triqs::gfs::gf_expr< Tag, L, R >

#include <triqs/gfs/gf/gf_expr.hpp>

Detailed Description

template<typename Tag, typename L, typename R>
struct triqs::gfs::gf_expr< Tag, L, R >

Lazy expression node representing a binary operation between two Green's function operands.

Models the GreenFunction concept, so expressions can be nested and assigned to a triqs::gfs::gf. The mesh and target are deduced from the operands and the operation is evaluated lazily, element by element, on access.

Template Parameters

Tag	Operation tag (+, -, *, /).
L	Type of the left operand (a Green's function or a wrapped scalar).
R	Type of the right operand (a Green's function or a wrapped scalar).

Definition at line 172 of file gf_expr.hpp.

Public Types
using	L_t = std::remove_reference_t<L>
	Decayed type of the left operand.
using	mesh_t = typename gfs_expr_tools::_or_<typename L_t::mesh_t, typename R_t::mesh_t>::type
	Mesh type of the expression, deduced from the two operands.
using	R_t = std::remove_reference_t<R>
	Decayed type of the right operand.
using	regular_t = gf<mesh_t, target_t>
	Regular (owning) type the expression evaluates to.
using	target_t = typename gfs_expr_tools::_or_<typename L_t::target_t, typename R_t::target_t>::type
	Target type of the expression, deduced from the two operands.

Public Member Functions
template<typename LL, typename RR>
	gf_expr (LL &&l_, RR &&r_)
	Construct from the two operands.
auto	data_shape () const
	Get the data shape of the expression.
auto const &	mesh () const
	Get the mesh of the expression (computed lazily and cached).
template<typename... Args>
decltype(auto)	operator() (Args &&...1) const
	Evaluate the expression via call at the given arguments (one per mesh dimension).
template<typename... Keys>
decltype(auto)	operator[] (Keys &&...keys) const
	Evaluate the expression via subscript at the given keys.

Public Attributes
L	l
	Left operand.
R	r
	Right operand.

Friends
std::ostream &	operator<< (std::ostream &sout, gf_expr const &expr)
	Stream output of the expression.

Constructor & Destructor Documentation

gf_expr()

template<typename Tag, typename L, typename R>

template<typename LL, typename RR>

triqs::gfs::gf_expr< Tag, L, R >::gf_expr ( LL && l_, RR && r_ )

inline

Construct from the two operands.

Template Parameters

LL	Forwarding type of the left operand.
RR	Forwarding type of the right operand.

Parameters

l_	Left operand.
r_	Right operand.

Definition at line 205 of file gf_expr.hpp.

Member Function Documentation

data_shape()

template<typename Tag, typename L, typename R>

auto triqs::gfs::gf_expr< Tag, L, R >::data_shape ( ) const

inline

Get the data shape of the expression.

Returns

The combined data shape of the two operands.

Definition at line 224 of file gf_expr.hpp.

mesh()

template<typename Tag, typename L, typename R>

auto const & triqs::gfs::gf_expr< Tag, L, R >::mesh ( ) const

inline

Get the mesh of the expression (computed lazily and cached).

Returns

A const reference to the combined mesh.

Definition at line 215 of file gf_expr.hpp.

operator()()

template<typename Tag, typename L, typename R>

template<typename... Args>

decltype(auto) triqs::gfs::gf_expr< Tag, L, R >::operator() ( Args &&... 1 ) const

inline

Evaluate the expression via call at the given arguments (one per mesh dimension).

Template Parameters

Args	Types of the evaluation arguments.

Returns

The result of applying the operation to the operands' evaluated values.

Definition at line 243 of file gf_expr.hpp.

operator[]()

template<typename Tag, typename L, typename R>

template<typename... Keys>

decltype(auto) triqs::gfs::gf_expr< Tag, L, R >::operator[] ( Keys &&... keys ) const

inline

Evaluate the expression via subscript at the given keys.

Template Parameters

Keys	Types of the access keys.

Parameters

keys	Mesh points/indices.

Returns

The result of applying the operation to the operands' subscripted values.

Definition at line 233 of file gf_expr.hpp.

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The documentation for this struct was generated from the following files:

• triqs/gfs/gf/gf.hpp
• triqs/gfs/gf/gf_expr.hpp