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Lots more setup options, still working on them

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This commit is contained in:
Peter Boyle 2023-11-15 17:58:04 -05:00
parent e0543e8af5
commit a3ca71ec01
1 changed files with 119 additions and 0 deletions
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119
Grid/algorithms/multigrid/Aggregates.h
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@ -32,6 +32,13 @@ Author: paboyle <paboyle@ph.ed.ac.uk>
NAMESPACE_BEGIN(Grid);
inline RealD AggregatePowerLaw(RealD x)
{
// return std::pow(x,-4);
// return std::pow(x,-3);
return std::pow(x,-5);
}
template<class Fobj,class CComplex,int nbasis>
class Aggregation {
public:
@ -246,9 +253,54 @@ public:
// Initial matrix element
hermop.Op(noise,Mn);
if(b==0) std::cout<<GridLogMessage << "noise <n|MdagM|n> "<<norm2(Mn)<<std::endl;
// Filter
Chebyshev<FineField> Cheb(lo,hi,orderfilter);
Cheb(hermop,noise,Mn);
scale = std::pow(norm2(Mn),-0.5); Mn=Mn*scale;
// Refine
Chebyshev<FineField> PowerLaw(lo,hi,1000,AggregatePowerLaw);
noise = Mn;
PowerLaw(hermop,noise,Mn);
scale = std::pow(norm2(Mn),-0.5); Mn=Mn*scale;
// normalise
subspace[b] = Mn;
hermop.Op(Mn,tmp);
std::cout<<GridLogMessage << "filt ["<<b<<"] <n|MdagM|n> "<<norm2(tmp)<<std::endl;
}
}
virtual void CreateSubspaceChebyshevPowerLaw(GridParallelRNG &RNG,LinearOperatorBase<FineField> &hermop,
int nn,
double hi,
int orderfilter
) {
RealD scale;
FineField noise(FineGrid);
FineField Mn(FineGrid);
FineField tmp(FineGrid);
// New normalised noise
std::cout << GridLogMessage<<" Chebyshev subspace pure noise : ord "<<orderfilter<<" [0,"<<hi<<"]"<<std::endl;
std::cout << GridLogMessage<<" Chebyshev subspace pure noise : nbasis "<<nn<<std::endl;
for(int b =0;b<nbasis;b++)
{
gaussian(RNG,noise);
scale = std::pow(norm2(noise),-0.5);
noise=noise*scale;
// Initial matrix element
hermop.Op(noise,Mn);
if(b==0) std::cout<<GridLogMessage << "noise <n|MdagM|n> "<<norm2(Mn)<<std::endl;
// Filter
Chebyshev<FineField> Cheb(0.0,hi,orderfilter,AggregatePowerLaw);
Cheb(hermop,noise,Mn);
// normalise
scale = std::pow(norm2(Mn),-0.5); Mn=Mn*scale;
subspace[b] = Mn;
@ -258,5 +310,72 @@ public:
}
virtual void CreateSubspaceMultishift(GridParallelRNG &RNG,LinearOperatorBase<FineField> &hermop,
double Lo,double tol,int maxit)
{
RealD scale;
FineField noise(FineGrid);
FineField Mn(FineGrid);
FineField tmp(FineGrid);
// New normalised noise
std::cout << GridLogMessage<<" Multishift subspace : Lo "<<Lo<<std::endl;
// Filter
// [ 1/6(x+Lo) - 1/2(x+2Lo) + 1/2(x+3Lo) -1/6(x+4Lo) = Lo^3 /[ (x+1Lo)(x+2Lo)(x+3Lo)(x+4Lo) ]
//
// 1/(x+Lo) - 1/(x+2 Lo)
double epsilon = Lo/3;
std::vector<RealD> alpha({1.0/6.0,-1.0/2.0,1.0/2.0,-1.0/6.0});
std::vector<RealD> shifts({Lo,Lo+epsilon,Lo+2*epsilon,Lo+3*epsilon});
std::vector<RealD> tols({tol,tol,tol,tol});
std::cout << "sizes "<<alpha.size()<<" "<<shifts.size()<<" "<<tols.size()<<std::endl;
MultiShiftFunction msf(4,0.0,95.0);
std::cout << "msf constructed "<<std::endl;
msf.poles=shifts;
msf.residues=alpha;
msf.tolerances=tols;
msf.norm=0.0;
msf.order=alpha.size();
ConjugateGradientMultiShift<FineField> MSCG(maxit,msf);
for(int b =0;b<nbasis;b++)
{
gaussian(RNG,noise);
scale = std::pow(norm2(noise),-0.5);
noise=noise*scale;
// Initial matrix element
hermop.Op(noise,Mn);
if(b==0) std::cout<<GridLogMessage << "noise <n|MdagM|n> "<<norm2(Mn)<<std::endl;
MSCG(hermop,noise,Mn);
scale = std::pow(norm2(Mn),-0.5); Mn=Mn*scale;
subspace[b] = Mn;
hermop.Op(Mn,tmp);
std::cout<<GridLogMessage << "filt ["<<b<<"] <n|MdagM|n> "<<norm2(tmp)<<std::endl;
}
}
virtual void RefineSubspace(LinearOperatorBase<FineField> &hermop,
double Lo,double tol,int maxit)
{
FineField tmp(FineGrid);
for(int b =0;b<nbasis;b++)
{
RealD MirsShift = Lo;
ConjugateGradient<FineField> CGsloppy(tol,maxit,false);
ShiftedHermOpLinearOperator<FineField> ShiftedFineHermOp(hermop,MirsShift);
CGsloppy(hermop,subspace[b],tmp);
subspace[b]=tmp;
}
}
};
NAMESPACE_END(Grid);