Boost C++ Libraries

...one of the most highly regarded and expertly designed C++ library projects in the world. — Herb Sutter and Andrei Alexandrescu, C++ Coding Standards

nearest(Geometry const &, std::size_t)

Generate nearest() predicate.

Description

When nearest predicate is passed to the query, k-nearest neighbour search will be performed. nearest() predicate takes a Geometry from which distances to Values are calculated and the maximum number of Values that should be returned. Internally boost::geometry::comparable_distance() is used to perform the calculation.

Synopsis

template<typename Geometry>
unspecified nearest(Geometry const & geometry, std::size_t k)

Parameter(s)

Type	Name	Description
`Geometry const &`	`geometry`	The geometry from which distance is calculated.
`std::size_t`	`k`	The maximum number of values to return.

Example

bgi::query(spatial_index, bgi::nearest(pt, 5), std::back_inserter(result));
bgi::query(spatial_index, bgi::nearest(pt, 5) && bgi::intersects(box), std::back_inserter(result));
bgi::query(spatial_index, bgi::nearest(box, 5), std::back_inserter(result));

	Warning
	Only one `nearest()` predicate may be used in a query.