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Cell Neighbor Search
[Combinatoric Algorithms on Grids]

A collection of routines for finding cell neighborhood relationsships and boundary facets. More...

Functions
template<class NBF, class CELLSET, class FACETMAP, class CGT> void	CalculateNeighborCells (NBF &Nb, CELLSET const &cell_set, FACETMAP &facet_map, CGT const &)
	calculate the neighborhood relationship on a set of cells. More...
template<class NBF, class CELLSET, class FACETMAP> void	CalculateNeighborCells (NBF &Nb, CELLSET const &cell_set, FACETMAP &facet_map)
	convenience wrapper for CalculateNeighborCells.
template<class NBF, class CELLSET> void	CalculateNeighborCells (NBF &Nb, CELLSET const &cell_set)
	convenience wrapper for CalculateNeighborCells.

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Detailed Description

A collection of routines for finding cell neighborhood relationsships and boundary facets.

See also:

Combinatoric Algorithms on Grids

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Function Documentation

template<class NBF, class CELLSET, class FACETMAP, class CGT> void CalculateNeighborCells (  NBF &    Nb, CELLSET const &    cell_set, FACETMAP &    facet_map, CGT const &    )

calculate the neighborhood relationship on a set of cells. The algorithm works by inserting new facets into the table and extracting the corresponding counterparts from the table, if they are found. A sample use can be found in test-triang2d-construct.C. Parameters: nbf  [OUT]: A mapping Cell x int -> cell_handle cell_set  [IN]: set of cells on which to calculate neighbors facet_map  [INOUT]: a (possibly empty) mapping from facet vertex sets to FacetOnCellIterators CGT  [TYPE ONLY] a traits type providing iterator types connected to type CELLSET Input facet_map may already contain entries for facets which must have at most one adjacent cell in 'cell_set' . The case that exacly one cell is in 'cell_set' is of course the interesting one and corresponds to facets on the boundary. If cell_set contains all cells of a grid then facet_map should be empty. cell_set contains a subset of the cells of a grid on which the algorithm will be executed. The grid underlying cell_set must have unique vertex sets for facets. The algorithm is incremental in the sense that, given a cell_set C, and a disjoint partition , calling the algorithm n times with instead of yields the same result with the same time and memory complexity. Output nbf: the neighbor relations for cells in cell_set that correspond to internal facets are set in nbf, as well as those corresponding to facets already present in 'facet_map'. facet_map contains all unmatched facets of F(cell_set), that is, facets on the boundary of cell_set that have not been contained in facet_map before. More formally: Let FC = all facets of cell_set I = internal facets of cell_set B = boundary facets of cell_set (i.e. ) FM1 = facets in facet_map before FM2 = facets in facet_map after Then PRECONDITION: POSTCONDITION: Template parameters: NBF nb_type& operator[](CGT::Cell C) where nb_type satisfies: cell_handle& operator[](int nb) Examples: grid_function<CGT::Cell, cell_handle[3]> (for a triangulation, c.NumOfFacets() == 3 cells c) CGT (default: grid_types<CELLSET>) type Cell type CellIterator type FacetOnCellIterator int local (FacetOnCellIterator fc) (get local number n of facet fc, n [0, fc.TheCell().NumOfFacets() [ ) Examples: grid_types<CELLSET> CELLSET type CellIterator CellIterator FirstCell() Examples: Grids, Grid subranges FACETMAP type iterator iterator end() iterator find(vtuple) void erase(iterator) CGT::FacetOnCellIterator& operator[](vtuple) Examples: hash_map<vtuple, CGT::FacetOnCellIterator> Note: vtuple is short for vtuple<CELLSET> Definition at line 51 of file cell-neighbor-search.C.

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Copyright (c) Guntram Berti 1997-2002. See the GrAL Homepage for up-to-date information.

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