void PETSc::Solve_withPureNeumann_LSQR(void)
{
ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
ierr = VecAssemblyBegin(x);
ierr = VecAssemblyEnd(x);
ierr = VecAssemblyBegin(b);
ierr = VecAssemblyEnd(b);
MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,PETSC_NULL,&nullsp);
KSPSetNullSpace(ksp,nullsp);
MatNullSpaceRemove(nullsp,b,PETSC_NULL);
KSPSetOperators(ksp,A,A,DIFFERENT_NONZERO_PATTERN);
KSPSetType(ksp,KSPLSQR);
//KSPGetPC(ksp, &pc);
//PCSetType(pc, PCASM);
KSPSetFromOptions(ksp);
KSPSetUp(ksp);
//start_clock("Before Petsc Solve in pure neumann solver");
KSPSolve(ksp,b,x);
//stop_clock("After Petsc Solve in pure neumann solver");
}
PetscErrorCode BSSCR_PCScGtKGAttachNullSpace( PC pc )
{
PC_SC_GtKG ctx = (PC_SC_GtKG)pc->data;
MatNullSpace nsp;
BSSCR_BSSCR_pc_error_ScGtKG( pc, __func__ );
/* Attach a null space */
MatNullSpaceCreate( PETSC_COMM_WORLD, PETSC_TRUE, PETSC_NULL, PETSC_NULL, &nsp );
#if ( (PETSC_VERSION_MAJOR >= 3) && (PETSC_VERSION_MINOR <6) )
KSPSetNullSpace( ctx->ksp_BBt, nsp );
#else
Mat A;
KSPGetOperators(ctx->ksp_BBt,&A,NULL);//Note: DOES NOT increase the reference counts of the matrix, so you should NOT destroy them.
MatSetNullSpace( A, nsp);
#endif
/*
NOTE: This does NOT destroy the memory for nsp, it just decrements the nsp->refct, so that
the next time MatNullSpaceDestroy() is called, the memory will be released. The next time this
is called will be by KSPDestroy();
*/
MatNullSpaceDestroy( nsp );
PetscFunctionReturn(0);
}
int main(int argc, char **argv)
{
Mat mat;
MatNullSpace nsp;
PetscBool prefix = PETSC_FALSE, flg;
PetscErrorCode ierr;
PetscInt zero = 0;
PetscScalar value = 0;
ierr = PetscInitialize(&argc, &argv, NULL, help); if (ierr) return ierr;
ierr = PetscOptionsGetBool(NULL, NULL, "-with_prefix",&prefix,NULL);CHKERRQ(ierr);
ierr = MatCreateDense(PETSC_COMM_WORLD, 1, 1, 1, 1, NULL, &mat);CHKERRQ(ierr);
ierr = MatSetOptionsPrefix(mat, prefix ? "prefix_" : NULL);CHKERRQ(ierr);
ierr = MatSetUp(mat);CHKERRQ(ierr);
ierr = MatSetValues(mat, 1, &zero, 1, &zero, &value, INSERT_VALUES);CHKERRQ(ierr);
ierr = MatAssemblyBegin(mat, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(mat, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD, PETSC_TRUE, 0, NULL, &nsp);CHKERRQ(ierr);
ierr = MatNullSpaceTest(nsp, mat, &flg);CHKERRQ(ierr);
if (!flg) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_PLIB,"Null space test failed!");
ierr = MatNullSpaceDestroy(&nsp);CHKERRQ(ierr);
ierr = MatDestroy(&mat);CHKERRQ(ierr);
ierr = PetscFinalize();
return ierr;
}
void PotentialSolve::SetupOperator(PotentialOp optype, double fval, vector<double> origin) {
//Set the matrix
switch (optype) {
case REALPBC :
_BuildCARTPBC();
MatNullSpaceCreate(PETSC_COMM_WORLD, PETSC_TRUE, 0, PETSC_NULL, &mnull);
break;
case CARTPBC :
_BuildCARTPBC(fval);
MatNullSpaceCreate(PETSC_COMM_WORLD, PETSC_TRUE, 0, PETSC_NULL, &mnull);
break;
case RADIAL :
_BuildRADIAL(fval, origin);
MatNullSpaceCreate(PETSC_COMM_WORLD, PETSC_TRUE, 0, PETSC_NULL, &mnull);
break;
default :
RAISE_ERR(99, "Unknown operator type");
}
// Sanity check
PetscTruth isNull;
MatNullSpaceTest(mnull, a, &isNull);
if (isNull != PETSC_TRUE) {
PetscPrintf(PETSC_COMM_WORLD, "Warning -- Null space is not truly a null space!\n");
}
PetscPrintf(PETSC_COMM_WORLD, "Completed operator initialization\n");
// Initialize the solver
KSPCreate(PETSC_COMM_WORLD,&solver);
KSPSetOperators(solver, a, a,SAME_PRECONDITIONER);
KSPSetTolerances(solver, rtol, atol, PETSC_DEFAULT, maxit);
// Set some defaults
KSPSetType(solver,KSPLGMRES);
KSPGMRESSetRestart(solver, 10);
// Possible for user to override
KSPSetFromOptions(solver);
// Set up the null space
KSPSetNullSpace(solver, mnull);
PetscPrintf(PETSC_COMM_WORLD, "Solver setup\n");
}
/*@C
DMMGSetNullSpace - Indicates the null space in the linear operator (this is needed by the linear solver)
Collective on DMMG
Input Parameter:
+ dmmg - the context
. has_cnst - is the constant vector in the null space
. n - number of null vectors (excluding the possible constant vector)
- func - a function that fills an array of vectors with the null vectors (must be orthonormal), may be PETSC_NULL
Level: advanced
.seealso DMMGCreate(), DMMGDestroy, DMMGSetDM(), DMMGSolve(), MatNullSpaceCreate(), KSPSetNullSpace(), DMMGSetMatType()
@*/
PetscErrorCode PETSCSNES_DLLEXPORT DMMGSetNullSpace(DMMG *dmmg,PetscTruth has_cnst,PetscInt n,PetscErrorCode (*func)(DMMG,Vec[]))
{
PetscErrorCode ierr;
PetscInt i,j,nlevels = dmmg[0]->nlevels;
Vec *nulls = 0;
MatNullSpace nullsp;
KSP iksp;
PC pc,ipc;
PetscTruth ismg,isred;
PetscFunctionBegin;
if (!dmmg) SETERRQ(PETSC_ERR_ARG_NULL,"Passing null as DMMG");
if (!dmmg[0]->ksp) SETERRQ(PETSC_ERR_ORDER,"Must call AFTER DMMGSetKSP() or DMMGSetSNES()");
if ((n && !func) || (!n && func)) SETERRQ(PETSC_ERR_ARG_INCOMP,"Both n and func() must be set together");
if (n < 0) SETERRQ1(PETSC_ERR_ARG_OUTOFRANGE,"Cannot have negative number of vectors in null space n = %D",n)
for (i=0; i<nlevels; i++) {
if (n) {
ierr = VecDuplicateVecs(dmmg[i]->b,n,&nulls);CHKERRQ(ierr);
ierr = (*func)(dmmg[i],nulls);CHKERRQ(ierr);
}
ierr = MatNullSpaceCreate(dmmg[i]->comm,has_cnst,n,nulls,&nullsp);CHKERRQ(ierr);
ierr = KSPSetNullSpace(dmmg[i]->ksp,nullsp);CHKERRQ(ierr);
for (j=i; j<nlevels; j++) {
ierr = KSPGetPC(dmmg[j]->ksp,&pc);CHKERRQ(ierr);
ierr = PetscTypeCompare((PetscObject)pc,PCMG,&ismg);CHKERRQ(ierr);
if (ismg) {
ierr = PCMGGetSmoother(pc,i,&iksp);CHKERRQ(ierr);
ierr = KSPSetNullSpace(iksp, nullsp);CHKERRQ(ierr);
}
}
ierr = MatNullSpaceDestroy(nullsp);CHKERRQ(ierr);
if (n) {
ierr = VecDestroyVecs(nulls,n);CHKERRQ(ierr);
}
}
/* make all the coarse grid solvers have LU shift since they are singular */
for (i=0; i<nlevels; i++) {
ierr = KSPGetPC(dmmg[i]->ksp,&pc);CHKERRQ(ierr);
ierr = PetscTypeCompare((PetscObject)pc,PCMG,&ismg);CHKERRQ(ierr);
if (ismg) {
ierr = PCMGGetSmoother(pc,0,&iksp);CHKERRQ(ierr);
ierr = KSPGetPC(iksp,&ipc);CHKERRQ(ierr);
ierr = PetscTypeCompare((PetscObject)ipc,PCREDUNDANT,&isred);CHKERRQ(ierr);
if (isred) {
ierr = PCRedundantGetPC(ipc,&ipc);CHKERRQ(ierr);
}
ierr = PCFactorSetShiftType(ipc,MAT_SHIFT_POSITIVE_DEFINITE);CHKERRQ(ierr);
}
}
PetscFunctionReturn(0);
}
void
SolverLinearPetsc<T>::setPetscConstantNullSpace()
{
if ( M_constant_null_space )
{
MatNullSpace nullsp;
MatNullSpaceCreate( PETSC_COMM_WORLD, PETSC_TRUE, 0, PETSC_NULL, &nullsp );
KSPSetNullSpace( M_ksp, nullsp );
PETSc::MatNullSpaceDestroy( nullsp );
}
}
int main(int argc, char **argv)
{
PetscErrorCode ierr;
Mat A;
KSP ksp;
PC pc;
IS zero, one;
MatNullSpace nullsp;
Vec x, b;
MPI_Comm comm;
PetscInitialize(&argc, &argv, NULL, NULL);
comm = PETSC_COMM_WORLD;
ierr = MatCreate(comm, &A);CHKERRQ(ierr);
ierr = MatSetSizes(A, 4, 4, PETSC_DECIDE, PETSC_DECIDE);CHKERRQ(ierr);
ierr = MatSetUp(A);CHKERRQ(ierr);
ierr = MatSetFromOptions(A);CHKERRQ(ierr);
ierr = MatCreateVecs(A, &x, &b);CHKERRQ(ierr);
ierr = VecSet(x, 2.0);CHKERRQ(ierr);
ierr = VecSet(b, 12.0);CHKERRQ(ierr);
ierr = MatDiagonalSet(A, x, INSERT_VALUES);CHKERRQ(ierr);
ierr = MatAssemblyBegin(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(A, MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = ISCreateStride(comm, 2, 0, 1, &zero);CHKERRQ(ierr);
ierr = ISCreateStride(comm, 2, 2, 1, &one);CHKERRQ(ierr);
ierr = MatNullSpaceCreate(comm, PETSC_TRUE, 0, NULL, &nullsp);CHKERRQ(ierr);
ierr = PetscObjectCompose((PetscObject)zero, "nullspace",(PetscObject)nullsp);CHKERRQ(ierr);
ierr = KSPCreate(comm, &ksp);CHKERRQ(ierr);
ierr = KSPSetOperators(ksp, A, A);CHKERRQ(ierr);
ierr = KSPSetUp(ksp);CHKERRQ(ierr);
ierr = KSPGetPC(ksp, &pc);CHKERRQ(ierr);
ierr = KSPSetFromOptions(ksp);CHKERRQ(ierr);
ierr = PCFieldSplitSetIS(pc, "0", zero);
ierr = PCFieldSplitSetIS(pc, "1", one);
ierr = KSPSolve(ksp, b, x);CHKERRQ(ierr);
ierr = KSPDestroy(&ksp);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nullsp);CHKERRQ(ierr);
ierr = ISDestroy(&zero);CHKERRQ(ierr);
ierr = ISDestroy(&one);CHKERRQ(ierr);
ierr = MatDestroy(&A);CHKERRQ(ierr);
ierr = VecDestroy(&x);CHKERRQ(ierr);
ierr = VecDestroy(&b);CHKERRQ(ierr);
PetscFinalize();
return 0;
}
PetscErrorCode ComputeRHS(KSP ksp,Vec b,void *ctx)
{
UserContext *user = (UserContext*)ctx;
PetscErrorCode ierr;
PetscInt i,j,mx,my,xm,ym,xs,ys;
PetscScalar Hx,Hy;
PetscScalar **array;
DM da;
PetscFunctionBeginUser;
ierr = KSPGetDM(ksp,&da);
CHKERRQ(ierr);
ierr = DMDAGetInfo(da, 0, &mx, &my, 0,0,0,0,0,0,0,0,0,0);
CHKERRQ(ierr);
Hx = 1.0 / (PetscReal)(mx-1);
Hy = 1.0 / (PetscReal)(my-1);
ierr = DMDAGetCorners(da,&xs,&ys,0,&xm,&ym,0);
CHKERRQ(ierr);
ierr = DMDAVecGetArray(da, b, &array);
CHKERRQ(ierr);
for (j=ys; j<ys+ym; j++) {
for (i=xs; i<xs+xm; i++) {
array[j][i] = PetscExpScalar(-((PetscReal)i*Hx)*((PetscReal)i*Hx)/user->nu)*PetscExpScalar(-((PetscReal)j*Hy)*((PetscReal)j*Hy)/user->nu)*Hx*Hy;
}
}
ierr = DMDAVecRestoreArray(da, b, &array);
CHKERRQ(ierr);
ierr = VecAssemblyBegin(b);
CHKERRQ(ierr);
ierr = VecAssemblyEnd(b);
CHKERRQ(ierr);
/* force right hand side to be consistent for singular matrix */
/* note this is really a hack, normally the model would provide you with a consistent right handside */
if (user->bcType == NEUMANN) {
MatNullSpace nullspace;
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace);
CHKERRQ(ierr);
ierr = MatNullSpaceRemove(nullspace,b,PETSC_NULL);
CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nullspace);
CHKERRQ(ierr);
}
PetscFunctionReturn(0);
}
PetscErrorCode ComputeRHS(KSP ksp,Vec b,void *ctx)
{
UserContext *user = (UserContext*)ctx;
PetscErrorCode ierr;
PetscInt i, j, M, N, xm ,ym ,xs, ys;
PetscScalar Hx, Hy, pi, uu, tt;
PetscScalar **array;
DM da;
PetscFunctionBeginUser;
ierr = KSPGetDM(ksp,&da);CHKERRQ(ierr);
ierr = DMDAGetInfo(da, 0, &M, &N, 0,0,0,0,0,0,0,0,0,0);CHKERRQ(ierr);
uu = user->uu; tt = user->tt;
pi = 4*atan(1.0);
Hx = 1.0/(PetscReal)(M);
Hy = 1.0/(PetscReal)(N);
ierr = DMDAGetCorners(da,&xs,&ys,0,&xm,&ym,0);CHKERRQ(ierr); // Fine grid
//printf(" M N: %d %d; xm ym: %d %d; xs ys: %d %d\n",M,N,xm,ym,xs,ys);
ierr = DMDAVecGetArray(da, b, &array);CHKERRQ(ierr);
for (j=ys; j<ys+ym; j++){
for (i=xs; i<xs+xm; i++){
array[j][i] = -PetscCosScalar(uu*pi*((PetscReal)i+0.5)*Hx)*cos(tt*pi*((PetscReal)j+0.5)*Hy)*Hx*Hy;
}
}
ierr = DMDAVecRestoreArray(da, b, &array);CHKERRQ(ierr);
ierr = VecAssemblyBegin(b);CHKERRQ(ierr);
ierr = VecAssemblyEnd(b);CHKERRQ(ierr);
/* force right hand side to be consistent for singular matrix */
/* note this is really a hack, normally the model would provide you with a consistent right handside */
if (user->bcType == NEUMANN) {
MatNullSpace nullspace;
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace);CHKERRQ(ierr);
ierr = MatNullSpaceRemove(nullspace,b,PETSC_NULL);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nullspace);CHKERRQ(ierr);
}
PetscFunctionReturn(0);
}
PetscErrorCode ComputeRHS(KSP ksp,Vec b,void *ctx)
{
PetscErrorCode ierr;
PetscInt i,j,k,mx,my,mz,xm,ym,zm,xs,ys,zs;
PetscScalar Hx,Hy,Hz;
PetscScalar ***array;
DM da;
MatNullSpace nullspace;
PetscFunctionBeginUser;
ierr = KSPGetDM(ksp,&da);CHKERRQ(ierr);
ierr = DMDAGetInfo(da, 0, &mx, &my, &mz, 0,0,0,0,0,0,0,0,0);CHKERRQ(ierr);
Hx = 1.0 / (PetscReal)(mx);
Hy = 1.0 / (PetscReal)(my);
Hz = 1.0 / (PetscReal)(mz);
ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr);
ierr = DMDAVecGetArray(da, b, &array);CHKERRQ(ierr);
for (k=zs; k<zs+zm; k++) {
for (j=ys; j<ys+ym; j++) {
for (i=xs; i<xs+xm; i++) {
array[k][j][i] = 12 * PETSC_PI * PETSC_PI
* PetscCosScalar(2*PETSC_PI*(((PetscReal)i+0.5)*Hx))
* PetscCosScalar(2*PETSC_PI*(((PetscReal)j+0.5)*Hy))
* PetscCosScalar(2*PETSC_PI*(((PetscReal)k+0.5)*Hz))
* Hx * Hy * Hz;
}
}
}
ierr = DMDAVecRestoreArray(da, b, &array);CHKERRQ(ierr);
ierr = VecAssemblyBegin(b);CHKERRQ(ierr);
ierr = VecAssemblyEnd(b);CHKERRQ(ierr);
/* force right hand side to be consistent for singular matrix */
/* note this is really a hack, normally the model would provide you with a consistent right handside */
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace);CHKERRQ(ierr);
ierr = MatNullSpaceRemove(nullspace,b);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nullspace);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
void PETSc::Solve_withPureNeumann(void)
{
ierr = MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
ierr = MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
ierr = VecAssemblyBegin(x);
ierr = VecAssemblyEnd(x);
ierr = VecAssemblyBegin(b);
ierr = VecAssemblyEnd(b);
MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,PETSC_NULL,&nullsp);
KSPSetNullSpace(ksp,nullsp);
KSPSetOperators(ksp,A,A,DIFFERENT_NONZERO_PATTERN);
//KSPSetType(ksp,KSPMINRES);
//KSPSetType(ksp,KSPGMRES);
//KSPSetType(ksp,KSPBCGS);
KSPSetType(ksp,KSPBCGSL);
KSPBCGSLSetEll(ksp,2);
//KSPGetPC(ksp, &pc);
//PCSetType(pc, PCASM);
//PCSetType(pc, PCMG);
//PCMGSetLevels(pc, 3, &PETSC_COMM_WORLD);
//PCMGSetType(pc,PC_MG_MULTIPLICATIVE);
//PCMGSetCycleType(pc,PC_MG_CYCLE_V);
//
KSPSetFromOptions(ksp);
KSPSetUp(ksp);
//start_clock("Before Petsc Solve in pure neumann solver");
KSPSolve(ksp,b,x);
//stop_clock("After Petsc Solve in pure neumann solver");
}
PetscErrorCode ComputeJacobian(KSP ksp,Mat J, Mat jac,void *ctx)
{
PetscErrorCode ierr;
PetscInt i, j, M, N, xm, ym, xs, ys;
PetscScalar v[5], Hx, Hy, HydHx, HxdHy;
MatStencil row, col[5];
DM da;
MatNullSpace nullspace;
PetscFunctionBeginUser;
ierr = KSPGetDM(ksp,&da);CHKERRQ(ierr);
ierr = DMDAGetInfo(da,0,&M,&N,0,0,0,0,0,0,0,0,0,0);CHKERRQ(ierr);
Hx = 1.0 / (PetscReal)(M);
Hy = 1.0 / (PetscReal)(N);
HxdHy = Hx/Hy;
HydHx = Hy/Hx;
ierr = DMDAGetCorners(da,&xs,&ys,0,&xm,&ym,0);CHKERRQ(ierr);
for (j=ys; j<ys+ym; j++) {
for (i=xs; i<xs+xm; i++) {
row.i = i; row.j = j;
v[0] = -HxdHy; col[0].i = i; col[0].j = j-1;
v[1] = -HydHx; col[1].i = i-1; col[1].j = j;
v[2] = 2.0*(HxdHy + HydHx); col[2].i = i; col[2].j = j;
v[3] = -HydHx; col[3].i = i+1; col[3].j = j;
v[4] = -HxdHy; col[4].i = i; col[4].j = j+1;
ierr = MatSetValuesStencil(jac,1,&row,5,col,v,ADD_VALUES);CHKERRQ(ierr);
}
}
ierr = MatAssemblyBegin(jac,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(jac,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace);CHKERRQ(ierr);
ierr = MatSetNullSpace(J,nullspace);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nullspace);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
PetscErrorCode ComputeRHS(DM da, Vec b, PetscScalar nu)
{
PetscErrorCode ierr;
PetscInt i, j, mx, my, xm, ym, xs, ys;
PetscScalar Hx, Hy;
PetscScalar** array;
PetscFunctionBeginUser;
ierr = DMDAGetInfo(da, 0, &mx, &my, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
CHKERRQ(ierr);
Hx = 1.0 / (PetscReal)(mx);
Hy = 1.0 / (PetscReal)(my);
ierr = DMDAGetCorners(da, &xs, &ys, 0, &xm, &ym, 0);
CHKERRQ(ierr);
ierr = DMDAVecGetArray(da, b, &array);
CHKERRQ(ierr);
for (j = ys; j < ys + ym; j++) {
for (i = xs; i < xs + xm; i++) {
array[j][i] = PetscExpScalar(-(((PetscReal)i + 0.5) * Hx) * (((PetscReal)i + 0.5) * Hx) / nu) *
PetscExpScalar(-(((PetscReal)j + 0.5) * Hy) * (((PetscReal)j + 0.5) * Hy) / nu) * Hx * Hy * nu;
}
}
ierr = DMDAVecRestoreArray(da, b, &array);
CHKERRQ(ierr);
ierr = VecAssemblyBegin(b);
CHKERRQ(ierr);
ierr = VecAssemblyEnd(b);
CHKERRQ(ierr);
MatNullSpace nullspace;
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD, PETSC_TRUE, 0, 0, &nullspace);
CHKERRQ(ierr);
ierr = MatNullSpaceRemove(nullspace, b);
CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nullspace);
CHKERRQ(ierr);
PetscFunctionReturn(0);
}
PetscErrorCode ComputeMatrix(KSP ksp, Mat J,Mat jac, void *ctx)
{
PetscErrorCode ierr;
PetscInt i,j,k,mx,my,mz,xm,ym,zm,xs,ys,zs,num, numi, numj, numk;
PetscScalar v[7],Hx,Hy,Hz,HyHzdHx,HxHzdHy,HxHydHz;
MatStencil row, col[7];
DM da;
MatNullSpace nullspace;
PetscFunctionBeginUser;
ierr = KSPGetDM(ksp,&da);CHKERRQ(ierr);
ierr = DMDAGetInfo(da,0,&mx,&my,&mz,0,0,0,0,0,0,0,0,0);CHKERRQ(ierr);
Hx = 1.0 / (PetscReal)(mx);
Hy = 1.0 / (PetscReal)(my);
Hz = 1.0 / (PetscReal)(mz);
HyHzdHx = Hy*Hz/Hx;
HxHzdHy = Hx*Hz/Hy;
HxHydHz = Hx*Hy/Hz;
ierr = DMDAGetCorners(da,&xs,&ys,&zs,&xm,&ym,&zm);CHKERRQ(ierr);
for (k=zs; k<zs+zm; k++) {
for (j=ys; j<ys+ym; j++) {
for (i=xs; i<xs+xm; i++) {
row.i = i; row.j = j; row.k = k;
if (i==0 || j==0 || k==0 || i==mx-1 || j==my-1 || k==mz-1) {
num = 0; numi=0; numj=0; numk=0;
if (k!=0) {
v[num] = -HxHydHz;
col[num].i = i;
col[num].j = j;
col[num].k = k-1;
num++; numk++;
}
if (j!=0) {
v[num] = -HxHzdHy;
col[num].i = i;
col[num].j = j-1;
col[num].k = k;
num++; numj++;
}
if (i!=0) {
v[num] = -HyHzdHx;
col[num].i = i-1;
col[num].j = j;
col[num].k = k;
num++; numi++;
}
if (i!=mx-1) {
v[num] = -HyHzdHx;
col[num].i = i+1;
col[num].j = j;
col[num].k = k;
num++; numi++;
}
if (j!=my-1) {
v[num] = -HxHzdHy;
col[num].i = i;
col[num].j = j+1;
col[num].k = k;
num++; numj++;
}
if (k!=mz-1) {
v[num] = -HxHydHz;
col[num].i = i;
col[num].j = j;
col[num].k = k+1;
num++; numk++;
}
v[num] = (PetscReal)(numk)*HxHydHz + (PetscReal)(numj)*HxHzdHy + (PetscReal)(numi)*HyHzdHx;
col[num].i = i; col[num].j = j; col[num].k = k;
num++;
ierr = MatSetValuesStencil(jac,1,&row,num,col,v,INSERT_VALUES);CHKERRQ(ierr);
} else {
v[0] = -HxHydHz; col[0].i = i; col[0].j = j; col[0].k = k-1;
v[1] = -HxHzdHy; col[1].i = i; col[1].j = j-1; col[1].k = k;
v[2] = -HyHzdHx; col[2].i = i-1; col[2].j = j; col[2].k = k;
v[3] = 2.0*(HyHzdHx + HxHzdHy + HxHydHz); col[3].i = i; col[3].j = j; col[3].k = k;
v[4] = -HyHzdHx; col[4].i = i+1; col[4].j = j; col[4].k = k;
v[5] = -HxHzdHy; col[5].i = i; col[5].j = j+1; col[5].k = k;
v[6] = -HxHydHz; col[6].i = i; col[6].j = j; col[6].k = k+1;
ierr = MatSetValuesStencil(jac,1,&row,7,col,v,INSERT_VALUES);CHKERRQ(ierr);
}
}
}
}
ierr = MatAssemblyBegin(jac,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(jac,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace);CHKERRQ(ierr);
ierr = MatSetNullSpace(jac,nullspace);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nullspace);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
PetscErrorCode computeMatrix2D(KSP ksp, Mat A, Mat pc, MatStructure * matStructure,
void* ctx){
PetscUserCtx* context = (PetscUserCtx*) ctx;
Parameters & parameters = context -> getParameters();
IntScalarField & flags = context->getFlowField().getFlags();
int *limitsX, *limitsY, *limitsZ;
context->getLimits(&limitsX, &limitsY, &limitsZ);
PetscScalar dx = parameters.geometry.dx,
dy = parameters.geometry.dy;
PetscScalar stencilValues[5];
MatStencil row, column[5];
PetscInt i, j, Nx, Ny;
Nx = parameters.geometry.sizeX + 2;
Ny = parameters.geometry.sizeY + 2;
// Loop for inner nodes
for (j = limitsY[0]; j < limitsY[1]; j++){
for (i = limitsX[0]; i < limitsX[1]; i++){
row.i = i; row.j = j;
const int obstacle = flags.getValue(i-limitsX[0]+2, j-limitsY[0]+2);
if ((obstacle & OBSTACLE_SELF) == 0) { // If we have a fluid cell
// Definition of values
stencilValues[0] = 1/(dx*dx);
stencilValues[1] = 1/(dx*dx);
stencilValues[2] = -(2.0/(dx*dx) + 2.0/(dy*dy));
stencilValues[3] = 1/(dy*dy);
stencilValues[4] = 1/(dy*dy);
// Definition of positions. Order must correspond to values
column[0].i = i+1; column[0].j = j;
column[1].i = i-1; column[1].j = j;
column[2].i = i; column[2].j = j;
column[3].i = i; column[3].j = j+1;
column[4].i = i; column[4].j = j-1;
MatSetValuesStencil(A, 1, &row, 5, column, stencilValues, INSERT_VALUES);
} else if (obstacle != OBSTACLE_SELF + OBSTACLE_LEFT + OBSTACLE_RIGHT + OBSTACLE_TOP +
OBSTACLE_BOTTOM) { // Not fluid, but fluid somewhere around
int counter = 0; // This will contain how many neighbours are fluid
if ((obstacle & OBSTACLE_LEFT) == 0){ // If there is fluid to the left
stencilValues[counter] = 1.0;
column[counter].i = i-1; column[counter].j = j;
counter++; // We have just identified a fuid cell and prepared to average
}
if ((obstacle & OBSTACLE_RIGHT) == 0){
stencilValues[counter] = 1.0;
column[counter].i = i+1; column[counter].j = j;
counter++;
}
if ((obstacle & OBSTACLE_BOTTOM) == 0){
stencilValues[counter] = 1.0;
column[counter].i = i; column[counter].j = j-1;
counter++;
}
if ((obstacle & OBSTACLE_TOP) == 0){
stencilValues[counter] = 1.0;
column[counter].i = i; column[counter].j = j+1;
counter++;
}
// A column for the cell itself
stencilValues[counter] = (double)(-counter);
column[counter].i = i; column[counter].j = j;
// Once we identified how many fluid cells are around and set columns for each, we
// enter the row into the matrix.
MatSetValuesStencil(A, 1, &row, counter+1, column, stencilValues, INSERT_VALUES);
} else { // The remaining possibility is that the cell is obstacle surrounded
// by more obstacle cells
// Here, we just add an equation to set the value according to the right hand side
stencilValues[0] = 1.0;
column[0].i = i; column[0].j = j;
MatSetValuesStencil(A, 1, &row, 1, column, stencilValues, INSERT_VALUES);
}
}
}
// Left wall
if (context->setAsBoundary & LEFT_WALL_BIT){
for (j = limitsY[0]; j < limitsY[1]; j++){
column[0].i = 0; column[0].j = j;
column[1].i = context->displacement[0]; column[1].j = j;
row.i = 0; row.j = j;
if (parameters.walls.typeLeft == DIRICHLET){ // If Dirichlet velocity boundary conditions
// therefore, Neumann in the pressure
stencilValues[0] = 1;
stencilValues[1] = -1;
} else if (parameters.walls.typeLeft == NEUMANN){ // Neumann velocity boundary conditions,
stencilValues[0] = 0.5;
stencilValues[1] = 0.5;
}
MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES);
}
}
// Right wall
if (context->setAsBoundary & RIGHT_WALL_BIT){
for (j = limitsY[0]; j < limitsY[1]; j++){
column[0].i = Nx-1; column[0].j = j;
column[1].i = context->displacement[1]; column[1].j = j;
row.i = Nx-1; row.j = j;
if (parameters.walls.typeRight == DIRICHLET){
stencilValues[0] = 1;
stencilValues[1] = -1;
} else if (parameters.walls.typeRight == NEUMANN){
stencilValues[0] = 0.5;
stencilValues[1] = 0.5;
}
MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES);
}
}
// Bottom wall
if (context->setAsBoundary & BOTTOM_WALL_BIT){
for (i = limitsX[0]; i < limitsX[1]; i++){
column[0].i = i; column[0].j = 0;
column[1].i = i; column[1].j = context->displacement[2];
row.i = i; row.j = 0;
if (parameters.walls.typeBottom == DIRICHLET){
stencilValues[0] = 1;
stencilValues[1] = -1;
} else if (parameters.walls.typeBottom == NEUMANN) {
stencilValues[0] = 0.5;
stencilValues[1] = 0.5;
}
MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES);
}
}
// Top wall
if (context->setAsBoundary & TOP_WALL_BIT){
for (i = limitsX[0]; i < limitsX[1]; i++){
column[0].i = i; column[0].j = Ny-1;
column[1].i = i; column[1].j = context->displacement[3];
row.i = i; row.j = Ny-1;
if (parameters.walls.typeTop == DIRICHLET){
stencilValues[0] = 1;
stencilValues[1] = -1;
} else if (parameters.walls.typeTop == NEUMANN) {
stencilValues[0] = 0.5;
stencilValues[1] = 0.5;
}
MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES);
}
}
MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
MatNullSpace nullspace;
MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace);
MatSetNullSpace(A,nullspace);
MatNullSpaceDestroy(&nullspace);
return 0;
}
PetscErrorCode computeMatrix3D(KSP ksp, Mat A, Mat pc, MatStructure * matStructure,
void* ctx){
PetscUserCtx* context = (PetscUserCtx*) ctx;
Parameters & parameters = context -> getParameters();
IntScalarField & flags = context->getFlowField().getFlags();
int *limitsX, *limitsY, *limitsZ;
context->getLimits(&limitsX, &limitsY, &limitsZ);
PetscScalar dx = parameters.geometry.dx,
dy = parameters.geometry.dy,
dz = parameters.geometry.dz;
PetscScalar stencilValues[7];
MatStencil row, column[7];
PetscInt i, j, k, Nx, Ny, Nz;
Nx = parameters.geometry.sizeX + 2;
Ny = parameters.geometry.sizeY + 2;
Nz = parameters.geometry.sizeZ + 2;
// Loop for inner nodes
for (k = limitsZ[0]; k < limitsZ[1]; k++){
for (j = limitsY[0]; j < limitsY[1]; j++){
for (i = limitsX[0]; i < limitsX[1]; i++){
row.i = i; row.j = j, row.k = k;
const int obstacle = flags.getValue(i-limitsX[0]+2, j-limitsY[0]+2, k-limitsZ[0]+2);
if ((obstacle & OBSTACLE_SELF) == 0) { // If the cell is fluid
// Definition of values
stencilValues[0] = 1/(dx*dx);
stencilValues[1] = 1/(dx*dx);
stencilValues[2] = 1/(dy*dy);
stencilValues[3] = 1/(dy*dy);
stencilValues[4] = 1/(dz*dz);
stencilValues[5] = 1/(dz*dz);
stencilValues[6] = -(2.0/(dx*dx) + 2.0/(dy*dy) + 2.0/(dz*dz));
// Definition of positions. Order must correspond to values
column[0].i = i+1; column[0].j = j; column[0].k = k;
column[1].i = i-1; column[1].j = j; column[1].k = k;
column[2].i = i; column[2].j = j+1; column[2].k = k;
column[3].i = i; column[3].j = j-1; column[3].k = k;
column[4].i = i; column[4].j = j; column[4].k = k+1;
column[5].i = i; column[5].j = j; column[5].k = k-1;
column[6].i = i; column[6].j = j; column[6].k = k;
MatSetValuesStencil(A, 1, &row, 7, column, stencilValues, INSERT_VALUES);
} else if (obstacle != 127) { // If non-fluid and still not completely surounded
int counter = 0;
if ((obstacle & OBSTACLE_LEFT) == 0){ // If there's fluid to the left
stencilValues[counter] = 1;
column[counter].i = i-1; column[counter].j = j, column[counter].k = k;
counter++;
}
if ((obstacle & OBSTACLE_RIGHT) == 0){
stencilValues[counter] = 1;
column[counter].i = i+1; column[counter].j = j, column[counter].k = k;
counter++;
}
if ((obstacle & OBSTACLE_BOTTOM) == 0){
stencilValues[counter] = 1;
column[counter].i = i; column[counter].j = j-1, column[counter].k = k;
counter++;
}
if ((obstacle & OBSTACLE_TOP) == 0){
stencilValues[counter] = 1;
column[counter].i = i; column[counter].j = j+1, column[counter].k = k;
counter++;
}
if ((obstacle & OBSTACLE_FRONT) == 0){
stencilValues[counter] = 1;
column[counter].i = i; column[counter].j = j, column[counter].k = k-1;
counter++;
}
if ((obstacle & OBSTACLE_BACK) == 0){
stencilValues[counter] = 1;
column[counter].i = i; column[counter].j = j, column[counter].k = k+1;
counter++;
}
// Now set a line for the element itself
stencilValues[counter] = (double)(-counter);
column[counter].i = i; column[counter].j = j, column[counter].k = k;
MatSetValuesStencil(A, 1, &row, counter+1, column, stencilValues, INSERT_VALUES);
} else { // If the cell is an inner obstacle cell
stencilValues[0] = 1.0;
column[0].i = i; column[0].j = j; column[0].k = k;
MatSetValuesStencil(A, 1, &row, 1, column, stencilValues, INSERT_VALUES);
}
}
}
}
// Left wall
if (context->setAsBoundary & LEFT_WALL_BIT){
for (j = limitsY[0]; j < limitsY[1]; j++){
for (k = limitsZ[0]; k < limitsZ[1]; k++){
column[0].i = 0; column[0].j = j; column[0].k = k;
column[1].i = context->displacement[0]; column[1].j = j; column[1].k = k;
row.i = 0; row.j = j; row.k = k;
if (parameters.walls.typeLeft == DIRICHLET){
stencilValues[0] = 1;
stencilValues[1] = -1;
} else if (parameters.walls.typeLeft == NEUMANN){
stencilValues[0] = 0.5;
stencilValues[1] = 0.5;
}
MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES);
}
}
}
// Right wall
if (context->setAsBoundary & RIGHT_WALL_BIT){
for (j = limitsY[0]; j < limitsY[1]; j++){
for (k = limitsZ[0]; k < limitsZ[1]; k++){
column[0].i = Nx-1; column[0].j = j; column[0].k = k;
column[1].i = context->displacement[1]; column[1].j = j; column[1].k = k;
row.i = Nx-1; row.j = j; row.k = k;
if (parameters.walls.typeRight == DIRICHLET){
stencilValues[0] = 1;
stencilValues[1] = -1;
} else if (parameters.walls.typeRight == NEUMANN){
stencilValues[0] = 0.5;
stencilValues[1] = 0.5;
}
MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES);
}
}
}
// Bottom wall
if (context->setAsBoundary & BOTTOM_WALL_BIT){
for (i = limitsX[0]; i < limitsX[1]; i++){
for (k = limitsZ[0]; k < limitsZ[1]; k++){
column[0].i = i; column[0].j = 0; column[0].k = k;
column[1].i = i; column[1].j = context->displacement[2]; column[1].k = k;
row.i = i; row.j = 0; row.k = k;
if (parameters.walls.typeBottom == DIRICHLET){
stencilValues[0] = 1;
stencilValues[1] = -1;
} else if (parameters.walls.typeBottom == NEUMANN){
stencilValues[0] = 0.5;
stencilValues[1] = 0.5;
}
MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES);
}
}
}
// Top wall
if (context->setAsBoundary & TOP_WALL_BIT){
for (i = limitsX[0]; i < limitsX[1]; i++){
for (k = limitsZ[0]; k < limitsZ[1]; k++){
column[0].i = i; column[0].j = Ny-1; column[0].k = k;
column[1].i = i; column[1].j = context->displacement[3]; column[1].k = k;
row.i = i; row.j = Ny-1; row.k = k;
if (parameters.walls.typeTop == DIRICHLET){
stencilValues[0] = 1;
stencilValues[1] = -1;
} else if (parameters.walls.typeTop == NEUMANN){
stencilValues[0] = 0.5;
stencilValues[1] = 0.5;
}
MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES);
}
}
}
// Front wall
if (context->setAsBoundary & FRONT_WALL_BIT){
for (i = limitsX[0]; i < limitsX[1]; i++){
for (j = limitsY[0]; j < limitsY[1]; j++){
column[0].i = i; column[0].j = j; column[0].k = 0;
column[1].i = i; column[1].j = j; column[1].k = context->displacement[4];
row.i = i; row.j = j; row.k = 0;
if (parameters.walls.typeFront == DIRICHLET){
stencilValues[0] = 1;
stencilValues[1] = -1;
} else if (parameters.walls.typeFront == NEUMANN){
stencilValues[0] = 0.5;
stencilValues[1] = 0.5;
}
MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES);
}
}
}
// Back wall
if (context->setAsBoundary & BACK_WALL_BIT){
for (i = limitsX[0]; i < limitsX[1]; i++){
for (j = limitsY[0]; j < limitsY[1]; j++){
column[0].i = i; column[0].j = j; column[0].k = Nz-1;
column[1].i = i; column[1].j = j; column[1].k = context->displacement[5];
row.i = i; row.j = j; row.k = Nz-1;
if (parameters.walls.typeBack == DIRICHLET){
stencilValues[0] = 1;
stencilValues[1] = -1;
} else if (parameters.walls.typeBack == NEUMANN){
stencilValues[0] = 0.5;
stencilValues[1] = 0.5;
}
MatSetValuesStencil(A, 1, &row, 2, column, stencilValues, INSERT_VALUES);
}
}
}
MatAssemblyBegin(A,MAT_FINAL_ASSEMBLY);
MatAssemblyEnd(A,MAT_FINAL_ASSEMBLY);
MatNullSpace nullspace;
MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace);
MatSetNullSpace(A,nullspace);
MatNullSpaceDestroy(&nullspace);
return 0;
}
PetscErrorCode ComputeJacobian(KSP ksp,Mat J, Mat jac,MatStructure *str,void *ctx)
{
UserContext *user = (UserContext*)ctx;
PetscErrorCode ierr;
PetscInt i, j, M, N, xm, ym, xs, ys, num, numi, numj;
PetscScalar v[5], Hx, Hy, HydHx, HxdHy;
MatStencil row, col[5];
DM da;
PetscFunctionBeginUser;
ierr = KSPGetDM(ksp,&da);CHKERRQ(ierr);
ierr = DMDAGetInfo(da,0,&M,&N,0,0,0,0,0,0,0,0,0,0);CHKERRQ(ierr);
Hx = 1.0 / (PetscReal)(M);
Hy = 1.0 / (PetscReal)(N);
HxdHy = Hx/Hy;
HydHx = Hy/Hx;
ierr = DMDAGetCorners(da,&xs,&ys,0,&xm,&ym,0);CHKERRQ(ierr);
for (j=ys; j<ys+ym; j++){
for (i=xs; i<xs+xm; i++){
row.i = i; row.j = j;
if (i==0 || j==0 || i==M-1 || j==N-1) {
if (user->bcType == DIRICHLET){
SETERRQ(PETSC_COMM_SELF,PETSC_ERR_SUP,"Dirichlet boundary conditions not supported !\n");
} else if (user->bcType == NEUMANN){
num=0; numi=0; numj=0;
if (j!=0) {
v[num] = -HxdHy; col[num].i = i; col[num].j = j-1;
num++; numj++;
}
if (i!=0) {
v[num] = -HydHx; col[num].i = i-1; col[num].j = j;
num++; numi++;
}
if (i!=M-1) {
v[num] = -HydHx; col[num].i = i+1; col[num].j = j;
num++; numi++;
}
if (j!=N-1) {
v[num] = -HxdHy; col[num].i = i; col[num].j = j+1;
num++; numj++;
}
v[num] = ( (PetscReal)(numj)*HxdHy + (PetscReal)(numi)*HydHx ); col[num].i = i; col[num].j = j;
num++;
ierr = MatSetValuesStencil(jac,1,&row,num,col,v,INSERT_VALUES);CHKERRQ(ierr);
}
} else {
v[0] = -HxdHy; col[0].i = i; col[0].j = j-1;
v[1] = -HydHx; col[1].i = i-1; col[1].j = j;
v[2] = 2.0*(HxdHy + HydHx); col[2].i = i; col[2].j = j;
v[3] = -HydHx; col[3].i = i+1; col[3].j = j;
v[4] = -HxdHy; col[4].i = i; col[4].j = j+1;
ierr = MatSetValuesStencil(jac,1,&row,5,col,v,INSERT_VALUES);CHKERRQ(ierr);
}
}
}
ierr = MatAssemblyBegin(jac,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(jac,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
if (user->bcType == NEUMANN) {
MatNullSpace nullspace;
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,0,&nullspace);CHKERRQ(ierr);
ierr = MatSetNullSpace(jac,nullspace);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nullspace);CHKERRQ(ierr);
}
PetscFunctionReturn(0);
}
PetscErrorCode PCISSetUp(PC pc)
{
PC_IS *pcis = (PC_IS*)(pc->data);
Mat_IS *matis;
PetscErrorCode ierr;
PetscBool flg,issbaij;
Vec counter;
PetscFunctionBegin;
ierr = PetscObjectTypeCompare((PetscObject)pc->pmat,MATIS,&flg);CHKERRQ(ierr);
if (!flg) SETERRQ(PetscObjectComm((PetscObject)pc),PETSC_ERR_ARG_WRONG,"Preconditioner type of Neumann Neumman requires matrix of type MATIS");
matis = (Mat_IS*)pc->pmat->data;
pcis->pure_neumann = matis->pure_neumann;
/* get info on mapping */
ierr = PetscObjectReference((PetscObject)matis->mapping);CHKERRQ(ierr);
ierr = ISLocalToGlobalMappingDestroy(&pcis->mapping);CHKERRQ(ierr);
pcis->mapping = matis->mapping;
ierr = ISLocalToGlobalMappingGetSize(pcis->mapping,&pcis->n);CHKERRQ(ierr);
ierr = ISLocalToGlobalMappingGetInfo(pcis->mapping,&(pcis->n_neigh),&(pcis->neigh),&(pcis->n_shared),&(pcis->shared));CHKERRQ(ierr);
/* Creating local and global index sets for interior and inteface nodes. */
{
PetscInt n_I;
PetscInt *idx_I_local,*idx_B_local,*idx_I_global,*idx_B_global;
PetscInt *array;
PetscInt i,j;
/* Identifying interior and interface nodes, in local numbering */
ierr = PetscMalloc1(pcis->n,&array);CHKERRQ(ierr);
ierr = PetscMemzero(array,pcis->n*sizeof(PetscInt));CHKERRQ(ierr);
for (i=0;i<pcis->n_neigh;i++)
for (j=0;j<pcis->n_shared[i];j++)
array[pcis->shared[i][j]] += 1;
ierr = PetscMalloc1(pcis->n,&idx_I_local);CHKERRQ(ierr);
ierr = PetscMalloc1(pcis->n,&idx_B_local);CHKERRQ(ierr);
for (i=0, pcis->n_B=0, n_I=0; i<pcis->n; i++) {
if (!array[i]) {
idx_I_local[n_I] = i;
n_I++;
} else {
idx_B_local[pcis->n_B] = i;
pcis->n_B++;
}
}
/* Getting the global numbering */
idx_B_global = idx_I_local + n_I; /* Just avoiding allocating extra memory, since we have vacant space */
idx_I_global = idx_B_local + pcis->n_B;
ierr = ISLocalToGlobalMappingApply(pcis->mapping,pcis->n_B,idx_B_local,idx_B_global);CHKERRQ(ierr);
ierr = ISLocalToGlobalMappingApply(pcis->mapping,n_I, idx_I_local,idx_I_global);CHKERRQ(ierr);
/* Creating the index sets. */
ierr = ISCreateGeneral(PETSC_COMM_SELF,pcis->n_B,idx_B_local,PETSC_COPY_VALUES, &pcis->is_B_local);CHKERRQ(ierr);
ierr = ISCreateGeneral(PETSC_COMM_SELF,pcis->n_B,idx_B_global,PETSC_COPY_VALUES,&pcis->is_B_global);CHKERRQ(ierr);
ierr = ISCreateGeneral(PETSC_COMM_SELF,n_I,idx_I_local,PETSC_COPY_VALUES, &pcis->is_I_local);CHKERRQ(ierr);
ierr = ISCreateGeneral(PETSC_COMM_SELF,n_I,idx_I_global,PETSC_COPY_VALUES,&pcis->is_I_global);CHKERRQ(ierr);
/* Freeing memory and restoring arrays */
ierr = PetscFree(idx_B_local);CHKERRQ(ierr);
ierr = PetscFree(idx_I_local);CHKERRQ(ierr);
ierr = PetscFree(array);CHKERRQ(ierr);
}
/*
Extracting the blocks A_II, A_BI, A_IB and A_BB from A. If the numbering
is such that interior nodes come first than the interface ones, we have
[ | ]
[ A_II | A_IB ]
A = [ | ]
[-----------+------]
[ A_BI | A_BB ]
*/
ierr = MatGetSubMatrix(matis->A,pcis->is_I_local,pcis->is_I_local,MAT_INITIAL_MATRIX,&pcis->A_II);CHKERRQ(ierr);
ierr = MatGetSubMatrix(matis->A,pcis->is_B_local,pcis->is_B_local,MAT_INITIAL_MATRIX,&pcis->A_BB);CHKERRQ(ierr);
ierr = PetscObjectTypeCompare((PetscObject)matis->A,MATSEQSBAIJ,&issbaij);CHKERRQ(ierr);
if (!issbaij) {
ierr = MatGetSubMatrix(matis->A,pcis->is_I_local,pcis->is_B_local,MAT_INITIAL_MATRIX,&pcis->A_IB);CHKERRQ(ierr);
ierr = MatGetSubMatrix(matis->A,pcis->is_B_local,pcis->is_I_local,MAT_INITIAL_MATRIX,&pcis->A_BI);CHKERRQ(ierr);
} else {
Mat newmat;
ierr = MatConvert(matis->A,MATSEQBAIJ,MAT_INITIAL_MATRIX,&newmat);CHKERRQ(ierr);
ierr = MatGetSubMatrix(newmat,pcis->is_I_local,pcis->is_B_local,MAT_INITIAL_MATRIX,&pcis->A_IB);CHKERRQ(ierr);
ierr = MatGetSubMatrix(newmat,pcis->is_B_local,pcis->is_I_local,MAT_INITIAL_MATRIX,&pcis->A_BI);CHKERRQ(ierr);
ierr = MatDestroy(&newmat);CHKERRQ(ierr);
}
/*
Creating work vectors and arrays
*/
ierr = VecDuplicate(matis->x,&pcis->vec1_N);CHKERRQ(ierr);
ierr = VecDuplicate(pcis->vec1_N,&pcis->vec2_N);CHKERRQ(ierr);
ierr = VecCreateSeq(PETSC_COMM_SELF,pcis->n-pcis->n_B,&pcis->vec1_D);CHKERRQ(ierr);
ierr = VecDuplicate(pcis->vec1_D,&pcis->vec2_D);CHKERRQ(ierr);
ierr = VecDuplicate(pcis->vec1_D,&pcis->vec3_D);CHKERRQ(ierr);
ierr = VecDuplicate(pcis->vec1_D,&pcis->vec4_D);CHKERRQ(ierr);
ierr = VecCreateSeq(PETSC_COMM_SELF,pcis->n_B,&pcis->vec1_B);CHKERRQ(ierr);
ierr = VecDuplicate(pcis->vec1_B,&pcis->vec2_B);CHKERRQ(ierr);
ierr = VecDuplicate(pcis->vec1_B,&pcis->vec3_B);CHKERRQ(ierr);
ierr = MatCreateVecs(pc->pmat,&pcis->vec1_global,0);CHKERRQ(ierr);
ierr = PetscMalloc1(pcis->n,&pcis->work_N);CHKERRQ(ierr);
/* Creating the scatter contexts */
ierr = VecScatterCreate(pcis->vec1_global,pcis->is_I_global,pcis->vec1_D,(IS)0,&pcis->global_to_D);CHKERRQ(ierr);
ierr = VecScatterCreate(pcis->vec1_N,pcis->is_B_local,pcis->vec1_B,(IS)0,&pcis->N_to_B);CHKERRQ(ierr);
ierr = VecScatterCreate(pcis->vec1_global,pcis->is_B_global,pcis->vec1_B,(IS)0,&pcis->global_to_B);CHKERRQ(ierr);
/* Creating scaling "matrix" D */
ierr = PetscOptionsGetBool(((PetscObject)pc)->prefix,"-pc_is_use_stiffness_scaling",&pcis->use_stiffness_scaling,NULL);CHKERRQ(ierr);
if (!pcis->D) {
ierr = VecDuplicate(pcis->vec1_B,&pcis->D);CHKERRQ(ierr);
if (!pcis->use_stiffness_scaling) {
ierr = VecSet(pcis->D,pcis->scaling_factor);CHKERRQ(ierr);
} else {
ierr = MatGetDiagonal(matis->A,pcis->vec1_N);CHKERRQ(ierr);
ierr = VecScatterBegin(pcis->N_to_B,pcis->vec1_N,pcis->D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecScatterEnd (pcis->N_to_B,pcis->vec1_N,pcis->D,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
}
}
ierr = VecCopy(pcis->D,pcis->vec1_B);CHKERRQ(ierr);
ierr = MatCreateVecs(pc->pmat,&counter,0);CHKERRQ(ierr); /* temporary auxiliar vector */
ierr = VecSet(counter,0.0);CHKERRQ(ierr);
ierr = VecScatterBegin(pcis->global_to_B,pcis->vec1_B,counter,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
ierr = VecScatterEnd (pcis->global_to_B,pcis->vec1_B,counter,ADD_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
ierr = VecScatterBegin(pcis->global_to_B,counter,pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecScatterEnd (pcis->global_to_B,counter,pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecPointwiseDivide(pcis->D,pcis->D,pcis->vec1_B);CHKERRQ(ierr);
ierr = VecDestroy(&counter);CHKERRQ(ierr);
/* See historical note 01, at the bottom of this file. */
/*
Creating the KSP contexts for the local Dirichlet and Neumann problems.
*/
if (pcis->computesolvers) {
PC pc_ctx;
/* Dirichlet */
ierr = KSPCreate(PETSC_COMM_SELF,&pcis->ksp_D);CHKERRQ(ierr);
ierr = PetscObjectIncrementTabLevel((PetscObject)pcis->ksp_D,(PetscObject)pc,1);CHKERRQ(ierr);
ierr = KSPSetOperators(pcis->ksp_D,pcis->A_II,pcis->A_II);CHKERRQ(ierr);
ierr = KSPSetOptionsPrefix(pcis->ksp_D,"is_localD_");CHKERRQ(ierr);
ierr = KSPGetPC(pcis->ksp_D,&pc_ctx);CHKERRQ(ierr);
ierr = PCSetType(pc_ctx,PCLU);CHKERRQ(ierr);
ierr = KSPSetType(pcis->ksp_D,KSPPREONLY);CHKERRQ(ierr);
ierr = KSPSetFromOptions(pcis->ksp_D);CHKERRQ(ierr);
/* the vectors in the following line are dummy arguments, just telling the KSP the vector size. Values are not used */
ierr = KSPSetUp(pcis->ksp_D);CHKERRQ(ierr);
/* Neumann */
ierr = KSPCreate(PETSC_COMM_SELF,&pcis->ksp_N);CHKERRQ(ierr);
ierr = PetscObjectIncrementTabLevel((PetscObject)pcis->ksp_N,(PetscObject)pc,1);CHKERRQ(ierr);
ierr = KSPSetOperators(pcis->ksp_N,matis->A,matis->A);CHKERRQ(ierr);
ierr = KSPSetOptionsPrefix(pcis->ksp_N,"is_localN_");CHKERRQ(ierr);
ierr = KSPGetPC(pcis->ksp_N,&pc_ctx);CHKERRQ(ierr);
ierr = PCSetType(pc_ctx,PCLU);CHKERRQ(ierr);
ierr = KSPSetType(pcis->ksp_N,KSPPREONLY);CHKERRQ(ierr);
ierr = KSPSetFromOptions(pcis->ksp_N);CHKERRQ(ierr);
{
PetscBool damp_fixed = PETSC_FALSE,
remove_nullspace_fixed = PETSC_FALSE,
set_damping_factor_floating = PETSC_FALSE,
not_damp_floating = PETSC_FALSE,
not_remove_nullspace_floating = PETSC_FALSE;
PetscReal fixed_factor,
floating_factor;
ierr = PetscOptionsGetReal(((PetscObject)pc_ctx)->prefix,"-pc_is_damp_fixed",&fixed_factor,&damp_fixed);CHKERRQ(ierr);
if (!damp_fixed) fixed_factor = 0.0;
ierr = PetscOptionsGetBool(((PetscObject)pc_ctx)->prefix,"-pc_is_damp_fixed",&damp_fixed,NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetBool(((PetscObject)pc_ctx)->prefix,"-pc_is_remove_nullspace_fixed",&remove_nullspace_fixed,NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetReal(((PetscObject)pc_ctx)->prefix,"-pc_is_set_damping_factor_floating",
&floating_factor,&set_damping_factor_floating);CHKERRQ(ierr);
if (!set_damping_factor_floating) floating_factor = 0.0;
ierr = PetscOptionsGetBool(((PetscObject)pc_ctx)->prefix,"-pc_is_set_damping_factor_floating",&set_damping_factor_floating,NULL);CHKERRQ(ierr);
if (!set_damping_factor_floating) floating_factor = 1.e-12;
ierr = PetscOptionsGetBool(((PetscObject)pc_ctx)->prefix,"-pc_is_not_damp_floating",¬_damp_floating,NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetBool(((PetscObject)pc_ctx)->prefix,"-pc_is_not_remove_nullspace_floating",¬_remove_nullspace_floating,NULL);CHKERRQ(ierr);
if (pcis->pure_neumann) { /* floating subdomain */
if (!(not_damp_floating)) {
ierr = PCFactorSetShiftType(pc_ctx,MAT_SHIFT_NONZERO);CHKERRQ(ierr);
ierr = PCFactorSetShiftAmount(pc_ctx,floating_factor);CHKERRQ(ierr);
}
if (!(not_remove_nullspace_floating)) {
MatNullSpace nullsp;
ierr = MatNullSpaceCreate(PETSC_COMM_SELF,PETSC_TRUE,0,NULL,&nullsp);CHKERRQ(ierr);
ierr = KSPSetNullSpace(pcis->ksp_N,nullsp);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nullsp);CHKERRQ(ierr);
}
} else { /* fixed subdomain */
if (damp_fixed) {
ierr = PCFactorSetShiftType(pc_ctx,MAT_SHIFT_NONZERO);CHKERRQ(ierr);
ierr = PCFactorSetShiftAmount(pc_ctx,floating_factor);CHKERRQ(ierr);
}
if (remove_nullspace_fixed) {
MatNullSpace nullsp;
ierr = MatNullSpaceCreate(PETSC_COMM_SELF,PETSC_TRUE,0,NULL,&nullsp);CHKERRQ(ierr);
ierr = KSPSetNullSpace(pcis->ksp_N,nullsp);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nullsp);CHKERRQ(ierr);
}
}
}
/* the vectors in the following line are dummy arguments, just telling the KSP the vector size. Values are not used */
ierr = KSPSetUp(pcis->ksp_N);CHKERRQ(ierr);
}
PetscFunctionReturn(0);
}
PetscErrorCode PCBDDCNullSpaceAssembleCoarse(PC pc, Mat coarse_mat, MatNullSpace* CoarseNullSpace)
{
PC_BDDC *pcbddc = (PC_BDDC*)pc->data;
Mat_IS *matis = (Mat_IS*)pc->pmat->data;
MatNullSpace tempCoarseNullSpace=NULL;
const Vec *nsp_vecs;
Vec *coarse_nsp_vecs,local_vec,local_primal_vec,wcoarse_vec,wcoarse_rhs;
PetscInt nsp_size,coarse_nsp_size,i;
PetscBool nsp_has_cnst;
PetscReal test_null;
PetscErrorCode ierr;
PetscFunctionBegin;
tempCoarseNullSpace = 0;
coarse_nsp_size = 0;
coarse_nsp_vecs = 0;
ierr = MatNullSpaceGetVecs(pcbddc->NullSpace,&nsp_has_cnst,&nsp_size,&nsp_vecs);CHKERRQ(ierr);
if (coarse_mat) {
ierr = PetscMalloc1(nsp_size+1,&coarse_nsp_vecs);CHKERRQ(ierr);
for (i=0;i<nsp_size+1;i++) {
ierr = MatCreateVecs(coarse_mat,&coarse_nsp_vecs[i],NULL);CHKERRQ(ierr);
}
if (pcbddc->dbg_flag) {
ierr = MatCreateVecs(coarse_mat,&wcoarse_vec,&wcoarse_rhs);CHKERRQ(ierr);
}
}
ierr = MatCreateVecs(pcbddc->ConstraintMatrix,&local_vec,&local_primal_vec);CHKERRQ(ierr);
if (nsp_has_cnst) {
ierr = VecSet(local_vec,1.0);CHKERRQ(ierr);
ierr = MatMult(pcbddc->ConstraintMatrix,local_vec,local_primal_vec);CHKERRQ(ierr);
ierr = VecScatterBegin(pcbddc->coarse_loc_to_glob,local_primal_vec,pcbddc->coarse_vec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecScatterEnd(pcbddc->coarse_loc_to_glob,local_primal_vec,pcbddc->coarse_vec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
if (coarse_mat) {
PetscScalar *array_out;
const PetscScalar *array_in;
PetscInt lsize;
if (pcbddc->dbg_flag) {
PetscViewer dbg_viewer = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)coarse_mat));
ierr = MatMult(coarse_mat,wcoarse_vec,wcoarse_rhs);CHKERRQ(ierr);
ierr = VecNorm(wcoarse_rhs,NORM_INFINITY,&test_null);CHKERRQ(ierr);
ierr = PetscViewerASCIIPrintf(dbg_viewer,"Constant coarse null space error % 1.14e\n",test_null);CHKERRQ(ierr);
ierr = PetscViewerFlush(dbg_viewer);CHKERRQ(ierr);
}
ierr = VecGetLocalSize(pcbddc->coarse_vec,&lsize);CHKERRQ(ierr);
ierr = VecGetArrayRead(pcbddc->coarse_vec,&array_in);CHKERRQ(ierr);
ierr = VecGetArray(coarse_nsp_vecs[coarse_nsp_size],&array_out);CHKERRQ(ierr);
ierr = PetscMemcpy(array_out,array_in,lsize*sizeof(PetscScalar));CHKERRQ(ierr);
ierr = VecRestoreArray(coarse_nsp_vecs[coarse_nsp_size],&array_out);CHKERRQ(ierr);
ierr = VecRestoreArrayRead(pcbddc->coarse_vec,&array_in);CHKERRQ(ierr);
coarse_nsp_size++;
}
}
for (i=0;i<nsp_size;i++) {
ierr = VecScatterBegin(matis->rctx,nsp_vecs[i],local_vec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecScatterEnd(matis->rctx,nsp_vecs[i],local_vec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = MatMult(pcbddc->ConstraintMatrix,local_vec,local_primal_vec);CHKERRQ(ierr);
ierr = VecScatterBegin(pcbddc->coarse_loc_to_glob,local_primal_vec,pcbddc->coarse_vec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecScatterEnd(pcbddc->coarse_loc_to_glob,local_primal_vec,pcbddc->coarse_vec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
if (coarse_mat) {
PetscScalar *array_out;
const PetscScalar *array_in;
PetscInt lsize;
if (pcbddc->dbg_flag) {
PetscViewer dbg_viewer = PETSC_VIEWER_STDOUT_(PetscObjectComm((PetscObject)coarse_mat));
ierr = MatMult(coarse_mat,wcoarse_vec,wcoarse_rhs);CHKERRQ(ierr);
ierr = VecNorm(wcoarse_rhs,NORM_2,&test_null);CHKERRQ(ierr);
ierr = PetscViewerASCIIPrintf(dbg_viewer,"Vec %d coarse null space error % 1.14e\n",i,test_null);CHKERRQ(ierr);
ierr = PetscViewerFlush(dbg_viewer);CHKERRQ(ierr);
}
ierr = VecGetLocalSize(pcbddc->coarse_vec,&lsize);CHKERRQ(ierr);
ierr = VecGetArrayRead(pcbddc->coarse_vec,&array_in);CHKERRQ(ierr);
ierr = VecGetArray(coarse_nsp_vecs[coarse_nsp_size],&array_out);CHKERRQ(ierr);
ierr = PetscMemcpy(array_out,array_in,lsize*sizeof(PetscScalar));CHKERRQ(ierr);
ierr = VecRestoreArray(coarse_nsp_vecs[coarse_nsp_size],&array_out);CHKERRQ(ierr);
ierr = VecRestoreArrayRead(pcbddc->coarse_vec,&array_in);CHKERRQ(ierr);
coarse_nsp_size++;
}
}
if (coarse_nsp_size > 0) {
ierr = PCBDDCOrthonormalizeVecs(coarse_nsp_size,coarse_nsp_vecs);CHKERRQ(ierr);
ierr = MatNullSpaceCreate(PetscObjectComm((PetscObject)coarse_mat),PETSC_FALSE,coarse_nsp_size,coarse_nsp_vecs,&tempCoarseNullSpace);CHKERRQ(ierr);
for (i=0;i<nsp_size+1;i++) {
ierr = VecDestroy(&coarse_nsp_vecs[i]);CHKERRQ(ierr);
}
}
if (coarse_mat) {
ierr = PetscFree(coarse_nsp_vecs);CHKERRQ(ierr);
if (pcbddc->dbg_flag) {
ierr = VecDestroy(&wcoarse_vec);CHKERRQ(ierr);
ierr = VecDestroy(&wcoarse_rhs);CHKERRQ(ierr);
}
}
ierr = VecDestroy(&local_vec);CHKERRQ(ierr);
ierr = VecDestroy(&local_primal_vec);CHKERRQ(ierr);
*CoarseNullSpace = tempCoarseNullSpace;
PetscFunctionReturn(0);
}
int main(int argc,char **args)
{
PetscErrorCode ierr;
Mat C;
PetscMPIInt rank,size;
PetscInt i,m = 5,N,start,end,M;
PetscInt idx[4];
PetscScalar Ke[16];
PetscReal h;
Vec u,b;
KSP ksp;
MatNullSpace nullsp;
ierr = PetscInitialize(&argc,&args,(char*)0,help);if (ierr) return ierr;
ierr = PetscOptionsGetInt(NULL,NULL,"-m",&m,NULL);CHKERRQ(ierr);
N = (m+1)*(m+1); /* dimension of matrix */
M = m*m; /* number of elements */
h = 1.0/m; /* mesh width */
ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr);
/* Create stiffness matrix */
ierr = MatCreate(PETSC_COMM_WORLD,&C);CHKERRQ(ierr);
ierr = MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,N,N);CHKERRQ(ierr);
ierr = MatSetFromOptions(C);CHKERRQ(ierr);
ierr = MatSetUp(C);CHKERRQ(ierr);
start = rank*(M/size) + ((M%size) < rank ? (M%size) : rank);
end = start + M/size + ((M%size) > rank);
/* Assemble matrix */
ierr = FormElementStiffness(h*h,Ke);CHKERRQ(ierr); /* element stiffness for Laplacian */
for (i=start; i<end; i++) {
/* location of lower left corner of element */
/* node numbers for the four corners of element */
idx[0] = (m+1)*(i/m) + (i % m);
idx[1] = idx[0]+1; idx[2] = idx[1] + m + 1; idx[3] = idx[2] - 1;
ierr = MatSetValues(C,4,idx,4,idx,Ke,ADD_VALUES);CHKERRQ(ierr);
}
ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
/* Create right-hand-side and solution vectors */
ierr = VecCreate(PETSC_COMM_WORLD,&u);CHKERRQ(ierr);
ierr = VecSetSizes(u,PETSC_DECIDE,N);CHKERRQ(ierr);
ierr = VecSetFromOptions(u);CHKERRQ(ierr);
ierr = PetscObjectSetName((PetscObject)u,"Approx. Solution");CHKERRQ(ierr);
ierr = VecDuplicate(u,&b);CHKERRQ(ierr);
ierr = PetscObjectSetName((PetscObject)b,"Right hand side");CHKERRQ(ierr);
ierr = VecSet(b,1.0);CHKERRQ(ierr);
ierr = VecSetValue(b,0,1.2,ADD_VALUES);CHKERRQ(ierr);
ierr = VecSet(u,0.0);CHKERRQ(ierr);
/* Solve linear system */
ierr = KSPCreate(PETSC_COMM_WORLD,&ksp);CHKERRQ(ierr);
ierr = KSPSetOperators(ksp,C,C);CHKERRQ(ierr);
ierr = KSPSetFromOptions(ksp);CHKERRQ(ierr);
ierr = KSPSetInitialGuessNonzero(ksp,PETSC_TRUE);CHKERRQ(ierr);
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,NULL,&nullsp);CHKERRQ(ierr);
/*
The KSP solver will remove this nullspace from the solution at each iteration
*/
ierr = MatSetNullSpace(C,nullsp);CHKERRQ(ierr);
/*
The KSP solver will remove from the right hand side any portion in this nullspace, thus making the linear system consistent.
*/
ierr = MatSetTransposeNullSpace(C,nullsp);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nullsp);CHKERRQ(ierr);
ierr = KSPSolve(ksp,b,u);CHKERRQ(ierr);
/* Free work space */
ierr = KSPDestroy(&ksp);CHKERRQ(ierr);
ierr = VecDestroy(&u);CHKERRQ(ierr);
ierr = VecDestroy(&b);CHKERRQ(ierr);
ierr = MatDestroy(&C);CHKERRQ(ierr);
ierr = PetscFinalize();
return ierr;
}
int main(int argc,char **argv)
{
SNES snes; /* SNES context */
Mat J; /* Jacobian matrix */
DM da;
Vec x,r; /* vectors */
PetscErrorCode ierr;
PetscInt N = 5;
MatNullSpace constants;
ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
ierr = PetscOptionsGetInt(NULL,NULL,"-n",&N,NULL);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Create nonlinear solver context
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = SNESCreate(PETSC_COMM_WORLD,&snes);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Create vector data structures; set function evaluation routine
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
/*
Create distributed array (DMDA) to manage parallel grid and vectors
*/
ierr = DMDACreate1d(PETSC_COMM_WORLD,DM_BOUNDARY_PERIODIC,N,1,1,NULL,&da);CHKERRQ(ierr);
ierr = DMSetFromOptions(da);CHKERRQ(ierr);
ierr = DMSetUp(da);CHKERRQ(ierr);
/*
Extract global and local vectors from DMDA; then duplicate for remaining
vectors that are the same types
*/
ierr = DMCreateGlobalVector(da,&x);CHKERRQ(ierr);
ierr = VecDuplicate(x,&r);CHKERRQ(ierr);
/*
Set function evaluation routine and vector. Whenever the nonlinear
solver needs to compute the nonlinear function, it will call this
routine.
- Note that the final routine argument is the user-defined
context that provides application-specific data for the
function evaluation routine.
*/
ierr = SNESSetFunction(snes,r,FormFunction,da);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Create matrix data structure; set Jacobian evaluation routine
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = DMCreateMatrix(da,&J);CHKERRQ(ierr);
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,NULL,&constants);CHKERRQ(ierr);
ierr = MatSetNullSpace(J,constants);CHKERRQ(ierr);
ierr = SNESSetJacobian(snes,J,J,FormJacobian,da);CHKERRQ(ierr);
ierr = SNESSetFromOptions(snes);CHKERRQ(ierr);
ierr = SNESSolve(snes,NULL,x);CHKERRQ(ierr);
ierr = VecDestroy(&x);CHKERRQ(ierr);
ierr = VecDestroy(&r);CHKERRQ(ierr);
ierr = MatDestroy(&J);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&constants);CHKERRQ(ierr);
ierr = SNESDestroy(&snes);CHKERRQ(ierr);
ierr = DMDestroy(&da);CHKERRQ(ierr);
ierr = PetscFinalize();
return ierr;
}
/*@
MatNullSpaceCreateRigidBody - create rigid body modes from coordinates
Collective on Vec
Input Argument:
. coords - block of coordinates of each node, must have block size set
Output Argument:
. sp - the null space
Level: advanced
Notes:
If you are solving an elasticity problems you should likely use this, in conjunction with ee MatSetNearNullspace(), to provide information that
the PCGAMG preconditioner can use to construct a much more efficient preconditioner.
If you are solving an elasticity problem with pure Neumann boundary conditions you can use this in conjunction with MatSetNullspace() to
provide this information to the linear solver so it can handle the null space appropriately in the linear solution.
.seealso: MatNullSpaceCreate(), MatSetNearNullspace(), MatSetNullspace()
@*/
PetscErrorCode MatNullSpaceCreateRigidBody(Vec coords,MatNullSpace *sp)
{
PetscErrorCode ierr;
const PetscScalar *x;
PetscScalar *v[6],dots[5];
Vec vec[6];
PetscInt n,N,dim,nmodes,i,j;
PetscReal sN;
PetscFunctionBegin;
ierr = VecGetBlockSize(coords,&dim);CHKERRQ(ierr);
ierr = VecGetLocalSize(coords,&n);CHKERRQ(ierr);
ierr = VecGetSize(coords,&N);CHKERRQ(ierr);
n /= dim;
N /= dim;
sN = 1./PetscSqrtReal((PetscReal)N);
switch (dim) {
case 1:
ierr = MatNullSpaceCreate(PetscObjectComm((PetscObject)coords),PETSC_TRUE,0,NULL,sp);CHKERRQ(ierr);
break;
case 2:
case 3:
nmodes = (dim == 2) ? 3 : 6;
ierr = VecCreate(PetscObjectComm((PetscObject)coords),&vec[0]);CHKERRQ(ierr);
ierr = VecSetSizes(vec[0],dim*n,dim*N);CHKERRQ(ierr);
ierr = VecSetBlockSize(vec[0],dim);CHKERRQ(ierr);
ierr = VecSetUp(vec[0]);CHKERRQ(ierr);
for (i=1; i<nmodes; i++) {ierr = VecDuplicate(vec[0],&vec[i]);CHKERRQ(ierr);}
for (i=0; i<nmodes; i++) {ierr = VecGetArray(vec[i],&v[i]);CHKERRQ(ierr);}
ierr = VecGetArrayRead(coords,&x);CHKERRQ(ierr);
for (i=0; i<n; i++) {
if (dim == 2) {
v[0][i*2+0] = sN;
v[0][i*2+1] = 0.;
v[1][i*2+0] = 0.;
v[1][i*2+1] = sN;
/* Rotations */
v[2][i*2+0] = -x[i*2+1];
v[2][i*2+1] = x[i*2+0];
} else {
v[0][i*3+0] = sN;
v[0][i*3+1] = 0.;
v[0][i*3+2] = 0.;
v[1][i*3+0] = 0.;
v[1][i*3+1] = sN;
v[1][i*3+2] = 0.;
v[2][i*3+0] = 0.;
v[2][i*3+1] = 0.;
v[2][i*3+2] = sN;
v[3][i*3+0] = x[i*3+1];
v[3][i*3+1] = -x[i*3+0];
v[3][i*3+2] = 0.;
v[4][i*3+0] = 0.;
v[4][i*3+1] = -x[i*3+2];
v[4][i*3+2] = x[i*3+1];
v[5][i*3+0] = x[i*3+2];
v[5][i*3+1] = 0.;
v[5][i*3+2] = -x[i*3+0];
}
}
for (i=0; i<nmodes; i++) {ierr = VecRestoreArray(vec[i],&v[i]);CHKERRQ(ierr);}
ierr = VecRestoreArrayRead(coords,&x);CHKERRQ(ierr);
for (i=dim; i<nmodes; i++) {
/* Orthonormalize vec[i] against vec[0:i-1] */
ierr = VecMDot(vec[i],i,vec,dots);CHKERRQ(ierr);
for (j=0; j<i; j++) dots[j] *= -1.;
ierr = VecMAXPY(vec[i],i,dots,vec);CHKERRQ(ierr);
ierr = VecNormalize(vec[i],NULL);CHKERRQ(ierr);
}
ierr = MatNullSpaceCreate(PetscObjectComm((PetscObject)coords),PETSC_FALSE,nmodes,vec,sp);CHKERRQ(ierr);
for (i=0; i<nmodes; i++) {ierr = VecDestroy(&vec[i]);CHKERRQ(ierr);}
}
PetscFunctionReturn(0);
}
PetscErrorCode PCBDDCNullSpaceAdaptGlobal(PC pc)
{
PC_IS* pcis = (PC_IS*) (pc->data);
PC_BDDC* pcbddc = (PC_BDDC*)(pc->data);
KSP inv_change;
PC pc_change;
const Vec *nsp_vecs;
Vec *new_nsp_vecs;
PetscInt i,nsp_size,new_nsp_size,start_new;
PetscBool nsp_has_cnst;
MatNullSpace new_nsp;
PetscErrorCode ierr;
MPI_Comm comm;
PetscFunctionBegin;
/* create KSP for change of basis */
ierr = KSPCreate(PETSC_COMM_SELF,&inv_change);CHKERRQ(ierr);
ierr = KSPSetOperators(inv_change,pcbddc->ChangeOfBasisMatrix,pcbddc->ChangeOfBasisMatrix,SAME_PRECONDITIONER);CHKERRQ(ierr);
ierr = KSPSetType(inv_change,KSPPREONLY);CHKERRQ(ierr);
ierr = KSPGetPC(inv_change,&pc_change);CHKERRQ(ierr);
ierr = PCSetType(pc_change,PCLU);CHKERRQ(ierr);
ierr = KSPSetUp(inv_change);CHKERRQ(ierr);
/* get nullspace and transform it */
ierr = MatNullSpaceGetVecs(pcbddc->NullSpace,&nsp_has_cnst,&nsp_size,&nsp_vecs);CHKERRQ(ierr);
new_nsp_size = nsp_size;
if (nsp_has_cnst) {
new_nsp_size++;
}
ierr = PetscMalloc(new_nsp_size*sizeof(Vec),&new_nsp_vecs);CHKERRQ(ierr);
for (i=0;i<new_nsp_size;i++) {
ierr = VecDuplicate(pcis->vec1_global,&new_nsp_vecs[i]);CHKERRQ(ierr);
}
start_new = 0;
if (nsp_has_cnst) {
start_new = 1;
ierr = VecSet(new_nsp_vecs[0],1.0);CHKERRQ(ierr);
ierr = VecSet(pcis->vec1_B,1.0);CHKERRQ(ierr);
ierr = KSPSolve(inv_change,pcis->vec1_B,pcis->vec1_B);
ierr = VecScatterBegin(pcis->global_to_B,pcis->vec1_B,new_nsp_vecs[0],INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
ierr = VecScatterEnd (pcis->global_to_B,pcis->vec1_B,new_nsp_vecs[0],INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
}
for (i=0;i<nsp_size;i++) {
ierr = VecCopy(nsp_vecs[i],new_nsp_vecs[i+start_new]);CHKERRQ(ierr);
ierr = VecScatterBegin(pcis->global_to_B,nsp_vecs[i],pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecScatterEnd (pcis->global_to_B,nsp_vecs[i],pcis->vec1_B,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = KSPSolve(inv_change,pcis->vec1_B,pcis->vec1_B);
ierr = VecScatterBegin(pcis->global_to_B,pcis->vec1_B,new_nsp_vecs[i+start_new],INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
ierr = VecScatterEnd (pcis->global_to_B,pcis->vec1_B,new_nsp_vecs[i+start_new],INSERT_VALUES,SCATTER_REVERSE);CHKERRQ(ierr);
}
ierr = PCBDDCOrthonormalizeVecs(new_nsp_size,new_nsp_vecs);CHKERRQ(ierr);
#if 0
PetscBool nsp_t=PETSC_FALSE;
ierr = MatNullSpaceTest(pcbddc->NullSpace,pc->pmat,&nsp_t);CHKERRQ(ierr);
printf("Original Null Space test: %d\n",nsp_t);
Mat temp_mat;
Mat_IS* matis = (Mat_IS*)pc->pmat->data;
temp_mat = matis->A;
matis->A = pcbddc->local_mat;
pcbddc->local_mat = temp_mat;
ierr = MatNullSpaceTest(pcbddc->NullSpace,pc->pmat,&nsp_t);CHKERRQ(ierr);
printf("Original Null Space, mat changed test: %d\n",nsp_t);
{
PetscReal test_norm;
for (i=0;i<new_nsp_size;i++) {
ierr = MatMult(pc->pmat,new_nsp_vecs[i],pcis->vec1_global);CHKERRQ(ierr);
ierr = VecNorm(pcis->vec1_global,NORM_2,&test_norm);CHKERRQ(ierr);
if (test_norm > 1.e-12) {
printf("------------ERROR VEC %d------------------\n",i);
ierr = VecView(pcis->vec1_global,PETSC_VIEWER_STDOUT_WORLD);
printf("------------------------------------------\n");
}
}
}
#endif
ierr = KSPDestroy(&inv_change);CHKERRQ(ierr);
ierr = PetscObjectGetComm((PetscObject)pc,&comm);CHKERRQ(ierr);
ierr = MatNullSpaceCreate(comm,PETSC_FALSE,new_nsp_size,new_nsp_vecs,&new_nsp);CHKERRQ(ierr);
ierr = PCBDDCSetNullSpace(pc,new_nsp);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&new_nsp);CHKERRQ(ierr);
#if 0
ierr = MatNullSpaceTest(pcbddc->NullSpace,pc->pmat,&nsp_t);CHKERRQ(ierr);
printf("New Null Space, mat changed: %d\n",nsp_t);
temp_mat = matis->A;
matis->A = pcbddc->local_mat;
pcbddc->local_mat = temp_mat;
ierr = MatNullSpaceTest(pcbddc->NullSpace,pc->pmat,&nsp_t);CHKERRQ(ierr);
printf("New Null Space, mat original: %d\n",nsp_t);
#endif
for (i=0;i<new_nsp_size;i++) {
ierr = VecDestroy(&new_nsp_vecs[i]);CHKERRQ(ierr);
}
ierr = PetscFree(new_nsp_vecs);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
PetscErrorCode ComputeMatrix(DM da, Mat J, Mat jac)
{
PetscErrorCode ierr;
PetscInt i, j, mx, my, xm, ym, xs, ys, num, numi, numj;
PetscScalar v[5], Hx, Hy, HydHx, HxdHy;
MatStencil row, col[5];
PetscFunctionBeginUser;
ierr = DMDAGetInfo(da, 0, &mx, &my, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0);
CHKERRQ(ierr);
Hx = 1.0 / (PetscReal)(mx);
Hy = 1.0 / (PetscReal)(my);
HxdHy = Hx / Hy;
HydHx = Hy / Hx;
ierr = DMDAGetCorners(da, &xs, &ys, 0, &xm, &ym, 0);
CHKERRQ(ierr);
for (j = ys; j < ys + ym; j++) {
for (i = xs; i < xs + xm; i++) {
row.i = i;
row.j = j;
if (i == 0 || j == 0 || i == mx - 1 || j == my - 1) {
num = 0;
numi = 0;
numj = 0;
if (j != 0) {
v[num] = -HxdHy;
col[num].i = i;
col[num].j = j - 1;
num++;
numj++;
}
if (i != 0) {
v[num] = -HydHx;
col[num].i = i - 1;
col[num].j = j;
num++;
numi++;
}
if (i != mx - 1) {
v[num] = -HydHx;
col[num].i = i + 1;
col[num].j = j;
num++;
numi++;
}
if (j != my - 1) {
v[num] = -HxdHy;
col[num].i = i;
col[num].j = j + 1;
num++;
numj++;
}
v[num] = (PetscReal)(numj)*HxdHy + (PetscReal)(numi)*HydHx;
col[num].i = i;
col[num].j = j;
num++;
ierr = MatSetValuesStencil(jac, 1, &row, num, col, v, INSERT_VALUES);
CHKERRQ(ierr);
}
else {
v[0] = -HxdHy;
col[0].i = i;
col[0].j = j - 1;
v[1] = -HydHx;
col[1].i = i - 1;
col[1].j = j;
v[2] = 2.0 * (HxdHy + HydHx);
col[2].i = i;
col[2].j = j;
v[3] = -HydHx;
col[3].i = i + 1;
col[3].j = j;
v[4] = -HxdHy;
col[4].i = i;
col[4].j = j + 1;
ierr = MatSetValuesStencil(jac, 1, &row, 5, col, v, INSERT_VALUES);
CHKERRQ(ierr);
}
}
}
ierr = MatAssemblyBegin(jac, MAT_FINAL_ASSEMBLY);
CHKERRQ(ierr);
ierr = MatAssemblyEnd(jac, MAT_FINAL_ASSEMBLY);
CHKERRQ(ierr);
MatNullSpace nullspace;
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD, PETSC_TRUE, 0, 0, &nullspace);
CHKERRQ(ierr);
ierr = MatSetNullSpace(J, nullspace);
CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nullspace);
CHKERRQ(ierr);
PetscFunctionReturn(0);
}
PetscErrorCode PCBDDCNullSpaceAssembleCoarse(PC pc, MatNullSpace* CoarseNullSpace)
{
PC_BDDC *pcbddc = (PC_BDDC*)pc->data;
Mat_IS *matis = (Mat_IS*)pc->pmat->data;
MatNullSpace tempCoarseNullSpace;
const Vec *nsp_vecs;
Vec *coarse_nsp_vecs,local_vec,local_primal_vec;
PetscInt nsp_size,coarse_nsp_size,i;
PetscBool nsp_has_cnst;
PetscReal test_null;
PetscErrorCode ierr;
PetscFunctionBegin;
tempCoarseNullSpace = 0;
coarse_nsp_size = 0;
coarse_nsp_vecs = 0;
ierr = MatNullSpaceGetVecs(pcbddc->NullSpace,&nsp_has_cnst,&nsp_size,&nsp_vecs);CHKERRQ(ierr);
if (pcbddc->coarse_mat) {
ierr = PetscMalloc((nsp_size+1)*sizeof(Vec),&coarse_nsp_vecs);CHKERRQ(ierr);
for (i=0;i<nsp_size+1;i++) {
ierr = VecDuplicate(pcbddc->coarse_vec,&coarse_nsp_vecs[i]);CHKERRQ(ierr);
}
}
ierr = MatGetVecs(pcbddc->ConstraintMatrix,&local_vec,&local_primal_vec);CHKERRQ(ierr);
if (nsp_has_cnst) {
ierr = VecSet(local_vec,1.0);CHKERRQ(ierr);
ierr = MatMult(pcbddc->ConstraintMatrix,local_vec,local_primal_vec);CHKERRQ(ierr);
ierr = PCBDDCScatterCoarseDataBegin(pc,local_primal_vec,pcbddc->coarse_vec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = PCBDDCScatterCoarseDataEnd(pc,local_primal_vec,pcbddc->coarse_vec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
if (pcbddc->coarse_mat) {
if (pcbddc->dbg_flag) {
ierr = MatMult(pcbddc->coarse_mat,pcbddc->coarse_vec,pcbddc->coarse_rhs);CHKERRQ(ierr);
ierr = VecNorm(pcbddc->coarse_rhs,NORM_INFINITY,&test_null);CHKERRQ(ierr);
ierr = PetscViewerASCIIPrintf(pcbddc->dbg_viewer,"Constant coarse null space error % 1.14e\n",test_null);CHKERRQ(ierr);
}
ierr = VecCopy(pcbddc->coarse_vec,coarse_nsp_vecs[coarse_nsp_size]);CHKERRQ(ierr);
coarse_nsp_size++;
}
}
for (i=0;i<nsp_size;i++) {
ierr = VecScatterBegin(matis->ctx,nsp_vecs[i],local_vec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = VecScatterEnd(matis->ctx,nsp_vecs[i],local_vec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = MatMult(pcbddc->ConstraintMatrix,local_vec,local_primal_vec);CHKERRQ(ierr);
ierr = PCBDDCScatterCoarseDataBegin(pc,local_primal_vec,pcbddc->coarse_vec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
ierr = PCBDDCScatterCoarseDataEnd(pc,local_primal_vec,pcbddc->coarse_vec,INSERT_VALUES,SCATTER_FORWARD);CHKERRQ(ierr);
if (pcbddc->coarse_mat) {
if (pcbddc->dbg_flag) {
ierr = MatMult(pcbddc->coarse_mat,pcbddc->coarse_vec,pcbddc->coarse_rhs);CHKERRQ(ierr);
ierr = VecNorm(pcbddc->coarse_rhs,NORM_2,&test_null);CHKERRQ(ierr);
ierr = PetscViewerASCIIPrintf(pcbddc->dbg_viewer,"Vec %d coarse null space error % 1.14e\n",i,test_null);CHKERRQ(ierr);
}
ierr = VecCopy(pcbddc->coarse_vec,coarse_nsp_vecs[coarse_nsp_size]);CHKERRQ(ierr);
coarse_nsp_size++;
}
}
if (coarse_nsp_size > 0) {
ierr = PCBDDCOrthonormalizeVecs(coarse_nsp_size,coarse_nsp_vecs);CHKERRQ(ierr);
ierr = MatNullSpaceCreate(PetscObjectComm((PetscObject)(pcbddc->coarse_mat)),PETSC_FALSE,coarse_nsp_size,coarse_nsp_vecs,&tempCoarseNullSpace);CHKERRQ(ierr);
for (i=0;i<nsp_size+1;i++) {
ierr = VecDestroy(&coarse_nsp_vecs[i]);CHKERRQ(ierr);
}
}
ierr = PetscFree(coarse_nsp_vecs);CHKERRQ(ierr);
ierr = VecDestroy(&local_vec);CHKERRQ(ierr);
ierr = VecDestroy(&local_primal_vec);CHKERRQ(ierr);
*CoarseNullSpace = tempCoarseNullSpace;
PetscFunctionReturn(0);
}
int main(int argc,char **args)
{
Mat C;
int i,m = 5,rank,size,N,start,end,M;
int ierr,idx[4];
PetscBool flg;
PetscScalar Ke[16];
PetscReal h;
Vec u,b;
KSP ksp;
MatNullSpace nullsp;
PetscInitialize(&argc,&args,(char*)0,help);
ierr = PetscOptionsGetInt(NULL,"-m",&m,NULL);CHKERRQ(ierr);
N = (m+1)*(m+1); /* dimension of matrix */
M = m*m; /* number of elements */
h = 1.0/m; /* mesh width */
ierr = MPI_Comm_rank(PETSC_COMM_WORLD,&rank);CHKERRQ(ierr);
ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr);
/* Create stiffness matrix */
ierr = MatCreate(PETSC_COMM_WORLD,&C);CHKERRQ(ierr);
ierr = MatSetSizes(C,PETSC_DECIDE,PETSC_DECIDE,N,N);CHKERRQ(ierr);
ierr = MatSetFromOptions(C);CHKERRQ(ierr);
start = rank*(M/size) + ((M%size) < rank ? (M%size) : rank);
end = start + M/size + ((M%size) > rank);
/* Assemble matrix */
ierr = FormElementStiffness(h*h,Ke); /* element stiffness for Laplacian */
for (i=start; i<end; i++) {
/* location of lower left corner of element */
/* node numbers for the four corners of element */
idx[0] = (m+1)*(i/m) + (i % m);
idx[1] = idx[0]+1; idx[2] = idx[1] + m + 1; idx[3] = idx[2] - 1;
ierr = MatSetValues(C,4,idx,4,idx,Ke,ADD_VALUES);CHKERRQ(ierr);
}
ierr = MatAssemblyBegin(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
ierr = MatAssemblyEnd(C,MAT_FINAL_ASSEMBLY);CHKERRQ(ierr);
/* Create right-hand-side and solution vectors */
ierr = VecCreate(PETSC_COMM_WORLD,&u);CHKERRQ(ierr);
ierr = VecSetSizes(u,PETSC_DECIDE,N);CHKERRQ(ierr);
ierr = VecSetFromOptions(u);CHKERRQ(ierr);
ierr = PetscObjectSetName((PetscObject)u,"Approx. Solution");CHKERRQ(ierr);
ierr = VecDuplicate(u,&b);CHKERRQ(ierr);
ierr = PetscObjectSetName((PetscObject)b,"Right hand side");CHKERRQ(ierr);
ierr = VecSet(u,1.0);CHKERRQ(ierr);
ierr = MatMult(C,u,b);CHKERRQ(ierr);
ierr = VecSet(u,0.0);CHKERRQ(ierr);
/* Solve linear system */
ierr = KSPCreate(PETSC_COMM_WORLD,&ksp);CHKERRQ(ierr);
ierr = KSPSetOperators(ksp,C,C,DIFFERENT_NONZERO_PATTERN);CHKERRQ(ierr);
ierr = KSPSetFromOptions(ksp);CHKERRQ(ierr);
ierr = KSPSetInitialGuessNonzero(ksp,PETSC_TRUE);CHKERRQ(ierr);
flg = PETSC_FALSE;
ierr = PetscOptionsGetBool(NULL,"-fixnullspace",&flg,NULL);CHKERRQ(ierr);
if (flg) {
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,NULL,&nullsp);CHKERRQ(ierr);
ierr = KSPSetNullSpace(ksp,nullsp);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&&nullsp);CHKERRQ(ierr);
}
ierr = KSPSolve(ksp,b,u);CHKERRQ(ierr);
/* Free work space */
ierr = KSPDestroy(&ksp);CHKERRQ(ierr);
ierr = VecDestroy(&u);CHKERRQ(ierr);
ierr = VecDestroy(&b);CHKERRQ(ierr);
ierr = MatDestroy(&C);CHKERRQ(ierr);
ierr = PetscFinalize();
return 0;
}
void
PetscNonlinearSolver<T>::build_mat_null_space(NonlinearImplicitSystem::ComputeVectorSubspace* computeSubspaceObject,
void (*computeSubspace)(std::vector<NumericVector<Number>*>&, sys_type&),
MatNullSpace *msp)
{
PetscErrorCode ierr;
std::vector<NumericVector<Number>* > sp;
if (computeSubspaceObject)
(*computeSubspaceObject)(sp, this->system());
else
(*computeSubspace)(sp, this->system());
*msp = PETSC_NULL;
if (sp.size())
{
Vec *modes;
PetscScalar *dots;
PetscInt nmodes = sp.size();
ierr = PetscMalloc2(nmodes,Vec,&modes,nmodes,PetscScalar,&dots);
LIBMESH_CHKERRABORT(ierr);
for (PetscInt i=0; i<nmodes; ++i)
{
PetscVector<T>* pv = libmesh_cast_ptr<PetscVector<T>*>(sp[i]);
Vec v = pv->vec();
ierr = VecDuplicate(v, modes+i);
LIBMESH_CHKERRABORT(ierr);
ierr = VecCopy(v,modes[i]);
LIBMESH_CHKERRABORT(ierr);
}
// Normalize.
ierr = VecNormalize(modes[0],PETSC_NULL);
LIBMESH_CHKERRABORT(ierr);
for (PetscInt i=1; i<nmodes; i++)
{
// Orthonormalize vec[i] against vec[0:i-1]
ierr = VecMDot(modes[i],i,modes,dots);
LIBMESH_CHKERRABORT(ierr);
for (PetscInt j=0; j<i; j++)
dots[j] *= -1.;
ierr = VecMAXPY(modes[i],i,dots,modes);
LIBMESH_CHKERRABORT(ierr);
ierr = VecNormalize(modes[i],PETSC_NULL);
LIBMESH_CHKERRABORT(ierr);
}
ierr = MatNullSpaceCreate(this->comm().get(), PETSC_FALSE, nmodes, modes, msp);
LIBMESH_CHKERRABORT(ierr);
for (PetscInt i=0; i<nmodes; ++i)
{
ierr = VecDestroy(modes+i);
LIBMESH_CHKERRABORT(ierr);
}
ierr = PetscFree2(modes,dots);
LIBMESH_CHKERRABORT(ierr);
}
}
PetscErrorCode PCBDDCNullSpaceAdaptGlobal(PC pc)
{
PC_IS* pcis = (PC_IS*)(pc->data);
PC_BDDC* pcbddc = (PC_BDDC*)(pc->data);
KSP inv_change;
const Vec *nsp_vecs;
Vec *new_nsp_vecs;
PetscInt i,nsp_size,new_nsp_size,start_new;
PetscBool nsp_has_cnst;
MatNullSpace new_nsp;
PetscErrorCode ierr;
PetscFunctionBegin;
/* create KSP for change of basis */
ierr = MatGetSize(pcbddc->ChangeOfBasisMatrix,&i,NULL);CHKERRQ(ierr);
ierr = KSPCreate(PetscObjectComm((PetscObject)pc),&inv_change);CHKERRQ(ierr);
ierr = KSPSetErrorIfNotConverged(inv_change,pc->erroriffailure);CHKERRQ(ierr);
ierr = KSPSetOperators(inv_change,pcbddc->ChangeOfBasisMatrix,pcbddc->ChangeOfBasisMatrix);CHKERRQ(ierr);
ierr = KSPSetTolerances(inv_change,1.e-8,1.e-8,PETSC_DEFAULT,2*i);CHKERRQ(ierr);
if (pcbddc->dbg_flag) {
ierr = KSPMonitorSet(inv_change,KSPMonitorDefault,pcbddc->dbg_viewer,NULL);CHKERRQ(ierr);
}
ierr = KSPSetUp(inv_change);CHKERRQ(ierr);
/* get nullspace and transform it */
ierr = MatNullSpaceGetVecs(pcbddc->NullSpace,&nsp_has_cnst,&nsp_size,&nsp_vecs);CHKERRQ(ierr);
new_nsp_size = nsp_size;
if (nsp_has_cnst) {
new_nsp_size++;
}
ierr = VecDuplicateVecs(pcis->vec1_global,new_nsp_size,&new_nsp_vecs);CHKERRQ(ierr);
start_new = 0;
if (nsp_has_cnst) {
start_new = 1;
ierr = VecSet(new_nsp_vecs[0],1.0);CHKERRQ(ierr);
if (pcbddc->dbg_flag) {
ierr = PetscViewerFlush(pcbddc->dbg_viewer);CHKERRQ(ierr);
ierr = PetscViewerASCIIPrintf(pcbddc->dbg_viewer,"Mapping constant in nullspace\n");CHKERRQ(ierr);
}
ierr = KSPSolve(inv_change,new_nsp_vecs[0],new_nsp_vecs[0]);CHKERRQ(ierr);
}
for (i=0;i<nsp_size;i++) {
ierr = PetscViewerFlush(pcbddc->dbg_viewer);CHKERRQ(ierr);
ierr = PetscViewerASCIIPrintf(pcbddc->dbg_viewer,"Mapping %dth vector in nullspace\n",i);CHKERRQ(ierr);
ierr = KSPSolve(inv_change,nsp_vecs[i],new_nsp_vecs[i+start_new]);CHKERRQ(ierr);
}
ierr = PCBDDCOrthonormalizeVecs(new_nsp_size,new_nsp_vecs);CHKERRQ(ierr);
ierr = MatNullSpaceCreate(PetscObjectComm((PetscObject)pc),PETSC_FALSE,new_nsp_size,new_nsp_vecs,&new_nsp);CHKERRQ(ierr);
ierr = PCBDDCSetNullSpace(pc,new_nsp);CHKERRQ(ierr);
/* free */
ierr = KSPDestroy(&inv_change);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&new_nsp);CHKERRQ(ierr);
ierr = VecDestroyVecs(new_nsp_size,&new_nsp_vecs);CHKERRQ(ierr);
/* check */
if (pcbddc->dbg_flag) {
PetscBool nsp_t=PETSC_FALSE;
Mat temp_mat;
Mat_IS* matis = (Mat_IS*)pc->pmat->data;
temp_mat = matis->A;
matis->A = pcbddc->local_mat;
pcbddc->local_mat = temp_mat;
ierr = MatNullSpaceTest(pcbddc->NullSpace,pc->pmat,&nsp_t);CHKERRQ(ierr);
ierr = PetscPrintf(PetscObjectComm((PetscObject)(pc->pmat)),"Check nullspace with change of basis: %d\n",nsp_t);CHKERRQ(ierr);
temp_mat = matis->A;
matis->A = pcbddc->local_mat;
pcbddc->local_mat = temp_mat;
}
PetscFunctionReturn(0);
}
int main(int argc,char **argv)
{
AppCtx appctx; /* user-defined application context */
PetscErrorCode ierr;
PetscInt i, xs, xm, ind, j, lenglob;
PetscReal x, *wrk_ptr1, *wrk_ptr2;
MatNullSpace nsp;
PetscMPIInt size;
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Initialize program and set problem parameters
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
PetscFunctionBegin;
ierr = PetscInitialize(&argc,&argv,(char*)0,help);if (ierr) return ierr;
/*initialize parameters */
appctx.param.N = 10; /* order of the spectral element */
appctx.param.E = 10; /* number of elements */
appctx.param.L = 4.0; /* length of the domain */
appctx.param.mu = 0.01; /* diffusion coefficient */
appctx.initial_dt = 5e-3;
appctx.param.steps = PETSC_MAX_INT;
appctx.param.Tend = 4;
ierr = PetscOptionsGetInt(NULL,NULL,"-N",&appctx.param.N,NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetInt(NULL,NULL,"-E",&appctx.param.E,NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetReal(NULL,NULL,"-Tend",&appctx.param.Tend,NULL);CHKERRQ(ierr);
ierr = PetscOptionsGetReal(NULL,NULL,"-mu",&appctx.param.mu,NULL);CHKERRQ(ierr);
appctx.param.Le = appctx.param.L/appctx.param.E;
ierr = MPI_Comm_size(PETSC_COMM_WORLD,&size);CHKERRQ(ierr);
if (appctx.param.E % size) SETERRQ(PETSC_COMM_WORLD,PETSC_ERR_ARG_WRONG,"Number of elements must be divisible by number of processes");
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Create GLL data structures
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = PetscGLLCreate(appctx.param.N,PETSCGLL_VIA_LINEARALGEBRA,&appctx.SEMop.gll);CHKERRQ(ierr);
lenglob = appctx.param.E*(appctx.param.N-1);
/*
Create distributed array (DMDA) to manage parallel grid and vectors
and to set up the ghost point communication pattern. There are E*(Nl-1)+1
total grid values spread equally among all the processors, except first and last
*/
ierr = DMDACreate1d(PETSC_COMM_WORLD,DM_BOUNDARY_PERIODIC,lenglob,1,1,NULL,&appctx.da);CHKERRQ(ierr);
ierr = DMSetFromOptions(appctx.da);CHKERRQ(ierr);
ierr = DMSetUp(appctx.da);CHKERRQ(ierr);
/*
Extract global and local vectors from DMDA; we use these to store the
approximate solution. Then duplicate these for remaining vectors that
have the same types.
*/
ierr = DMCreateGlobalVector(appctx.da,&appctx.dat.curr_sol);CHKERRQ(ierr);
ierr = VecDuplicate(appctx.dat.curr_sol,&appctx.SEMop.grid);CHKERRQ(ierr);
ierr = VecDuplicate(appctx.dat.curr_sol,&appctx.SEMop.mass);CHKERRQ(ierr);
ierr = DMDAGetCorners(appctx.da,&xs,NULL,NULL,&xm,NULL,NULL);CHKERRQ(ierr);
ierr = DMDAVecGetArray(appctx.da,appctx.SEMop.grid,&wrk_ptr1);CHKERRQ(ierr);
ierr = DMDAVecGetArray(appctx.da,appctx.SEMop.mass,&wrk_ptr2);CHKERRQ(ierr);
/* Compute function over the locally owned part of the grid */
xs=xs/(appctx.param.N-1);
xm=xm/(appctx.param.N-1);
/*
Build total grid and mass over entire mesh (multi-elemental)
*/
for (i=xs; i<xs+xm; i++) {
for (j=0; j<appctx.param.N-1; j++) {
x = (appctx.param.Le/2.0)*(appctx.SEMop.gll.nodes[j]+1.0)+appctx.param.Le*i;
ind=i*(appctx.param.N-1)+j;
wrk_ptr1[ind]=x;
wrk_ptr2[ind]=.5*appctx.param.Le*appctx.SEMop.gll.weights[j];
if (j==0) wrk_ptr2[ind]+=.5*appctx.param.Le*appctx.SEMop.gll.weights[j];
}
}
ierr = DMDAVecRestoreArray(appctx.da,appctx.SEMop.grid,&wrk_ptr1);CHKERRQ(ierr);
ierr = DMDAVecRestoreArray(appctx.da,appctx.SEMop.mass,&wrk_ptr2);CHKERRQ(ierr);
/* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -
Create matrix data structure; set matrix evaluation routine.
- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
ierr = DMSetMatrixPreallocateOnly(appctx.da, PETSC_TRUE);CHKERRQ(ierr);
ierr = DMCreateMatrix(appctx.da,&appctx.SEMop.stiff);CHKERRQ(ierr);
ierr = DMCreateMatrix(appctx.da,&appctx.SEMop.grad);CHKERRQ(ierr);
/*
For linear problems with a time-dependent f(u,t) in the equation
u_t = f(u,t), the user provides the discretized right-hand-side
as a time-dependent matrix.
*/
ierr = RHSMatrixLaplaciangllDM(appctx.ts,0.0,appctx.dat.curr_sol,appctx.SEMop.stiff,appctx.SEMop.stiff,&appctx);CHKERRQ(ierr);
ierr = RHSMatrixAdvectiongllDM(appctx.ts,0.0,appctx.dat.curr_sol,appctx.SEMop.grad,appctx.SEMop.grad,&appctx);CHKERRQ(ierr);
/*
For linear problems with a time-dependent f(u,t) in the equation
u_t = f(u,t), the user provides the discretized right-hand-side
as a time-dependent matrix.
*/
ierr = MatDuplicate(appctx.SEMop.stiff,MAT_COPY_VALUES,&appctx.SEMop.keptstiff);CHKERRQ(ierr);
/* attach the null space to the matrix, this probably is not needed but does no harm */
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,NULL,&nsp);CHKERRQ(ierr);
ierr = MatSetNullSpace(appctx.SEMop.stiff,nsp);CHKERRQ(ierr);
ierr = MatSetNullSpace(appctx.SEMop.keptstiff,nsp);CHKERRQ(ierr);
ierr = MatNullSpaceTest(nsp,appctx.SEMop.stiff,NULL);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nsp);CHKERRQ(ierr);
/* attach the null space to the matrix, this probably is not needed but does no harm */
ierr = MatNullSpaceCreate(PETSC_COMM_WORLD,PETSC_TRUE,0,NULL,&nsp);CHKERRQ(ierr);
ierr = MatSetNullSpace(appctx.SEMop.grad,nsp);CHKERRQ(ierr);
ierr = MatNullSpaceTest(nsp,appctx.SEMop.grad,NULL);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nsp);CHKERRQ(ierr);
/* Create the TS solver that solves the ODE and its adjoint; set its options */
ierr = TSCreate(PETSC_COMM_WORLD,&appctx.ts);CHKERRQ(ierr);
ierr = TSSetProblemType(appctx.ts,TS_NONLINEAR);CHKERRQ(ierr);
ierr = TSSetType(appctx.ts,TSRK);CHKERRQ(ierr);
ierr = TSSetDM(appctx.ts,appctx.da);CHKERRQ(ierr);
ierr = TSSetTime(appctx.ts,0.0);CHKERRQ(ierr);
ierr = TSSetTimeStep(appctx.ts,appctx.initial_dt);CHKERRQ(ierr);
ierr = TSSetMaxSteps(appctx.ts,appctx.param.steps);CHKERRQ(ierr);
ierr = TSSetMaxTime(appctx.ts,appctx.param.Tend);CHKERRQ(ierr);
ierr = TSSetExactFinalTime(appctx.ts,TS_EXACTFINALTIME_MATCHSTEP);CHKERRQ(ierr);
ierr = TSSetTolerances(appctx.ts,1e-7,NULL,1e-7,NULL);CHKERRQ(ierr);
ierr = TSSetSaveTrajectory(appctx.ts);CHKERRQ(ierr);
ierr = TSSetFromOptions(appctx.ts);CHKERRQ(ierr);
ierr = TSSetRHSFunction(appctx.ts,NULL,RHSFunction,&appctx);CHKERRQ(ierr);
ierr = TSSetRHSJacobian(appctx.ts,appctx.SEMop.stiff,appctx.SEMop.stiff,RHSJacobian,&appctx);CHKERRQ(ierr);
/* Set Initial conditions for the problem */
ierr = TrueSolution(appctx.ts,0,appctx.dat.curr_sol,&appctx);CHKERRQ(ierr);
ierr = TSSetSolutionFunction(appctx.ts,(PetscErrorCode (*)(TS,PetscReal,Vec,void *))TrueSolution,&appctx);CHKERRQ(ierr);
ierr = TSSetTime(appctx.ts,0.0);CHKERRQ(ierr);
ierr = TSSetStepNumber(appctx.ts,0);CHKERRQ(ierr);
ierr = TSSolve(appctx.ts,appctx.dat.curr_sol);CHKERRQ(ierr);
ierr = MatDestroy(&appctx.SEMop.stiff);CHKERRQ(ierr);
ierr = MatDestroy(&appctx.SEMop.keptstiff);CHKERRQ(ierr);
ierr = MatDestroy(&appctx.SEMop.grad);CHKERRQ(ierr);
ierr = VecDestroy(&appctx.SEMop.grid);CHKERRQ(ierr);
ierr = VecDestroy(&appctx.SEMop.mass);CHKERRQ(ierr);
ierr = VecDestroy(&appctx.dat.curr_sol);CHKERRQ(ierr);
ierr = PetscGLLDestroy(&appctx.SEMop.gll);CHKERRQ(ierr);
ierr = DMDestroy(&appctx.da);CHKERRQ(ierr);
ierr = TSDestroy(&appctx.ts);CHKERRQ(ierr);
/*
Always call PetscFinalize() before exiting a program. This routine
- finalizes the PETSc libraries as well as MPI
- provides summary and diagnostic information if certain runtime
options are chosen (e.g., -log_summary).
*/
ierr = PetscFinalize();
return ierr;
}
/*@
KSPSetFromOptions - Sets KSP options from the options database.
This routine must be called before KSPSetUp() if the user is to be
allowed to set the Krylov type.
Collective on KSP
Input Parameters:
. ksp - the Krylov space context
Options Database Keys:
+ -ksp_max_it - maximum number of linear iterations
. -ksp_rtol rtol - relative tolerance used in default determination of convergence, i.e.
if residual norm decreases by this factor than convergence is declared
. -ksp_atol abstol - absolute tolerance used in default convergence test, i.e. if residual
norm is less than this then convergence is declared
. -ksp_divtol tol - if residual norm increases by this factor than divergence is declared
. -ksp_converged_use_initial_residual_norm - see KSPConvergedDefaultSetUIRNorm()
. -ksp_converged_use_min_initial_residual_norm - see KSPConvergedDefaultSetUMIRNorm()
. -ksp_norm_type - none - skip norms used in convergence tests (useful only when not using
convergence test (say you always want to run with 5 iterations) to
save on communication overhead
preconditioned - default for left preconditioning
unpreconditioned - see KSPSetNormType()
natural - see KSPSetNormType()
. -ksp_check_norm_iteration it - do not compute residual norm until iteration number it (does compute at 0th iteration)
works only for PCBCGS, PCIBCGS and and PCCG
. -ksp_lag_norm - compute the norm of the residual for the ith iteration on the i+1 iteration; this means that one can use
the norm of the residual for convergence test WITHOUT an extra MPI_Allreduce() limiting global synchronizations.
This will require 1 more iteration of the solver than usual.
. -ksp_fischer_guess <model,size> - uses the Fischer initial guess generator for repeated linear solves
. -ksp_constant_null_space - assume the operator (matrix) has the constant vector in its null space
. -ksp_test_null_space - tests the null space set with KSPSetNullSpace() to see if it truly is a null space
. -ksp_knoll - compute initial guess by applying the preconditioner to the right hand side
. -ksp_monitor_cancel - cancel all previous convergene monitor routines set
. -ksp_monitor <optional filename> - print residual norm at each iteration
. -ksp_monitor_lg_residualnorm - plot residual norm at each iteration
. -ksp_monitor_solution - plot solution at each iteration
- -ksp_monitor_singular_value - monitor extremem singular values at each iteration
Notes:
To see all options, run your program with the -help option
or consult Users-Manual: ch_ksp
Level: beginner
.keywords: KSP, set, from, options, database
.seealso: KSPSetUseFischerGuess()
@*/
PetscErrorCode KSPSetFromOptions(KSP ksp)
{
PetscErrorCode ierr;
PetscInt indx;
const char *convtests[] = {"default","skip"};
char type[256], monfilename[PETSC_MAX_PATH_LEN];
PetscViewer monviewer;
PetscBool flg,flag,reuse;
PetscInt model[2]={0,0},nmax;
KSPNormType normtype;
PCSide pcside;
void *ctx;
PetscFunctionBegin;
PetscValidHeaderSpecific(ksp,KSP_CLASSID,1);
if (!ksp->pc) {ierr = KSPGetPC(ksp,&ksp->pc);CHKERRQ(ierr);}
ierr = PCSetFromOptions(ksp->pc);CHKERRQ(ierr);
if (!KSPRegisterAllCalled) {ierr = KSPRegisterAll();CHKERRQ(ierr);}
ierr = PetscObjectOptionsBegin((PetscObject)ksp);CHKERRQ(ierr);
ierr = PetscOptionsFList("-ksp_type","Krylov method","KSPSetType",KSPList,(char*)(((PetscObject)ksp)->type_name ? ((PetscObject)ksp)->type_name : KSPGMRES),type,256,&flg);CHKERRQ(ierr);
if (flg) {
ierr = KSPSetType(ksp,type);CHKERRQ(ierr);
}
/*
Set the type if it was never set.
*/
if (!((PetscObject)ksp)->type_name) {
ierr = KSPSetType(ksp,KSPGMRES);CHKERRQ(ierr);
}
ierr = PetscOptionsInt("-ksp_max_it","Maximum number of iterations","KSPSetTolerances",ksp->max_it,&ksp->max_it,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-ksp_rtol","Relative decrease in residual norm","KSPSetTolerances",ksp->rtol,&ksp->rtol,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-ksp_atol","Absolute value of residual norm","KSPSetTolerances",ksp->abstol,&ksp->abstol,NULL);CHKERRQ(ierr);
ierr = PetscOptionsReal("-ksp_divtol","Residual norm increase cause divergence","KSPSetTolerances",ksp->divtol,&ksp->divtol,NULL);CHKERRQ(ierr);
flag = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_converged_use_initial_residual_norm","Use initial residual residual norm for computing relative convergence","KSPConvergedDefaultSetUIRNorm",flag,&flag,NULL);CHKERRQ(ierr);
if (flag) {ierr = KSPConvergedDefaultSetUIRNorm(ksp);CHKERRQ(ierr);}
flag = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_converged_use_min_initial_residual_norm","Use minimum of initial residual norm and b for computing relative convergence","KSPConvergedDefaultSetUMIRNorm",flag,&flag,NULL);CHKERRQ(ierr);
if (flag) {ierr = KSPConvergedDefaultSetUMIRNorm(ksp);CHKERRQ(ierr);}
ierr = KSPGetInitialGuessNonzero(ksp,&flag);CHKERRQ(ierr);
ierr = PetscOptionsBool("-ksp_initial_guess_nonzero","Use the contents of the solution vector for initial guess","KSPSetInitialNonzero",flag,&flag,&flg);CHKERRQ(ierr);
if (flg) {
ierr = KSPSetInitialGuessNonzero(ksp,flag);CHKERRQ(ierr);
}
ierr = PCGetReusePreconditioner(ksp->pc,&reuse);CHKERRQ(ierr);
ierr = PetscOptionsBool("-ksp_reuse_preconditioner","Use initial preconditioner and don't ever compute a new one ","KSPReusePreconditioner",reuse,&reuse,NULL);CHKERRQ(ierr);
ierr = KSPSetReusePreconditioner(ksp,reuse);CHKERRQ(ierr);
ierr = PetscOptionsBool("-ksp_knoll","Use preconditioner applied to b for initial guess","KSPSetInitialGuessKnoll",ksp->guess_knoll,&ksp->guess_knoll,NULL);CHKERRQ(ierr);
ierr = PetscOptionsBool("-ksp_error_if_not_converged","Generate error if solver does not converge","KSPSetErrorIfNotConverged",ksp->errorifnotconverged,&ksp->errorifnotconverged,NULL);CHKERRQ(ierr);
nmax = 2;
ierr = PetscOptionsIntArray("-ksp_fischer_guess","Use Paul Fischer's algorithm for initial guess","KSPSetUseFischerGuess",model,&nmax,&flag);CHKERRQ(ierr);
if (flag) {
if (nmax != 2) SETERRQ(PetscObjectComm((PetscObject)ksp),PETSC_ERR_ARG_OUTOFRANGE,"Must pass in model,size as arguments");
ierr = KSPSetUseFischerGuess(ksp,model[0],model[1]);CHKERRQ(ierr);
}
ierr = PetscOptionsEList("-ksp_convergence_test","Convergence test","KSPSetConvergenceTest",convtests,2,"default",&indx,&flg);CHKERRQ(ierr);
if (flg) {
switch (indx) {
case 0:
ierr = KSPConvergedDefaultCreate(&ctx);CHKERRQ(ierr);
ierr = KSPSetConvergenceTest(ksp,KSPConvergedDefault,ctx,KSPConvergedDefaultDestroy);CHKERRQ(ierr);
break;
case 1: ierr = KSPSetConvergenceTest(ksp,KSPConvergedSkip,NULL,NULL);CHKERRQ(ierr); break;
}
}
ierr = KSPSetUpNorms_Private(ksp,&normtype,&pcside);CHKERRQ(ierr);
ierr = PetscOptionsEnum("-ksp_norm_type","KSP Norm type","KSPSetNormType",KSPNormTypes,(PetscEnum)normtype,(PetscEnum*)&normtype,&flg);CHKERRQ(ierr);
if (flg) { ierr = KSPSetNormType(ksp,normtype);CHKERRQ(ierr); }
ierr = PetscOptionsInt("-ksp_check_norm_iteration","First iteration to compute residual norm","KSPSetCheckNormIteration",ksp->chknorm,&ksp->chknorm,NULL);CHKERRQ(ierr);
flag = ksp->lagnorm;
ierr = PetscOptionsBool("-ksp_lag_norm","Lag the calculation of the residual norm","KSPSetLagNorm",flag,&flag,&flg);CHKERRQ(ierr);
if (flg) {
ierr = KSPSetLagNorm(ksp,flag);CHKERRQ(ierr);
}
ierr = KSPGetDiagonalScale(ksp,&flag);CHKERRQ(ierr);
ierr = PetscOptionsBool("-ksp_diagonal_scale","Diagonal scale matrix before building preconditioner","KSPSetDiagonalScale",flag,&flag,&flg);CHKERRQ(ierr);
if (flg) {
ierr = KSPSetDiagonalScale(ksp,flag);CHKERRQ(ierr);
}
ierr = KSPGetDiagonalScaleFix(ksp,&flag);CHKERRQ(ierr);
ierr = PetscOptionsBool("-ksp_diagonal_scale_fix","Fix diagonally scaled matrix after solve","KSPSetDiagonalScaleFix",flag,&flag,&flg);CHKERRQ(ierr);
if (flg) {
ierr = KSPSetDiagonalScaleFix(ksp,flag);CHKERRQ(ierr);
}
flg = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_constant_null_space","Add constant null space to Krylov solver","KSPSetNullSpace",flg,&flg,NULL);CHKERRQ(ierr);
if (flg) {
MatNullSpace nsp;
ierr = MatNullSpaceCreate(PetscObjectComm((PetscObject)ksp),PETSC_TRUE,0,0,&nsp);CHKERRQ(ierr);
ierr = KSPSetNullSpace(ksp,nsp);CHKERRQ(ierr);
ierr = MatNullSpaceDestroy(&nsp);CHKERRQ(ierr);
}
/* option is actually checked in KSPSetUp(), just here so goes into help message */
if (ksp->nullsp) {
ierr = PetscOptionsName("-ksp_test_null_space","Is provided null space correct","None",&flg);CHKERRQ(ierr);
}
/*
Prints reason for convergence or divergence of each linear solve
*/
flg = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_converged_reason","Print reason for converged or diverged","KSPSolve",flg,&flg,NULL);CHKERRQ(ierr);
if (flg) ksp->printreason = PETSC_TRUE;
flg = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_monitor_cancel","Remove any hardwired monitor routines","KSPMonitorCancel",flg,&flg,NULL);CHKERRQ(ierr);
/* -----------------------------------------------------------------------*/
/*
Cancels all monitors hardwired into code before call to KSPSetFromOptions()
*/
if (flg) {
ierr = KSPMonitorCancel(ksp);CHKERRQ(ierr);
}
/*
Prints preconditioned residual norm at each iteration
*/
ierr = PetscOptionsString("-ksp_monitor","Monitor preconditioned residual norm","KSPMonitorSet","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
if (flg) {
ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ksp),monfilename,&monviewer);CHKERRQ(ierr);
ierr = KSPMonitorSet(ksp,KSPMonitorDefault,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
}
/*
Prints preconditioned residual norm at each iteration
*/
ierr = PetscOptionsString("-ksp_monitor_range","Monitor percent of residual entries more than 10 percent of max","KSPMonitorRange","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
if (flg) {
ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ksp),monfilename,&monviewer);CHKERRQ(ierr);
ierr = KSPMonitorSet(ksp,KSPMonitorRange,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
}
ierr = PetscObjectTypeCompare((PetscObject)ksp->pc,PCKSP,&flg);CHKERRQ(ierr);
ierr = PetscObjectTypeCompare((PetscObject)ksp->pc,PCBJACOBI,&flag);CHKERRQ(ierr);
if (flg || flag) {
/* A hack for using dynamic tolerance in preconditioner */
ierr = PetscOptionsString("-sub_ksp_dynamic_tolerance","Use dynamic tolerance for PC if PC is a KSP","KSPMonitorDynamicTolerance","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
if (flg) {
KSPDynTolCtx *scale = NULL;
PetscReal defaultv = 1.0;
ierr = PetscMalloc1(1,&scale);CHKERRQ(ierr);
scale->bnrm = -1.0;
scale->coef = defaultv;
ierr = PetscOptionsReal("-sub_ksp_dynamic_tolerance_param","Parameter of dynamic tolerance for inner PCKSP","KSPMonitorDynamicToleranceParam",defaultv,&(scale->coef),&flg);CHKERRQ(ierr);
ierr = KSPMonitorSet(ksp,KSPMonitorDynamicTolerance,scale,KSPMonitorDynamicToleranceDestroy);CHKERRQ(ierr);
}
}
/*
Plots the vector solution
*/
flg = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_monitor_solution","Monitor solution graphically","KSPMonitorSet",flg,&flg,NULL);CHKERRQ(ierr);
if (flg) {
ierr = KSPMonitorSet(ksp,KSPMonitorSolution,NULL,NULL);CHKERRQ(ierr);
}
/*
Prints preconditioned and true residual norm at each iteration
*/
ierr = PetscOptionsString("-ksp_monitor_true_residual","Monitor true residual norm","KSPMonitorSet","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
if (flg) {
ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ksp),monfilename,&monviewer);CHKERRQ(ierr);
ierr = KSPMonitorSet(ksp,KSPMonitorTrueResidualNorm,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
}
/*
Prints with max norm at each iteration
*/
ierr = PetscOptionsString("-ksp_monitor_max","Monitor true residual max norm","KSPMonitorSet","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
if (flg) {
ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ksp),monfilename,&monviewer);CHKERRQ(ierr);
ierr = KSPMonitorSet(ksp,KSPMonitorTrueResidualMaxNorm,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
}
/*
Prints extreme eigenvalue estimates at each iteration
*/
ierr = PetscOptionsString("-ksp_monitor_singular_value","Monitor singular values","KSPMonitorSet","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
if (flg) {
ierr = KSPSetComputeSingularValues(ksp,PETSC_TRUE);CHKERRQ(ierr);
ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ksp),monfilename,&monviewer);CHKERRQ(ierr);
ierr = KSPMonitorSet(ksp,KSPMonitorSingularValue,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
}
/*
Prints preconditioned residual norm with fewer digits
*/
ierr = PetscOptionsString("-ksp_monitor_short","Monitor preconditioned residual norm with fewer digits","KSPMonitorSet","stdout",monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
if (flg) {
ierr = PetscViewerASCIIOpen(PetscObjectComm((PetscObject)ksp),monfilename,&monviewer);CHKERRQ(ierr);
ierr = KSPMonitorSet(ksp,KSPMonitorDefaultShort,monviewer,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
}
/*
Calls Python function
*/
ierr = PetscOptionsString("-ksp_monitor_python","Use Python function","KSPMonitorSet",0,monfilename,PETSC_MAX_PATH_LEN,&flg);CHKERRQ(ierr);
if (flg) {ierr = PetscPythonMonitorSet((PetscObject)ksp,monfilename);CHKERRQ(ierr);}
/*
Graphically plots preconditioned residual norm
*/
flg = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_monitor_lg_residualnorm","Monitor graphically preconditioned residual norm","KSPMonitorSet",flg,&flg,NULL);CHKERRQ(ierr);
if (flg) {
PetscDrawLG ctx;
ierr = KSPMonitorLGResidualNormCreate(0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,&ctx);CHKERRQ(ierr);
ierr = KSPMonitorSet(ksp,KSPMonitorLGResidualNorm,ctx,(PetscErrorCode (*)(void**))KSPMonitorLGResidualNormDestroy);CHKERRQ(ierr);
}
/*
Graphically plots preconditioned and true residual norm
*/
flg = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_monitor_lg_true_residualnorm","Monitor graphically true residual norm","KSPMonitorSet",flg,&flg,NULL);CHKERRQ(ierr);
if (flg) {
PetscDrawLG ctx;
ierr = KSPMonitorLGTrueResidualNormCreate(PetscObjectComm((PetscObject)ksp),0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,&ctx);CHKERRQ(ierr);
ierr = KSPMonitorSet(ksp,KSPMonitorLGTrueResidualNorm,ctx,(PetscErrorCode (*)(void**))KSPMonitorLGTrueResidualNormDestroy);CHKERRQ(ierr);
}
/*
Graphically plots preconditioned residual norm and range of residual element values
*/
flg = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_monitor_lg_range","Monitor graphically range of preconditioned residual norm","KSPMonitorSet",flg,&flg,NULL);CHKERRQ(ierr);
if (flg) {
PetscViewer ctx;
ierr = PetscViewerDrawOpen(PetscObjectComm((PetscObject)ksp),0,0,PETSC_DECIDE,PETSC_DECIDE,300,300,&ctx);CHKERRQ(ierr);
ierr = KSPMonitorSet(ksp,KSPMonitorLGRange,ctx,(PetscErrorCode (*)(void**))PetscViewerDestroy);CHKERRQ(ierr);
}
#if defined(PETSC_HAVE_SAWS)
/*
Publish convergence information using AMS
*/
flg = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_monitor_saws","Publish KSP progress using SAWs","KSPMonitorSet",flg,&flg,NULL);CHKERRQ(ierr);
if (flg) {
void *ctx;
ierr = KSPMonitorSAWsCreate(ksp,&ctx);CHKERRQ(ierr);
ierr = KSPMonitorSet(ksp,KSPMonitorSAWs,ctx,KSPMonitorSAWsDestroy);CHKERRQ(ierr);
ierr = KSPSetComputeSingularValues(ksp,PETSC_TRUE);CHKERRQ(ierr);
}
#endif
/* -----------------------------------------------------------------------*/
ierr = KSPSetUpNorms_Private(ksp,&normtype,&pcside);CHKERRQ(ierr);
ierr = PetscOptionsEnum("-ksp_pc_side","KSP preconditioner side","KSPSetPCSide",PCSides,(PetscEnum)pcside,(PetscEnum*)&pcside,&flg);CHKERRQ(ierr);
if (flg) {ierr = KSPSetPCSide(ksp,pcside);CHKERRQ(ierr);}
flg = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_compute_singularvalues","Compute singular values of preconditioned operator","KSPSetComputeSingularValues",flg,&flg,NULL);CHKERRQ(ierr);
if (flg) { ierr = KSPSetComputeSingularValues(ksp,PETSC_TRUE);CHKERRQ(ierr); }
flg = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_compute_eigenvalues","Compute eigenvalues of preconditioned operator","KSPSetComputeSingularValues",flg,&flg,NULL);CHKERRQ(ierr);
if (flg) { ierr = KSPSetComputeSingularValues(ksp,PETSC_TRUE);CHKERRQ(ierr); }
flg = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_plot_eigenvalues","Scatter plot extreme eigenvalues","KSPSetComputeSingularValues",flg,&flg,NULL);CHKERRQ(ierr);
if (flg) { ierr = KSPSetComputeSingularValues(ksp,PETSC_TRUE);CHKERRQ(ierr); }
#if defined(PETSC_HAVE_SAWS)
{
PetscBool set;
flg = PETSC_FALSE;
ierr = PetscOptionsBool("-ksp_saws_block","Block for SAWs at end of KSPSolve","PetscObjectSAWsBlock",((PetscObject)ksp)->amspublishblock,&flg,&set);CHKERRQ(ierr);
if (set) {
ierr = PetscObjectSAWsSetBlock((PetscObject)ksp,flg);CHKERRQ(ierr);
}
}
#endif
if (ksp->ops->setfromoptions) {
ierr = (*ksp->ops->setfromoptions)(ksp);CHKERRQ(ierr);
}
/* process any options handlers added with PetscObjectAddOptionsHandler() */
ierr = PetscObjectProcessOptionsHandlers((PetscObject)ksp);CHKERRQ(ierr);
ierr = PetscOptionsEnd();CHKERRQ(ierr);
PetscFunctionReturn(0);
}
