ierr);}
ierr = MatView(As,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
}
/* Test MatGetInertia() */
ierr = KSPCreate(PETSC_COMM_WORLD,&ksp);CHKERRQ(ierr);
ierr = KSPSetType(ksp,KSPPREONLY);CHKERRQ(ierr);
ierr = KSPSetOperators(ksp,As,As,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);
ierr = KSPGetPC(ksp,&pc);CHKERRQ(ierr);
ierr = PCSetType(pc,PCCHOLESKY);CHKERRQ(ierr);
ierr = PCSetFromOptions(pc);CHKERRQ(ierr);
ierr = PCSetUp(pc);CHKERRQ(ierr);
ierr = PCFactorGetMatrix(pc,&F);CHKERRQ(ierr);
ierr = MatGetInertia(F,&nneg,&nzero,&npos);CHKERRQ(ierr);
ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
if (!rank){
ierr = PetscPrintf(PETSC_COMM_SELF," MatInertia: nneg: %D, nzero: %D, npos: %D\n",nneg,nzero,npos);CHKERRQ(ierr);
}
/* Free spaces */
ierr = KSPDestroy(&ksp);CHKERRQ(ierr);
if (use_random) {ierr = PetscRandomDestroy(&rctx);CHKERRQ(ierr);}
ierr = MatDestroy(&A);CHKERRQ(ierr);
ierr = MatDestroy(&As);CHKERRQ(ierr);
ierr = PetscFinalize();
return 0;
}
int main(int argc,char **args)
{
Mat A,B,F;
PetscErrorCode ierr;
KSP ksp;
PC pc;
PetscInt N, n=10, m, Istart, Iend, II, J, i,j;
PetscInt nneg, nzero, npos;
PetscScalar v,sigma;
PetscBool flag,loadA=PETSC_FALSE,loadB=PETSC_FALSE;
char file[2][PETSC_MAX_PATH_LEN];
PetscViewer viewer;
PetscMPIInt rank;
PetscInitialize(&argc,&args,(char *)0,help);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Compute the matrices that define the eigensystem, Ax=kBx
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = PetscOptionsGetString(PETSC_NULL,"-fA",file[0],PETSC_MAX_PATH_LEN,&loadA);CHKERRQ(ierr);
if (loadA) {
ierr = PetscViewerBinaryOpen(PETSC_COMM_WORLD,file[0],FILE_MODE_READ,&viewer);CHKERRQ(ierr);
ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr);
ierr = MatSetType(A,MATSBAIJ);CHKERRQ(ierr);
ierr = MatLoad(A,viewer);CHKERRQ(ierr);
ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
ierr = PetscOptionsGetString(PETSC_NULL,"-fB",file[1],PETSC_MAX_PATH_LEN,&loadB);CHKERRQ(ierr);
if (loadB){
/* load B to get A = A + sigma*B */
ierr = PetscViewerBinaryOpen(PETSC_COMM_WORLD,file[1],FILE_MODE_READ,&viewer);CHKERRQ(ierr);
ierr = MatCreate(PETSC_COMM_WORLD,&B);CHKERRQ(ierr);
ierr = MatSetType(B,MATSBAIJ);CHKERRQ(ierr);
ierr = MatLoad(B,viewer);CHKERRQ(ierr);
ierr = PetscViewerDestroy(&viewer);CHKERRQ(ierr);
}
}
if (!loadA) { /* Matrix A is copied from slepc-3.0.0-p6/src/examples/ex13.c. */
ierr = PetscOptionsGetInt(PETSC_NULL,"-n",&n,PETSC_NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetInt(PETSC_NULL,"-m",&m,&flag);CHKERRQ(ierr);
if( flag==PETSC_FALSE ) m=n;
N = n*m;
ierr = MatCreate(PETSC_COMM_WORLD,&A);CHKERRQ(ierr);
ierr = MatSetSizes(A,PETSC_DECIDE,PETSC_DECIDE,N,N);CHKERRQ(ierr);
ierr = MatSetType(A,MATSBAIJ);CHKERRQ(ierr);
ierr = MatSetFromOptions(A);CHKERRQ(ierr);
ierr = MatSetUp(A);CHKERRQ(ierr);
ierr = MatSetOption(A,MAT_IGNORE_LOWER_TRIANGULAR,PETSC_TRUE);CHKERRQ(ierr);
ierr = MatGetOwnershipRange(A,&Istart,&Iend);CHKERRQ(ierr);
for( II=Istart; II<Iend; II++ ) {
v = -1.0; i = II/n; j = II-i*n;
if(i>0) { J=II-n; MatSetValues(A,1,&II,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr); }
if(i<m-1) { J=II+n; MatSetValues(A,1,&II,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr); }
if(j>0) { J=II-1; MatSetValues(A,1,&II,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr); }
if(j<n-1) { J=II+1; MatSetValues(A,1,&II,1,&J,&v,INSERT_VALUES);CHKERRQ(ierr); }
v=4.0; MatSetValues(A,1,&II,1,&II,&v,INSERT_VALUES);CHKERRQ(ierr);
}
ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
}
/* ierr = MatView(A,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); */
if (!loadB) {
ierr = MatGetLocalSize(A,&m,&n);CHKERRQ(ierr);
ierr = MatCreate(PETSC_COMM_WORLD,&B);CHKERRQ(ierr);
ierr = MatSetSizes(B,m,n,PETSC_DECIDE,PETSC_DECIDE);CHKERRQ(ierr);
ierr = MatSetType(B,MATSBAIJ);CHKERRQ(ierr);
ierr = MatSetFromOptions(B);CHKERRQ(ierr);
ierr = MatSetUp(B);CHKERRQ(ierr);
ierr = MatSetOption(B,MAT_IGNORE_LOWER_TRIANGULAR,PETSC_TRUE);CHKERRQ(ierr);
ierr = MatGetOwnershipRange(A,&Istart,&Iend);CHKERRQ(ierr);
for( II=Istart; II<Iend; II++ ) {
/* v=4.0; MatSetValues(B,1,&II,1,&II,&v,INSERT_VALUES);CHKERRQ(ierr); */
v=1.0; MatSetValues(B,1,&II,1,&II,&v,INSERT_VALUES);CHKERRQ(ierr);
}
ierr = MatAssemblyBegin(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(B,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
}
/* ierr = MatView(B,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); */
/* Set a shift: A = A - sigma*B */
ierr = PetscOptionsGetScalar(PETSC_NULL,"-sigma",&sigma,&flag);CHKERRQ(ierr);
if (flag){
sigma = -1.0 * sigma;
ierr = MatAXPY(A,sigma,B,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr); /* A <- A - sigma*B */
/* ierr = MatView(A,PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr); */
}
/* Test MatGetInertia() */
ierr = KSPCreate(PETSC_COMM_WORLD,&ksp);CHKERRQ(ierr);
ierr = KSPSetType(ksp,KSPPREONLY);CHKERRQ(ierr);
ierr = KSPSetOperators(ksp,A,A,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);
ierr = KSPGetPC(ksp,&pc);CHKERRQ(ierr);
ierr = PCSetType(pc,PCCHOLESKY);CHKERRQ(ierr);
ierr = PCSetFromOptions(pc);CHKERRQ(ierr);
ierr = PCSetUp(pc);CHKERRQ(ierr);
ierr = PCFactorGetMatrix(pc,&F);CHKERRQ(ierr);
ierr = MatGetInertia(F,&nneg,&nzero,&npos);CHKERRQ(ierr);
ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
if (!rank){
ierr = PetscPrintf(PETSC_COMM_SELF," MatInertia: nneg: %D, nzero: %D, npos: %D\n",nneg,nzero,npos);CHKERRQ(ierr);
}
/* Destroy */
ierr = KSPDestroy(&ksp);CHKERRQ(ierr);
ierr = MatDestroy(&A);CHKERRQ(ierr);
ierr = MatDestroy(&B);CHKERRQ(ierr);
ierr = PetscFinalize();
return 0;
}
// =====================================================
void PetscPreconditioner::set_petsc_preconditioner_type
(const PreconditionerType & preconditioner_type, PC & pc, const int ¶llelOverlapping) {
int ierr = 0;
switch(preconditioner_type) {
case IDENTITY_PRECOND:
ierr = PCSetType(pc, (char*) PCNONE);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case CHOLESKY_PRECOND:
ierr = PCSetType(pc, (char*) PCCHOLESKY);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case ICC_PRECOND:
ierr = PCSetType(pc, (char*) PCICC);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case ILU_PRECOND:
{
int nprocs;
MPI_Comm_size(MPI_COMM_WORLD, &nprocs); //TODO
// In serial, just set the ILU preconditioner type
if(nprocs == 1)
{
ierr = PCSetType(pc, (char*) PCILU);
CHKERRABORT(MPI_COMM_WORLD, ierr);
}
else
{
// But PETSc has no truly parallel ILU, instead you have to set
// an actual parallel preconditioner (e.g. block Jacobi (parlleloverlapping 0) or ASM (parlleloverlapping >0))
// and then assign ILU sub-preconditioners.
set_petsc_preconditioner_type(ASM_PRECOND, pc);
PCASMSetOverlap(pc, parallelOverlapping);
PCSetUp(pc);
// Set ILU as the sub preconditioner type
set_petsc_subpreconditioner_type(PCILU, pc);
}
break;
}
case LU_PRECOND: {
int nprocs;
MPI_Comm_size(MPI_COMM_WORLD, &nprocs);
if(nprocs == 1) {
ierr = PCSetType(pc, (char*) PCLU);
CHKERRABORT(MPI_COMM_WORLD, ierr);
}
else {
ierr = PCSetType(pc, (char*) PCLU);
CHKERRABORT(MPI_COMM_WORLD, ierr);
ierr = PCFactorSetMatSolverPackage(pc, MATSOLVERMUMPS);
CHKERRABORT(MPI_COMM_WORLD, ierr);
ierr = PCFactorSetUpMatSolverPackage(pc);
CHKERRABORT(MPI_COMM_WORLD, ierr);
Mat F;
ierr = PCFactorGetMatrix(pc, &F);
CHKERRABORT(MPI_COMM_WORLD, ierr);
ierr = MatMumpsSetIcntl(F, 14, 30);
CHKERRABORT(MPI_COMM_WORLD, ierr);
}
break;
}
case SLU_PRECOND:
ierr = PCSetType(pc, (char*) PCLU);
CHKERRABORT(MPI_COMM_WORLD, ierr);
ierr = PCFactorSetMatSolverPackage(pc, MATSOLVERSUPERLU_DIST);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break; //here we set the SuperLU_dist solver package
case MLU_PRECOND: //here we set the MUMPS parallel direct solver package
ierr = PCSetType(pc, (char*) PCLU);
CHKERRABORT(MPI_COMM_WORLD, ierr);
ierr = PCFactorSetMatSolverPackage(pc, MATSOLVERMUMPS);
CHKERRABORT(MPI_COMM_WORLD, ierr);
ierr = PCFactorSetUpMatSolverPackage(pc);
CHKERRABORT(MPI_COMM_WORLD, ierr);
Mat F;
ierr = PCFactorGetMatrix(pc, &F);
CHKERRABORT(MPI_COMM_WORLD, ierr);
ierr = MatMumpsSetIcntl(F, 14, 30);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case ULU_PRECOND: //here we set the Umfpack serial direct solver package
ierr = PCSetType(pc, (char*) PCLU);
CHKERRABORT(MPI_COMM_WORLD, ierr);
ierr = PCFactorSetMatSolverPackage(pc, MATSOLVERUMFPACK);
CHKERRABORT(MPI_COMM_WORLD, ierr);
ierr = PCFactorSetUpMatSolverPackage(pc);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case MCC_PRECOND:
ierr = PCSetType(pc, (char*) PCCHOLESKY);
CHKERRABORT(MPI_COMM_WORLD, ierr);
ierr = PCFactorSetMatSolverPackage(pc, MATSOLVERMUMPS);
CHKERRABORT(MPI_COMM_WORLD, ierr); //here we set the MUMPS parallel direct solver package
break;
case ASM_PRECOND:
ierr = PCSetType(pc, (char*) PCASM);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case FIELDSPLIT_PRECOND:
ierr = PCSetType(pc, (char*) PCFIELDSPLIT);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case JACOBI_PRECOND:
ierr = PCSetType(pc, (char*) PCJACOBI);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case BLOCK_JACOBI_PRECOND:
ierr = PCSetType(pc, (char*) PCBJACOBI);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case SOR_PRECOND:
ierr = PCSetType(pc, (char*) PCSOR);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case EISENSTAT_PRECOND:
ierr = PCSetType(pc, (char*) PCEISENSTAT);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case AMG_PRECOND:
ierr = PCSetType(pc, (char*) PCHYPRE);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case MG_PRECOND:
ierr = PCSetType(pc, (char*) PCMG);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
case LSC_PRECOND:
ierr = PCSetType(pc, (char*) PCLSC);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
#if !(PETSC_VERSION_LESS_THAN(2,1,2))
// Only available for PETSC >= 2.1.2
case USER_PRECOND:
ierr = PCSetType(pc, (char*) PCMAT);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
#endif
case SHELL_PRECOND:
ierr = PCSetType(pc, (char*) PCSHELL);
CHKERRABORT(MPI_COMM_WORLD, ierr);
break;
default:
std::cerr << "ERROR: Unsupported PETSC Preconditioner: "
<< preconditioner_type << std::endl
<< "Continuing with PETSC defaults" << std::endl;
}
//Let the commandline override stuff
if(preconditioner_type != AMG_PRECOND && preconditioner_type != MG_PRECOND) PCSetFromOptions(pc); //!!!!!!
}
int main(int argc,char **argv)
{
KSP solver;
PC prec;
Mat A,M;
Vec X,B,D;
MPI_Comm comm;
PetscScalar v;
KSPConvergedReason reason;
PetscInt i,j,its;
PetscErrorCode ierr;
ierr = PetscInitialize(&argc,&argv,0,help);CHKERRQ(ierr);
comm = MPI_COMM_SELF;
/*
* Construct the Kershaw matrix
* and a suitable rhs / initial guess
*/
ierr = MatCreateSeqAIJ(comm,4,4,4,0,&A);CHKERRQ(ierr);
ierr = VecCreateSeq(comm,4,&B);CHKERRQ(ierr);
ierr = VecDuplicate(B,&X);CHKERRQ(ierr);
for (i=0; i<4; i++) {
v = 3;
ierr = MatSetValues(A,1,&i,1,&i,&v,INSERT_VALUES);CHKERRQ(ierr);
v = 1;
ierr = VecSetValues(B,1,&i,&v,INSERT_VALUES);CHKERRQ(ierr);
ierr = VecSetValues(X,1,&i,&v,INSERT_VALUES);CHKERRQ(ierr);
}
i=0; v=0;
ierr = VecSetValues(X,1,&i,&v,INSERT_VALUES);CHKERRQ(ierr);
for (i=0; i<3; i++) {
v = -2; j=i+1;
ierr = MatSetValues(A,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
ierr = MatSetValues(A,1,&j,1,&i,&v,INSERT_VALUES);CHKERRQ(ierr);
}
i=0; j=3; v=2;
ierr = MatSetValues(A,1,&i,1,&j,&v,INSERT_VALUES);CHKERRQ(ierr);
ierr = MatSetValues(A,1,&j,1,&i,&v,INSERT_VALUES);CHKERRQ(ierr);
ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = VecAssemblyBegin(B);CHKERRQ(ierr);
ierr = VecAssemblyEnd(B);CHKERRQ(ierr);
/*
* A Conjugate Gradient method
* with ILU(0) preconditioning
*/
ierr = KSPCreate(comm,&solver);CHKERRQ(ierr);
ierr = KSPSetOperators(solver,A,A);CHKERRQ(ierr);
ierr = KSPSetType(solver,KSPCG);CHKERRQ(ierr);
ierr = KSPSetInitialGuessNonzero(solver,PETSC_TRUE);CHKERRQ(ierr);
/*
* ILU preconditioner;
* this will break down unless you add the Shift line,
* or use the -pc_factor_shift_positive_definite option */
ierr = KSPGetPC(solver,&prec);CHKERRQ(ierr);
ierr = PCSetType(prec,PCILU);CHKERRQ(ierr);
/* ierr = PCFactorSetShiftType(prec,MAT_SHIFT_POSITIVE_DEFINITE);CHKERRQ(ierr); */
ierr = KSPSetFromOptions(solver);CHKERRQ(ierr);
ierr = KSPSetUp(solver);CHKERRQ(ierr);
/*
* Now that the factorisation is done, show the pivots;
* note that the last one is negative. This in itself is not an error,
* but it will make the iterative method diverge.
*/
ierr = PCFactorGetMatrix(prec,&M);CHKERRQ(ierr);
ierr = VecDuplicate(B,&D);CHKERRQ(ierr);
ierr = MatGetDiagonal(M,D);CHKERRQ(ierr);
/*
* Solve the system;
* without the shift this will diverge with
* an indefinite preconditioner
*/
ierr = KSPSolve(solver,B,X);CHKERRQ(ierr);
ierr = KSPGetConvergedReason(solver,&reason);CHKERRQ(ierr);
if (reason==KSP_DIVERGED_INDEFINITE_PC) {
ierr = PetscPrintf(PETSC_COMM_WORLD,"\nDivergence because of indefinite preconditioner;\n");CHKERRQ(ierr);
ierr = PetscPrintf(PETSC_COMM_WORLD,"Run the executable again but with '-pc_factor_shift_type POSITIVE_DEFINITE' option.\n");CHKERRQ(ierr);
} else if (reason<0) {
ierr = PetscPrintf(PETSC_COMM_WORLD,"\nOther kind of divergence: this should not happen.\n");CHKERRQ(ierr);
} else {
ierr = KSPGetIterationNumber(solver,&its);CHKERRQ(ierr);
}
ierr = VecDestroy(&X);CHKERRQ(ierr);
ierr = VecDestroy(&B);CHKERRQ(ierr);
ierr = VecDestroy(&D);CHKERRQ(ierr);
ierr = MatDestroy(&A);CHKERRQ(ierr);
ierr = KSPDestroy(&solver);CHKERRQ(ierr);
PetscFinalize();
return 0;
}
/*@
MatSchurComplementComputeExplicitOperator - Compute the Schur complement matrix explicitly
Collective on Mat
Input Parameter:
. M - the matrix obtained with MatCreateSchurComplement()
Output Parameter:
. S - the Schur complement matrix
Note: This can be expensive, so it is mainly for testing
Level: advanced
.seealso: MatCreateSchurComplement(), MatSchurComplementUpdate()
@*/
PetscErrorCode MatSchurComplementComputeExplicitOperator(Mat M, Mat *S)
{
Mat B, C, D;
KSP ksp;
PC pc;
PetscBool isLU, isILU;
PetscReal fill = 2.0;
PetscErrorCode ierr;
PetscFunctionBegin;
ierr = MatSchurComplementGetSubMatrices(M, NULL, NULL, &B, &C, &D);CHKERRQ(ierr);
ierr = MatSchurComplementGetKSP(M, &ksp);CHKERRQ(ierr);
ierr = KSPGetPC(ksp, &pc);CHKERRQ(ierr);
ierr = PetscObjectTypeCompare((PetscObject) pc, PCLU, &isLU);CHKERRQ(ierr);
ierr = PetscObjectTypeCompare((PetscObject) pc, PCILU, &isILU);CHKERRQ(ierr);
if (isLU || isILU) {
Mat fact, Bd, AinvB, AinvBd;
PetscReal eps = 1.0e-10;
/* This can be sped up for banded LU */
ierr = KSPSetUp(ksp);CHKERRQ(ierr);
ierr = PCFactorGetMatrix(pc, &fact);CHKERRQ(ierr);
ierr = MatConvert(B, MATDENSE, MAT_INITIAL_MATRIX, &Bd);CHKERRQ(ierr);
ierr = MatDuplicate(Bd, MAT_DO_NOT_COPY_VALUES, &AinvBd);CHKERRQ(ierr);
ierr = MatMatSolve(fact, Bd, AinvBd);CHKERRQ(ierr);
ierr = MatDestroy(&Bd);CHKERRQ(ierr);
ierr = MatChop(AinvBd, eps);CHKERRQ(ierr);
ierr = MatConvert(AinvBd, MATAIJ, MAT_INITIAL_MATRIX, &AinvB);CHKERRQ(ierr);
ierr = MatDestroy(&AinvBd);CHKERRQ(ierr);
ierr = MatMatMult(C, AinvB, MAT_INITIAL_MATRIX, fill, S);CHKERRQ(ierr);
ierr = MatDestroy(&AinvB);CHKERRQ(ierr);
} else {
Mat Ainvd, Ainv;
ierr = PCComputeExplicitOperator(pc, &Ainvd);CHKERRQ(ierr);
ierr = MatConvert(Ainvd, MATAIJ, MAT_INITIAL_MATRIX, &Ainv);CHKERRQ(ierr);
ierr = MatDestroy(&Ainvd);CHKERRQ(ierr);
#if 0
/* Symmetric version */
ierr = MatPtAP(Ainv, B, MAT_INITIAL_MATRIX, fill, S);CHKERRQ(ierr);
#else
/* Nonsymmetric version */
ierr = MatMatMatMult(C, Ainv, B, MAT_INITIAL_MATRIX, fill, S);CHKERRQ(ierr);
#endif
ierr = MatDestroy(&Ainv);CHKERRQ(ierr);
}
ierr = PetscViewerPushFormat(PETSC_VIEWER_STDOUT_WORLD, PETSC_VIEWER_ASCII_INFO);CHKERRQ(ierr);
ierr = MatView(*S, PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
ierr = PetscViewerPopFormat(PETSC_VIEWER_STDOUT_WORLD);CHKERRQ(ierr);
if (D) {
MatInfo info;
PetscReal norm;
ierr = MatGetInfo(D, MAT_GLOBAL_SUM, &info);CHKERRQ(ierr);
if (info.nz_used) {
ierr = MatNorm(D, NORM_INFINITY, &norm);CHKERRQ(ierr);
if (norm > PETSC_MACHINE_EPSILON) SETERRQ(PetscObjectComm((PetscObject) M), PETSC_ERR_SUP, "Not yet implemented for Schur complements with non-vanishing D");
}
}
PetscFunctionReturn(0);
}
PETSC_EXTERN void PETSC_STDCALL pcfactorgetmatrix_(PC pc,Mat *mat, int *__ierr ){
*__ierr = PCFactorGetMatrix(
(PC)PetscToPointer((pc) ),mat);
}
