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dft_tools/test/triqs/gfs/test_fourier_matsubara.cpp
Olivier Parcollet 579368f24b gf. Clean Fourier
- lazy_fourier and co --> fourier
- ex fourier --> make_gf_from_fourier to make a new gf
- = fourier (g) works only iif lhs is a view, like scalar.
- updated python (commented fourier method).
2013-10-23 18:46:55 +02:00

63 lines
2.5 KiB
C++

#define TRIQS_ARRAYS_ENFORCE_BOUNDCHECK
#include <triqs/gfs.hpp>
using namespace triqs::gfs;
using namespace triqs::arrays;
#define TEST(X) std::cout << BOOST_PP_STRINGIZE((X)) << " ---> "<< (X) <<std::endl<<std::endl;
#include <triqs/gfs/local/fourier_matsubara.hpp>
namespace triqs { namespace gfs {
// defined in the cpp file
void fourier_impl (gf_view<imfreq,scalar_valued> gw , gf_const_view<imtime,scalar_valued> gt, scalar_valued);
void fourier_impl (gf_view<imfreq,matrix_valued> gw , gf_const_view<imtime,matrix_valued> gt, matrix_valued);
void inverse_fourier_impl (gf_view<imtime,scalar_valued> gt, gf_const_view<imfreq,scalar_valued> gw, scalar_valued);
void inverse_fourier_impl (gf_view<imtime,matrix_valued> gt, gf_const_view<imfreq,matrix_valued> gw, matrix_valued);
}}
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 = gf<imfreq> {{beta, Fermion, N}, {1,1}};
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 = gf<imtime> {{beta, Fermion, N}, {1,1}};
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 = gf<imfreq> {{beta, Fermion, N}, {1,1}};
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 fourier computes
auto Gw2 = gf<imfreq> {{beta, Fermion}, {1,1}};
Gw2() = fourier(Gt1);
}