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Grid/tests/Test_gp_rect_force.cc
paboyle 5a80930dd2 Charge conjugation boundary conditions for gauge fields implemented as a policy
class, changing the nature of covariant Cshifts used in
plaquettes, rectangles and staples.

As a result same code is used for the plaq and rect action independent of the BC type.

Should probably isolate the BC in a separate class that Gimpl takes as a template param.
Do the same with smearing policies.

This would then allow composition of BC with smearing etc....
2016-01-02 13:37:25 +00:00

99 lines
2.6 KiB
C++

#include <Grid.h>
using namespace std;
using namespace Grid;
using namespace Grid::QCD;
#define parallel_for PARALLEL_FOR_LOOP for
int main (int argc, char ** argv)
{
Grid_init(&argc,&argv);
std::vector<int> latt_size = GridDefaultLatt();
std::vector<int> simd_layout = GridDefaultSimd(Nd,vComplex::Nsimd());
std::vector<int> mpi_layout = GridDefaultMpi();
GridCartesian Grid(latt_size,simd_layout,mpi_layout);
GridRedBlackCartesian RBGrid(latt_size,simd_layout,mpi_layout);
int threads = GridThread::GetThreads();
std::cout<<GridLogMessage << "Grid is setup to use "<<threads<<" threads"<<std::endl;
std::vector<int> seeds({1,2,3,4});
GridParallelRNG pRNG(&Grid);
pRNG.SeedRandomDevice();
LatticeGaugeField U(&Grid);
SU3::HotConfiguration(pRNG,U);
double beta = 1.0;
double c1 = 0.331;
//GparityPlaqPlusRectangleActionR Action(beta,c1);
ConjugateWilsonGaugeActionR Action(beta);
//WilsonGaugeActionR Action(beta);
ComplexD S = Action.S(U);
// get the deriv of phidag MdagM phi with respect to "U"
LatticeGaugeField UdSdU(&Grid);
Action.deriv(U,UdSdU);
////////////////////////////////////
// Modify the gauge field a little
////////////////////////////////////
RealD dt = 0.0001;
LatticeColourMatrix mommu(&Grid);
LatticeColourMatrix forcemu(&Grid);
LatticeGaugeField mom(&Grid);
LatticeGaugeField Uprime(&Grid);
for(int mu=0;mu<Nd;mu++){
SU3::GaussianLieAlgebraMatrix(pRNG, mommu); // Traceless antihermitian momentum; gaussian in lie alg
PokeIndex<LorentzIndex>(mom,mommu,mu);
// fourth order exponential approx
parallel_for(auto i=mom.begin();i<mom.end();i++){ // exp(pmu dt) * Umu
Uprime[i](mu) = U[i](mu) + mom[i](mu)*U[i](mu)*dt ;
}
}
ComplexD Sprime = Action.S(Uprime);
//////////////////////////////////////////////
// Use derivative to estimate dS
//////////////////////////////////////////////
LatticeComplex dS(&Grid); dS = zero;
for(int mu=0;mu<Nd;mu++){
auto UdSdUmu = PeekIndex<LorentzIndex>(UdSdU,mu);
mommu = PeekIndex<LorentzIndex>(mom,mu);
// Update gauge action density
// U = exp(p dt) U
// dU/dt = p U
// so dSdt = trace( dUdt dSdU) = trace( p UdSdUmu )
dS = dS - trace(mommu*UdSdUmu)*dt*2.0;
}
Complex dSpred = sum(dS);
std::cout << GridLogMessage << " S "<<S<<std::endl;
std::cout << GridLogMessage << " Sprime "<<Sprime<<std::endl;
std::cout << GridLogMessage << "dS "<<Sprime-S<<std::endl;
std::cout << GridLogMessage << "pred dS "<< dSpred <<std::endl;
std::cout<< GridLogMessage << "Done" <<std::endl;
Grid_finalize();
}