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Added laplacian operator for smearing sources

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This commit is contained in:
Guido Cossu
2017-10-04 13:54:54 +01:00
parent d54807b8c0
commit f605230bbb
11 changed files with 757 additions and 200 deletions
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175
lib/qcd/utils/CovariantLaplacian.h
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@ -30,168 +30,57 @@ directory
#ifndef COVARIANT_LAPLACIAN_H
#define COVARIANT_LAPLACIAN_H
namespace Grid {
namespace QCD {
struct LaplacianParams : Serializable {
GRID_SERIALIZABLE_CLASS_MEMBERS(LaplacianParams,
RealD, lo,
RealD, hi,
int, MaxIter,
RealD, tolerance,
int, degree,
int, precision);
// constructor
LaplacianParams(RealD lo = 0.0,
RealD hi = 1.0,
int maxit = 1000,
RealD tol = 1.0e-8,
int degree = 10,
int precision = 64)
: lo(lo),
hi(hi),
MaxIter(maxit),
tolerance(tol),
degree(degree),
precision(precision){};
};
namespace Grid
{
namespace QCD
{
////////////////////////////////////////////////////////////
// Laplacian operator L on adjoint fields
// Laplacian operator L on fermion fields
//
// phi: adjoint field
// L: D_mu^dag D_mu
// phi: fermion field
//
// L phi(x) = Sum_mu [ U_mu(x)phi(x+mu)U_mu(x)^dag +
// U_mu(x-mu)^dag phi(x-mu)U_mu(x-mu)
// -2phi(x)]
// L phi(x) = Sum_mu [ U_mu(x) phi(x+mu) + U_mu(x-mu) phi(x-mu) - 2phi(x)]
//
// Operator designed to be encapsulated by
// an HermitianLinearOperator<.. , ..>
////////////////////////////////////////////////////////////
// has to inherit from a fermion implementation
template <class Impl>
class LaplacianAdjointField: public Metric<typename Impl::Field> {
OperatorFunction<typename Impl::Field> &Solver;
LaplacianParams param;
MultiShiftFunction PowerHalf;
MultiShiftFunction PowerInvHalf;
class Laplacian
{
public:
INHERIT_IMPL_TYPES(Impl);
public:
INHERIT_GIMPL_TYPES(Impl);
// add a bool to smear only in the spatial directions
Laplacian(GridBase *grid, bool spatial = false)
: U(Nd, grid), spatial_laplacian(spatial){};
LaplacianAdjointField(GridBase* grid, OperatorFunction<GaugeField>& S, LaplacianParams& p, const RealD k = 1.0)
: U(Nd, grid), Solver(S), param(p), kappa(k){
AlgRemez remez(param.lo,param.hi,param.precision);
std::cout<<GridLogMessage << "Generating degree "<<param.degree<<" for x^(1/2)"<<std::endl;
remez.generateApprox(param.degree,1,2);
PowerHalf.Init(remez,param.tolerance,false);
PowerInvHalf.Init(remez,param.tolerance,true);
void Mdir(const FermionField &, FermionField &, int, int) { assert(0); }
void Mdiag(const FermionField &, FermionField &) { assert(0); }
};
void Mdir(const GaugeField&, GaugeField&, int, int){ assert(0);}
void Mdiag(const GaugeField&, GaugeField&){ assert(0);}
void ImportGauge(const GaugeField& _U) {
for (int mu = 0; mu < Nd; mu++) {
void ImportGauge(const GaugeField &_U)
{
for (int mu = 0; mu < Nd; mu++)
U[mu] = PeekIndex<LorentzIndex>(_U, mu);
}
}
void M(const GaugeField& in, GaugeField& out) {
// in is an antihermitian matrix
// test
//GaugeField herm = in + adj(in);
//std::cout << "AHermiticity: " << norm2(herm) << std::endl;
void M(const FermionField &in, FermionField &out)
{
int dims = spatial_laplacian ? (Nd - 1) : Nd;
GaugeLinkField tmp(in._grid);
GaugeLinkField tmp2(in._grid);
GaugeLinkField sum(in._grid);
for (int nu = 0; nu < Nd; nu++) {
sum = zero;
GaugeLinkField in_nu = PeekIndex<LorentzIndex>(in, nu);
GaugeLinkField out_nu(out._grid);
for (int mu = 0; mu < Nd; mu++) {
tmp = U[mu] * Cshift(in_nu, mu, +1) * adj(U[mu]);
tmp2 = adj(U[mu]) * in_nu * U[mu];
sum += tmp + Cshift(tmp2, mu, -1) - 2.0 * in_nu;
}
out_nu = (1.0 - kappa) * in_nu - kappa / (double(4 * Nd)) * sum;
PokeIndex<LorentzIndex>(out, out_nu, nu);
}
out = -2.0 * dims * in;
// eventually speed up with the stencil operator, if necessary
for (int mu = 0; mu < dims; mu++)
out += Impl::CovShiftForward(U[mu], mu, in) + Impl::CovShiftBackward(U[mu], mu, in);
}
void MDeriv(const GaugeField& in, GaugeField& der) {
// in is anti-hermitian
RealD factor = -kappa / (double(4 * Nd));
for (int mu = 0; mu < Nd; mu++){
GaugeLinkField der_mu(der._grid);
der_mu = zero;
for (int nu = 0; nu < Nd; nu++){
GaugeLinkField in_nu = PeekIndex<LorentzIndex>(in, nu);
der_mu += U[mu] * Cshift(in_nu, mu, 1) * adj(U[mu]) * in_nu;
}
// the minus sign comes by using the in_nu instead of the
// adjoint in the last multiplication
PokeIndex<LorentzIndex>(der, -2.0 * factor * der_mu, mu);
}
}
// separating this temporarily
void MDeriv(const GaugeField& left, const GaugeField& right,
GaugeField& der) {
// in is anti-hermitian
RealD factor = -kappa / (double(4 * Nd));
for (int mu = 0; mu < Nd; mu++) {
GaugeLinkField der_mu(der._grid);
der_mu = zero;
for (int nu = 0; nu < Nd; nu++) {
GaugeLinkField left_nu = PeekIndex<LorentzIndex>(left, nu);
GaugeLinkField right_nu = PeekIndex<LorentzIndex>(right, nu);
der_mu += U[mu] * Cshift(left_nu, mu, 1) * adj(U[mu]) * right_nu;
der_mu += U[mu] * Cshift(right_nu, mu, 1) * adj(U[mu]) * left_nu;
}
PokeIndex<LorentzIndex>(der, -factor * der_mu, mu);
}
}
void Minv(const GaugeField& in, GaugeField& inverted){
HermitianLinearOperator<LaplacianAdjointField<Impl>,GaugeField> HermOp(*this);
Solver(HermOp, in, inverted);
}
void MSquareRoot(GaugeField& P){
GaugeField Gp(P._grid);
HermitianLinearOperator<LaplacianAdjointField<Impl>,GaugeField> HermOp(*this);
ConjugateGradientMultiShift<GaugeField> msCG(param.MaxIter,PowerHalf);
msCG(HermOp,P,Gp);
P = Gp;
}
void MInvSquareRoot(GaugeField& P){
GaugeField Gp(P._grid);
HermitianLinearOperator<LaplacianAdjointField<Impl>,GaugeField> HermOp(*this);
ConjugateGradientMultiShift<GaugeField> msCG(param.MaxIter,PowerInvHalf);
msCG(HermOp,P,Gp);
P = Gp;
}
private:
RealD kappa;
private:
bool spatial_laplacian;
std::vector<GaugeLinkField> U;
};
}
}
}; // Laplacian
} // QCD
} // Grid
#endif