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