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dft_tools/test/triqs/gfs/test_fourier_matsubara.cpp
2013-09-06 17:51:51 +02:00

65 lines
2.3 KiB
C++

//#define TRIQS_ARRAYS_ENFORCE_BOUNDCHECK
#include <triqs/gfs/imfreq.hpp>
#include <triqs/gfs/imtime.hpp>
#include <triqs/gfs/local/fourier_matsubara.hpp>
namespace tql= triqs::clef;
// namespace tqa= triqs::arrays;
// using tqa::range;
using triqs::arrays::make_shape;
using triqs::gfs::Fermion;
using triqs::gfs::imfreq;
using triqs::gfs::imtime;
using triqs::gfs::make_gf;
using triqs::arrays::range;
#define TEST(X) std::cout << BOOST_PP_STRINGIZE((X)) << " ---> "<< (X) <<std::endl<<std::endl;
int main() {
double precision=10e-9;
H5::H5File file("test_fourier_matsubara.h5",H5F_ACC_TRUNC);
triqs::clef::placeholder<0> om_;
double beta =1;
int N=10000;
double E=1;
auto Gw1 = make_gf<imfreq> (beta, Fermion, make_shape(1,1), N);
Gw1(om_) << 1/(om_-E);
// for(auto const& w:Gw1.mesh()){
// std::cout<<"w="<<std::complex<double>(w)<<", Gw1=" << Gw1[w](0,0)<<std::endl;
// }
h5_write(file, "Gw1", Gw1); // the original lorentzian
auto Gt1 = make_gf<imtime> (beta, Fermion, make_shape(1,1), N);
inverse_fourier_impl( Gt1, Gw1, triqs::gfs::matrix_valued() );
// for(auto const& t:Gt1.mesh()){
// std::cout<<"t="<<t<<", expected="<<exp(-E*t) * ( (t>0?-1:0)+1/(1+exp(E*beta)) )<<std::endl;
// }
h5_write(file, "Gt1", Gt1); // the lorentzian TF : lorentzian_inverse
///verification that TF(TF^-1)=Id
auto Gw1b = make_gf<imfreq> (beta, Fermion, make_shape(1,1), N);
fourier_impl(Gw1b, Gt1, triqs::gfs::matrix_valued());
for(auto const& w:Gw1.mesh()){
// std::cout<<"w="<<std::complex<double>(w)<<",Gw1b=" << Gw1b(w)(0,0)<<std::endl;
// std::cout<<"w="<<std::complex<double>(w)<<",Delta Gw1b=" << Gw1b(w)(0,0)-Gw1(w)(0,0)<<std::endl;
if ( std::abs(Gw1b[w](0,0)-Gw1[w](0,0)) > precision) TRIQS_RUNTIME_ERROR<<" fourier_matsubara error : w="<<std::complex<double>(w)<<" ,Gw1b="<<std::abs(Gw1b[w](0,0))<<"\n";
}
h5_write(file,"Gw1b",Gw1b); // must be 0
///verification that the TF is OK
for(auto const & t:Gt1.mesh()){
Gt1[t]-= exp(-E*t) * ( (t>0?-1:0)+1/(1+exp(E*beta)) );
if ( std::abs(Gt1[t](0,0)) > precision) TRIQS_RUNTIME_ERROR<<" fourier_matsubara error : t="<<t<<" ,G1="<<std::abs(Gt1[t](0,0))<<"\n";
}
h5_write(file,"Gt1b",Gt1); // must be 0
///to verify that lazy_fourier computes
auto Gw2 = make_gf<imfreq> (beta, Fermion, make_shape(1,1));
Gw2() = lazy_fourier(Gt1);
}