[block_gf<T>] Block Green functions
This is a specialisation of gf and views for block functions.
A block Green function is nothing but Green function on a discrete domain representing the block indices, and whose value is itself a Green function.
For convenience, the following aliases are provided
template<typename ... T> using block_gf = gf <block_index, gf<T...>>;
template<typename ... T> using block_gf_view = gf_view <block_index, gf<T...>>;
template<typename ... T> using block_gf_const_view = gf_const_view<block_index, gf<T...>>;
Constructors
The constructors of the gf.
target_shape_t = {}
Factories
Also several factories are provided for these block Green functions.
Factories for the regular type
The factories for the regular type gf are
// From a number and a gf to be copied
template <typename Variable, typename Target, typename Opt>
block_gf<Variable, Target, Opt>
make_block_gf(int n, gf<Variable, Target, Opt> const & g);
// From a vector of gf (moving directly)
template <typename Variable, typename Target, typename Opt>
block_gf<Variable, Target, Opt>
make_block_gf(std::vector<gf<Variable, Target, Opt>> V);
// From a vector of gf or views (a gf must be contructible from GF2)
template <typename Variable, typename Target, typename Opt, typename GF2>
block_gf<Variable, Target, Opt>
make_block_gf(std::vector<GF2> const &V);
// From a init list of GF with the correct type
template <typename Variable, typename Target, typename Opt>
block_gf<Variable, Target, Opt>
make_block_gf(std::initializer_list<gf<Variable, Target, Opt>> const &V);
// From vector<string> and a gf to be copied
template <typename Variable, typename Target, typename Opt>
block_gf<Variable, Target, Opt>
make_block_gf(std::vector<std::string> block_names, gf<Variable, Target, Opt> const &g);
// From vector<string>, vector<gf>
template <typename Variable, typename Target, typename Opt>
block_gf<Variable, Target, Opt>
make_block_gf(std::vector<std::string> block_names, std::vector<gf<Variable, Target, Opt>> V);
// From vector<string>, init_list<GF>
template <typename Variable, typename Target, typename Opt>
block_gf<Variable, Target, Opt>
make_block_gf(std::vector<std::string> block_names,
std::initializer_list<gf<Variable, Target, Opt>> const &V);
Factories for the view type
The factories for the view type gf_view, gf_const_view are
// Build a view of the gf.
// 1- All Green functions must have the same type
// 2- [Expert only] This is a simplified version of the code.
// In the real code, the documentation/manual/triqs is of stripped from G in the type deduction.
template<typename ... G>
gf_view<block_index, G>
make_block_gf_view(G && ... g);
// Make a view from a vector of gf
template<typename GF>
gf_view<block_index,GF>
make_block_gf_view_from_vector (std::vector<GF> V);
Domain & mesh
The domain is a discrete domain …
Singularity
None.
Interpolation method
None.
Data storage
Not exposed to user.
HDF5 storage convention
TO BE WRITTEN.
Iterators
TO BE COMPLETED.
Block gf have a natural iterator, e.g.
// if a BG is block function
for (auto & g: BG) ....
Examples
#include <triqs/gfs.hpp>
#include <triqs/mesh.hpp>
using namespace triqs::gfs;
using namespace triqs;
using nda::clef::placeholder;
int main() {
double beta = 1;
// Make a block gf of 3 gf, which are empty (default constructed).
auto Bg0 = block_gf<imfreq>(3);
auto Bg1 = block_gf<imfreq>({"a", "b", "c"});
std::vector<std::string> block_names = {"a", "b", "c"};
auto Bg11 = block_gf<imfreq>(block_names);
// make a few gf<imfreq> ...
auto g1 = gf<imfreq>({beta, Fermion}, {2, 2});
// ... and construct some block function out of them.
auto Bg2 = make_block_gf<imfreq>(3, g1);
auto Bg3 = make_block_gf<imfreq>({g1, g1, g1});
auto Bg4 = make_block_gf<imfreq>({"a", "b", "c"}, {g1, g1, g1});
// do something on all blocks
for (auto const &g : Bg2) { std::cout << g.mesh() << std::endl; }
// multiply them by 1,2,3 ...
auto i = 1;
for (auto &g : Bg2) g = g * i++;
// a little save in an hdf5 file ?
h5::file file("test_block_gf.h5", 'w');
h5_write(file, "B4", Bg4);
}
Imaginary Freq Mesh with beta = 1, statistic = Fermion, n_iw = 1025, positive_only = false
Imaginary Freq Mesh with beta = 1, statistic = Fermion, n_iw = 1025, positive_only = false
Imaginary Freq Mesh with beta = 1, statistic = Fermion, n_iw = 1025, positive_only = false