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dft_tools/triqs/gfs/imtime.hpp
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

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3.9 KiB
C++

/*******************************************************************************
*
* TRIQS: a Toolbox for Research in Interacting Quantum Systems
*
* Copyright (C) 2012 by M. Ferrero, O. Parcollet
*
* TRIQS is free software: you can redistribute it and/or modify it under the
* terms of the GNU General Public License as published by the Free Software
* Foundation, either version 3 of the License, or (at your option) any later
* version.
*
* TRIQS is distributed in the hope that it will be useful, but WITHOUT ANY
* WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
* FOR A PARTICULAR PURPOSE. See the GNU General Public License for more
* details.
*
* You should have received a copy of the GNU General Public License along with
* TRIQS. If not, see <http://www.gnu.org/licenses/>.
*
******************************************************************************/
#ifndef TRIQS_GF_MATSUBARA_TIME_H
#define TRIQS_GF_MATSUBARA_TIME_H
#include "./tools.hpp"
#include "./gf.hpp"
#include "./local/tail.hpp"
#include "./local/no_tail.hpp"
#include "./domains/matsubara.hpp"
#include "./meshes/linear.hpp"
#include "./evaluators.hpp"
namespace triqs { namespace gfs {
struct imtime {};
// gf_mesh type and its factories
template <typename Opt> struct gf_mesh<imtime, Opt> : linear_mesh<matsubara_domain<false>> {
typedef linear_mesh<matsubara_domain<false>> B;
gf_mesh() = default;
gf_mesh(B const &x) : B(x) {} // enables also construction from another Opt
gf_mesh(typename B::domain_t d, int n_time_slices, mesh_kind mk = half_bins) : B(d, 0, d.beta, n_time_slices, mk) {}
gf_mesh(double beta, statistic_enum S, int n_time_slices, mesh_kind mk = half_bins) : gf_mesh({beta, S}, n_time_slices, mk) {}
};
namespace gfs_implementation {
// singularity. If no_tail is given, then it is the default (nothing)
template<> struct singularity<imtime,matrix_valued,void> { typedef local::tail type;};
template<> struct singularity<imtime,scalar_valued,void> { typedef local::tail type;};
// h5 name
template<typename Opt> struct h5_name<imtime,matrix_valued,Opt> { static std::string invoke(){ return "ImTime";}};
/// --------------------------- data access ---------------------------------
template<typename Opt> struct data_proxy<imtime,matrix_valued,Opt> : data_proxy_array<double,3> {};
template<typename Opt> struct data_proxy<imtime,scalar_valued,Opt> : data_proxy_array<double,1> {};
/// --------------------------- closest mesh point on the grid ---------------------------------
template<typename Opt, typename Target>
struct get_closest_point <imtime,Target,Opt> {
// index_t is int
template<typename G, typename T>
static int invoke(G const * g, closest_pt_wrap<T> const & p) {
double x = (g->mesh().kind()==half_bins ? double(p.value) : double(p.value)+ 0.5*g->mesh().delta());
int n = std::floor(x/g->mesh().delta());
return n;
}
};
/// --------------------------- evaluator ---------------------------------
// this one is specific because of the beta-antiperiodicity for fermions
template<>
struct evaluator_fnt_on_mesh<imtime> {
double w1, w2; long n;
evaluator_fnt_on_mesh() = default;
evaluator_fnt_on_mesh (gf_mesh<imtime> const & m, double tau) {
double beta = m.domain().beta;
int p = std::floor(tau/beta);
tau -= p*beta;
double w; bool in;
std::tie(in, n, w) = windowing(m,tau);
if (!in) TRIQS_RUNTIME_ERROR <<" Evaluation out of bounds";
if ((m.domain().statistic == Fermion) && (p%2==1)) {w2 = -w; w1 = w-1;} else { w2 = w; w1 = 1-w;}
}
template<typename F> auto operator()(F const & f) const DECL_AND_RETURN(w1 * f(n) + w2 * f (n+1));
};
// now evaluator
template<typename Opt, typename Target> struct evaluator<imtime,Target,Opt> : evaluator_one_var<imtime>{};
} // gfs_implementation.
}}
#endif