CGAL::ch_nswe_point

Definition

The function ch_nswe_point finds the four extreme points of a given set of input points using a linear scan of the input points. That is, it determines the points with maximal y, minimal y, minimal x, and maximal x coordinates.

#include <CGAL/ch_selected_extreme_points_2.h>

template <class ForwardIterator>
void
ch_nswe_point ( ForwardIterator first,
ForwardIterator beyond,
ForwardIterator& n,
ForwardIterator& s,
ForwardIterator& w,
ForwardIterator& e,
Traits ch_traits = Default_traits)
traverses the range [first,beyond). After execution, the value of n is an iterator in the range such that *n greater or equal yx *it for all iterators it in the range. Similarly, for s, w, and e the inequalities *s yx *it, *w xy *it, and *e greater or equal xy *it hold for all iterators it in the range.

Requirements

Traits contains the following subset of types from the concept ConvexHullTraits_2 and their corresponding member functions that return instances of these types:

The default traits class Default_traits is the kernel in which the type ForwardIterator::value_type is defined.

See Also

CGAL::ch_e_point
CGAL::ch_n_point
CGAL::ch_ns_point
CGAL::ch_s_point
CGAL::ch_w_point
CGAL::ch_we_point