static PetscErrorCode VecDotNorm2_Nest(Vec x,Vec y,PetscScalar *dp, PetscScalar *nm)
{
Vec_Nest *bx = (Vec_Nest*)x->data;
Vec_Nest *by = (Vec_Nest*)y->data;
PetscInt i,nr;
PetscScalar x_dot_y,_dp,_nm;
PetscReal norm2_y;
PetscErrorCode ierr;
PetscFunctionBegin;
nr = bx->nb;
_dp = 0.0;
_nm = 0.0;
for (i=0; i<nr; i++) {
ierr = VecDotNorm2(bx->v[i],by->v[i],&x_dot_y,&norm2_y);CHKERRQ(ierr);
_dp += x_dot_y;
_nm += norm2_y;
}
*dp = _dp;
*nm = _nm;
PetscFunctionReturn(0);
}
PetscErrorCode KSPSolve_GCR_cycle( KSP ksp )
{
KSP_GCR *ctx = (KSP_GCR*)ksp->data;
PetscErrorCode ierr;
PetscScalar r_dot_v;
Mat A, B;
PC pc;
Vec s,v,r;
PetscReal norm_r,nrm;
PetscInt k, i, restart;
Vec x;
PetscReal res;
PetscFunctionBegin;
restart = ctx->restart;
ierr = KSPGetPC( ksp, &pc );CHKERRQ(ierr);
ierr = KSPGetOperators( ksp, &A, &B, 0 );CHKERRQ(ierr);
x = ksp->vec_sol;
r = ctx->R;
for ( k=0; k<restart; k++ ) {
v = ctx->VV[k];
s = ctx->SS[k];
if (ctx->modifypc) {
ierr = (*ctx->modifypc)(ksp,ksp->its,ksp->rnorm,ctx->modifypc_ctx);CHKERRQ(ierr);
}
ierr = PCApply( pc, r, s );CHKERRQ(ierr); /* s = B^{-1} r */
ierr = MatMult( A, s, v );CHKERRQ(ierr); /* v = A s */
ierr = VecMDot( v,k, ctx->VV, ctx->val );CHKERRQ(ierr);
for (i=0; i<k; i++) ctx->val[i] = -ctx->val[i];
ierr = VecMAXPY(v,k,ctx->val,ctx->VV);CHKERRQ(ierr); /* v = v - sum_{i=0}^{k-1} alpha_i v_i */
ierr = VecMAXPY(s,k,ctx->val,ctx->SS);CHKERRQ(ierr); /* s = s - sum_{i=0}^{k-1} alpha_i s_i */
ierr = VecDotNorm2(r,v,&r_dot_v,&nrm);CHKERRQ(ierr);
nrm = PetscSqrtReal(nrm);
r_dot_v = r_dot_v/nrm;
ierr = VecScale( v, 1.0/nrm );CHKERRQ(ierr);
ierr = VecScale( s, 1.0/nrm );CHKERRQ(ierr);
ierr = VecAXPY( x, r_dot_v, s );CHKERRQ(ierr);
ierr = VecAXPY( r, -r_dot_v, v );CHKERRQ(ierr);
if (ksp->its > ksp->chknorm ) {
ierr = VecNorm( r, NORM_2, &norm_r );CHKERRQ(ierr);
}
/* update the local counter and the global counter */
ksp->its++;
res = norm_r;
ksp->rnorm = res;
KSPLogResidualHistory(ksp,res);
ierr = KSPMonitor(ksp,ksp->its,res);CHKERRQ(ierr);
if ( ksp->its > ksp->chknorm ) {
ierr = (*ksp->converged)(ksp,ksp->its,res,&ksp->reason,ksp->cnvP);CHKERRQ(ierr);
if (ksp->reason) break;
}
if ( ksp->its >= ksp->max_it ) {
ksp->reason = KSP_CONVERGED_ITS;
break;
}
}
ctx->n_restarts++;
PetscFunctionReturn(0);
}
PetscErrorCode test_axpy_dot_max( void )
{
Vec x1,y1, x2,y2;
Vec tmp_buf[2];
Vec X, Y;
PetscReal real,real2;
PetscScalar scalar;
PetscInt index;
PetscErrorCode ierr;
PetscFunctionBegin;
PetscPrintf( PETSC_COMM_WORLD, "\n\n============== %s ==============\n", PETSC_FUNCTION_NAME );
gen_test_vector( PETSC_COMM_WORLD, 4, 0, 1, &x1 );
gen_test_vector( PETSC_COMM_WORLD, 5, 10, 2, &x2 );
gen_test_vector( PETSC_COMM_WORLD, 4, 4, 3, &y1 );
gen_test_vector( PETSC_COMM_WORLD, 5, 5, 1, &y2 );
tmp_buf[0] = x1;
tmp_buf[1] = x2;
ierr = VecCreateNest(PETSC_COMM_WORLD,2,PETSC_NULL,tmp_buf,&X);CHKERRQ(ierr);
ierr = VecAssemblyBegin(X);CHKERRQ(ierr);
ierr = VecAssemblyEnd(X);CHKERRQ(ierr);
ierr = VecDestroy(&x1);CHKERRQ(ierr);
ierr = VecDestroy(&x2);CHKERRQ(ierr);
tmp_buf[0] = y1;
tmp_buf[1] = y2;
ierr = VecCreateNest(PETSC_COMM_WORLD,2,PETSC_NULL,tmp_buf,&Y);CHKERRQ(ierr);
ierr = VecAssemblyBegin(Y);CHKERRQ(ierr);
ierr = VecAssemblyEnd(Y);CHKERRQ(ierr);
ierr = VecDestroy(&y1);CHKERRQ(ierr);
ierr = VecDestroy(&y2);CHKERRQ(ierr);
PetscPrintf( PETSC_COMM_WORLD, "VecAXPY \n");
ierr = VecAXPY( Y, 1.0, X ); /* Y <- a X + Y */
ierr = VecNestGetSubVec( Y, 0, &y1 );CHKERRQ(ierr);
ierr = VecNestGetSubVec( Y, 1, &y2 );CHKERRQ(ierr);
PetscPrintf( PETSC_COMM_WORLD, "(1) y1 = \n" );
ierr = VecView( y1, PETSC_VIEWER_STDOUT_WORLD );CHKERRQ(ierr);
PetscPrintf( PETSC_COMM_WORLD, "(1) y2 = \n" );
ierr = VecView( y2, PETSC_VIEWER_STDOUT_WORLD );CHKERRQ(ierr);
ierr = VecDot( X,Y, &scalar );CHKERRQ(ierr);
PetscPrintf( PETSC_COMM_WORLD, "X.Y = %lf + %lfi \n", PetscRealPart(scalar), PetscImaginaryPart(scalar) );
ierr = VecDotNorm2( X,Y, &scalar, &real2 );CHKERRQ(ierr);
PetscPrintf( PETSC_COMM_WORLD, "X.Y = %lf + %lfi norm2(Y) = %lf\n", PetscRealPart(scalar), PetscImaginaryPart(scalar), real2);
ierr = VecAXPY( Y, 1.0, X ); /* Y <- a X + Y */
ierr = VecNestGetSubVec( Y, 0, &y1 );CHKERRQ(ierr);
ierr = VecNestGetSubVec( Y, 1, &y2 );CHKERRQ(ierr);
PetscPrintf( PETSC_COMM_WORLD, "(2) y1 = \n" );
ierr = VecView( y1, PETSC_VIEWER_STDOUT_WORLD );CHKERRQ(ierr);
PetscPrintf( PETSC_COMM_WORLD, "(2) y2 = \n" );
ierr = VecView( y2, PETSC_VIEWER_STDOUT_WORLD );CHKERRQ(ierr);
ierr = VecDot( X,Y, &scalar );CHKERRQ(ierr);
PetscPrintf( PETSC_COMM_WORLD, "X.Y = %lf + %lfi \n", PetscRealPart(scalar), PetscImaginaryPart(scalar) );
ierr = VecDotNorm2( X,Y, &scalar, &real2 );CHKERRQ(ierr);
PetscPrintf( PETSC_COMM_WORLD, "X.Y = %lf + %lfi norm2(Y) = %lf\n", PetscRealPart(scalar), PetscImaginaryPart(scalar), real2);
ierr = VecMax( X, &index, &real );CHKERRQ(ierr);
PetscPrintf( PETSC_COMM_WORLD, "(max-X) = %f : index = %d \n", real, index );
ierr = VecMin( X, &index, &real );CHKERRQ(ierr);
PetscPrintf( PETSC_COMM_WORLD, "(min-X) = %f : index = %d \n", real, index );
ierr = VecDestroy(&X);CHKERRQ(ierr);
ierr = VecDestroy(&Y);CHKERRQ(ierr);
PetscFunctionReturn(0);
}
PetscErrorCode KSPSolve_Richardson(KSP ksp)
{
PetscErrorCode ierr;
PetscInt i,maxit;
PetscReal rnorm = 0.0,abr;
PetscScalar scale,rdot;
Vec x,b,r,z,w = NULL,y = NULL;
PetscInt xs, ws;
Mat Amat,Pmat;
KSP_Richardson *richardsonP = (KSP_Richardson*)ksp->data;
PetscBool exists,diagonalscale;
PetscFunctionBegin;
ierr = PCGetDiagonalScale(ksp->pc,&diagonalscale);CHKERRQ(ierr);
if (diagonalscale) SETERRQ1(PetscObjectComm((PetscObject)ksp),PETSC_ERR_SUP,"Krylov method %s does not support diagonal scaling",((PetscObject)ksp)->type_name);
ksp->its = 0;
ierr = PCGetOperators(ksp->pc,&Amat,&Pmat);CHKERRQ(ierr);
x = ksp->vec_sol;
b = ksp->vec_rhs;
ierr = VecGetSize(x,&xs);CHKERRQ(ierr);
ierr = VecGetSize(ksp->work[0],&ws);CHKERRQ(ierr);
if (xs != ws) {
if (richardsonP->selfscale) {
ierr = KSPSetWorkVecs(ksp,4);CHKERRQ(ierr);
} else {
ierr = KSPSetWorkVecs(ksp,2);CHKERRQ(ierr);
}
}
r = ksp->work[0];
z = ksp->work[1];
if (richardsonP->selfscale) {
w = ksp->work[2];
y = ksp->work[3];
}
maxit = ksp->max_it;
/* if user has provided fast Richardson code use that */
ierr = PCApplyRichardsonExists(ksp->pc,&exists);CHKERRQ(ierr);
if (exists && !ksp->numbermonitors && !ksp->transpose_solve & !ksp->nullsp) {
PCRichardsonConvergedReason reason;
ierr = PCApplyRichardson(ksp->pc,b,x,r,ksp->rtol,ksp->abstol,ksp->divtol,maxit,ksp->guess_zero,&ksp->its,&reason);CHKERRQ(ierr);
ksp->reason = (KSPConvergedReason)reason;
PetscFunctionReturn(0);
}
scale = richardsonP->scale;
if (!ksp->guess_zero) { /* r <- b - A x */
ierr = KSP_MatMult(ksp,Amat,x,r);CHKERRQ(ierr);
ierr = VecAYPX(r,-1.0,b);CHKERRQ(ierr);
} else {
ierr = VecCopy(b,r);CHKERRQ(ierr);
}
ksp->its = 0;
if (richardsonP->selfscale) {
ierr = KSP_PCApply(ksp,r,z);CHKERRQ(ierr); /* z <- B r */
for (i=0; i<maxit; i++) {
if (ksp->normtype == KSP_NORM_UNPRECONDITIONED) {
ierr = VecNorm(r,NORM_2,&rnorm);CHKERRQ(ierr); /* rnorm <- r'*r */
ierr = KSPMonitor(ksp,i,rnorm);CHKERRQ(ierr);
ksp->rnorm = rnorm;
ierr = KSPLogResidualHistory(ksp,rnorm);CHKERRQ(ierr);
ierr = (*ksp->converged)(ksp,i,rnorm,&ksp->reason,ksp->cnvP);CHKERRQ(ierr);
if (ksp->reason) break;
} else if (ksp->normtype == KSP_NORM_PRECONDITIONED) {
ierr = VecNorm(z,NORM_2,&rnorm);CHKERRQ(ierr); /* rnorm <- z'*z */
ierr = KSPMonitor(ksp,i,rnorm);CHKERRQ(ierr);
ksp->rnorm = rnorm;
ierr = KSPLogResidualHistory(ksp,rnorm);CHKERRQ(ierr);
ierr = (*ksp->converged)(ksp,i,rnorm,&ksp->reason,ksp->cnvP);CHKERRQ(ierr);
if (ksp->reason) break;
}
ierr = KSP_PCApplyBAorAB(ksp,z,y,w);CHKERRQ(ierr); /* y = BAz = BABr */
ierr = VecDotNorm2(z,y,&rdot,&abr);CHKERRQ(ierr); /* rdot = (Br)^T(BABR); abr = (BABr)^T (BABr) */
scale = rdot/abr;
ierr = PetscInfo1(ksp,"Self-scale factor %g\n",(double)PetscRealPart(scale));CHKERRQ(ierr);
ierr = VecAXPY(x,scale,z);CHKERRQ(ierr); /* x <- x + scale z */
ierr = VecAXPY(r,-scale,w);CHKERRQ(ierr); /* r <- r - scale*Az */
ierr = VecAXPY(z,-scale,y);CHKERRQ(ierr); /* z <- z - scale*y */
ksp->its++;
}
} else {
for (i=0; i<maxit; i++) {
if (ksp->normtype == KSP_NORM_UNPRECONDITIONED) {
ierr = VecNorm(r,NORM_2,&rnorm);CHKERRQ(ierr); /* rnorm <- r'*r */
ierr = KSPMonitor(ksp,i,rnorm);CHKERRQ(ierr);
ksp->rnorm = rnorm;
ierr = KSPLogResidualHistory(ksp,rnorm);CHKERRQ(ierr);
ierr = (*ksp->converged)(ksp,i,rnorm,&ksp->reason,ksp->cnvP);CHKERRQ(ierr);
if (ksp->reason) break;
}
ierr = KSP_PCApply(ksp,r,z);CHKERRQ(ierr); /* z <- B r */
if (ksp->normtype == KSP_NORM_PRECONDITIONED) {
ierr = VecNorm(z,NORM_2,&rnorm);CHKERRQ(ierr); /* rnorm <- z'*z */
ierr = KSPMonitor(ksp,i,rnorm);CHKERRQ(ierr);
ksp->rnorm = rnorm;
ierr = KSPLogResidualHistory(ksp,rnorm);CHKERRQ(ierr);
ierr = (*ksp->converged)(ksp,i,rnorm,&ksp->reason,ksp->cnvP);CHKERRQ(ierr);
if (ksp->reason) break;
}
ierr = VecAXPY(x,scale,z);CHKERRQ(ierr); /* x <- x + scale z */
ksp->its++;
if (i+1 < maxit || ksp->normtype != KSP_NORM_NONE) {
ierr = KSP_MatMult(ksp,Amat,x,r);CHKERRQ(ierr); /* r <- b - Ax */
ierr = VecAYPX(r,-1.0,b);CHKERRQ(ierr);
}
}
}
if (!ksp->reason) {
if (ksp->normtype != KSP_NORM_NONE) {
if (ksp->normtype == KSP_NORM_UNPRECONDITIONED) {
ierr = VecNorm(r,NORM_2,&rnorm);CHKERRQ(ierr); /* rnorm <- r'*r */
} else {
ierr = KSP_PCApply(ksp,r,z);CHKERRQ(ierr); /* z <- B r */
ierr = VecNorm(z,NORM_2,&rnorm);CHKERRQ(ierr); /* rnorm <- z'*z */
}
ksp->rnorm = rnorm;
ierr = KSPLogResidualHistory(ksp,rnorm);CHKERRQ(ierr);
ierr = KSPMonitor(ksp,i,rnorm);CHKERRQ(ierr);
}
if (ksp->its >= ksp->max_it) {
if (ksp->normtype != KSP_NORM_NONE) {
ierr = (*ksp->converged)(ksp,i,rnorm,&ksp->reason,ksp->cnvP);CHKERRQ(ierr);
if (!ksp->reason) ksp->reason = KSP_DIVERGED_ITS;
} else {
ksp->reason = KSP_CONVERGED_ITS;
}
}
}
PetscFunctionReturn(0);
}
