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dft_tools/doc/reference/c++/gf/gf_subscript.rst

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2013-09-18 15:13:23 +02:00
.. highlight:: c
.. _gf_subscript:
Operator []
==================================
**Synopsis** ::
value_type const & operator[](mesh_t::index_t const &) const (1a)
value_type & operator[](mesh_t::index_t const &) (1b)
value_type const & operator[](closest_mesh_pt_t const &) const (2a)
value_type & operator[](closest_mesh_pt_t const &) (2b)
ClefExpression operator[](ClefExpression expr) const (3)
The operator [] is in charge of accessing the data of the Green function
on the mesh. This is therefore a way to modify the Green function.
NB : This is valid for both the container (e.g. gf), and the view (e.g. gf_view).
.. _gf_subscript_index:
(1) Use the linear index of the mesh
-----------------------------------------
.. _gf_subscript_closest:
..
(2) Find the closest mesh point from a domain point
---------------------------------------------------------
* May or may not be provided by the specialisation. Cf specialization.
* This is normally used with the helper function::
closest_mesh_point_t closest_mesh_point(Anything x)
closest_mesh_point_t is just a little "vehicle" that can contain anything (by copy or ref ???),
and carry it through the [].
* Usage ::
g [ closest_mesh_point(x) ] += y;
.. _gf_subscript_lazy:
(3) Interaction with clef expressions
-------------------------------------------------
Like (), [] can be called with a ClefExpression.