dust3d/thirdparty/cgal/CGAL-4.13/include/CGAL/Min_annulus_d.h

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// Copyright (c) 1997-2001 ETH Zurich (Switzerland).
// All rights reserved.
//
// This file is part of CGAL (www.cgal.org).
// You can redistribute it and/or modify it under the terms of the GNU
// General Public License as published by the Free Software Foundation,
// either version 3 of the License, or (at your option) any later version.
//
// Licensees holding a valid commercial license may use this file in
// accordance with the commercial license agreement provided with the software.
//
// This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
// WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
//
// $URL$
// $Id$
// SPDX-License-Identifier: GPL-3.0+
//
//
// Author(s) : Sven Schoenherr <sven@inf.ethz.ch>
#ifndef CGAL_MIN_ANNULUS_D_H
#define CGAL_MIN_ANNULUS_D_H
#include <CGAL/license/Bounding_volumes.h>
#ifdef _MSC_VER
# pragma warning(push)
# pragma warning(disable: 4244) // conversion warning in Boost iterator_adaptor
#endif
// includes
// --------
#include <CGAL/Optimisation/basic.h>
#include <CGAL/function_objects.h>
#include <CGAL/QP_options.h>
#include <CGAL/QP_solver/QP_solver.h>
#include <CGAL/QP_solver/functors.h>
#include <CGAL/QP_solver/QP_full_filtered_pricing.h>
#include <CGAL/QP_solver/QP_full_exact_pricing.h>
#include <CGAL/boost/iterator/counting_iterator.hpp>
#include <CGAL/boost/iterator/transform_iterator.hpp>
#include <boost/functional.hpp>
// here is how it works. We have d+2 variables:
// R (big radius), r (small radius), c (center). The problem is
//
// min R^2 - r^2
// s.t. ||p - c||^2 >= r^2 for all p
// ||p - c||^2 <= R^2 for all p
//
// This looks nonlinear, but we can in fact make the substitutions
// u = R^2 - c^Tc, v = r^2 - c^Tc and get the following equivalent
// linear program:
//
// min u - v
// s.t. p^Tp - 2p^Tc >= v for all p
// p^Tp - 2p^Tc <= u for all p
//
// or
//
// max v - u
// s.t. v + 2p_1c_1 + 2p_2c_2 + ... + 2p_dc_d <= p^Tp for all p
// - u - 2p_1c_1 - 2p_2c_2 - ... - 2p_dc_d <= -p^Tp for all p
//
// When we introduce a dual variable x_p for every constraint in the first
// set and a dual variable y_p for every constraint in the second set,
// we obtain the following dual program:
//
// min \sum_p x_p p^Tp - \sum_p y_p p^Tp
// s.t.
// 2\sum_p x_p p - 2\sum_p y_p p = 0
// \sum_p x_p = 1 (constraint for v)
// - \sum_p y_p = -1 (constraint for u)
// x_p >= 0 for all p
// y_p >= 0 for all p
//
// in the following functors, the ordering of the constraints is as above;
// the indices of the variables are: x_p_j <-> 2 * j, y_p_j <-> 2 * j + 1
// we also make the substitutions x'_p = x_p / h_p^2, y'_p = y_p / h_p^2
// where h_p is the homogenizing coordinate of p, in order to allow
// homogeneous points. This, however, means that the computed annulus is
// not necessarily correct. If P is a set of homogeneous points,
// P = { (p_0,...,p_{d-1}, h_p) },
// then we always get a *feasible* annulus for the point set
// P' = { (p_0*h_p,...,p_{d-1}*h_p, h_p*h_p) }.
// If the type NT is inexact, this annulus might not even be optimal, since
// the objective function involves terms p^Tp that might not be exactly
// computed -> document all this!!!
namespace CGAL {
namespace MA_detail {
// functor for a fixed column of A
template <class NT, class Iterator>
class A_column : public CGAL::cpp98::unary_function <int, NT>
{
public:
typedef NT result_type;
A_column()
{}
A_column (int j, int d, Iterator it)
: j_ (j), d_ (d), it_ (it), h_p (*(it+d)), nt_0_ (0), nt_2_ (2)
{}
result_type operator() (int i) const
{
if (j_ % 2 == 0) {
// column for x_p
if (i < d_) return *(it_ + i) * h_p * nt_2_;
if (i == d_) return h_p * h_p;
return nt_0_;
} else {
// column for y_p
if (i < d_) return -(*(it_ + i)) * h_p * nt_2_;
if (i == d_+1) return -h_p * h_p;
return nt_0_;
}
}
private:
int j_; // column number
int d_; // dimension
Iterator it_; // the iterator through the column's point
NT h_p; // the homogenizing coordinate of p
NT nt_0_;
NT nt_2_;
};
// functor for matrix A
template <class NT, class Access_coordinate_begin_d,
class Point_iterator >
class A_matrix : public CGAL::cpp98::unary_function
<int, boost::transform_iterator <A_column
<NT, typename Access_coordinate_begin_d::Coordinate_iterator>,
boost::counting_iterator<int> > >
{
typedef typename MA_detail::A_column
<NT, typename Access_coordinate_begin_d::Coordinate_iterator> A_column;
public:
typedef boost::transform_iterator
<A_column, boost::counting_iterator<int> > result_type;
A_matrix ()
{}
A_matrix (int d,
const Access_coordinate_begin_d& da_coord,
Point_iterator P)
: d_ (d), da_coord_ (da_coord), P_ (P)
{}
result_type operator () (int j) const
{
return result_type
(0, A_column (j, d_, da_coord_ (*(P_+j/2))));
}
private:
int d_; // dimension
Access_coordinate_begin_d da_coord_; // data accessor
Point_iterator P_; // point set P
};
// The functor necessary to realize access to b
template <class NT>
class B_vector : public CGAL::cpp98::unary_function<int, NT>
{
public:
typedef NT result_type;
B_vector()
{}
B_vector (int d)
: d_ (d), nt_0_ (0), nt_1_ (1)
{}
result_type operator() (int i) const
{
if (i == d_) return nt_1_;
if (i == d_+1) return -nt_1_;
return nt_0_;
}
private:
int d_;
NT nt_0_;
NT nt_1_;
};
}
// Class interfaces
// ================
template < class Traits_ >
class Min_annulus_d {
public:
// self
typedef Traits_ Traits;
typedef Min_annulus_d<Traits> Self;
// types from the traits class
typedef typename Traits::Point_d Point;
typedef typename Traits::Rep_tag Rep_tag;
typedef typename Traits::RT RT;
typedef typename Traits::FT FT;
typedef typename Traits::Access_dimension_d
Access_dimension_d;
typedef typename Traits::Access_coordinates_begin_d
Access_coordinates_begin_d;
typedef typename Traits::Construct_point_d
Construct_point_d;
typedef typename Traits::ET ET;
typedef typename Traits::NT NT;
// public types
typedef std::vector<Point> Point_vector;
typedef typename Point_vector::const_iterator
Point_iterator;
private:
// QP solver iterator types
typedef MA_detail::A_matrix <NT, Access_coordinates_begin_d,
Point_iterator> A_matrix;
typedef boost::transform_iterator
<A_matrix,
boost::counting_iterator<int> > A_iterator;
typedef MA_detail::B_vector <NT> B_vector;
typedef boost::transform_iterator
<B_vector,
boost::counting_iterator<int> > B_iterator;
typedef CGAL::Const_oneset_iterator<CGAL::Comparison_result> R_iterator;
typedef std::vector<NT> C_vector;
typedef typename C_vector::const_iterator C_iterator;
// Program type
typedef CGAL::Nonnegative_linear_program_from_iterators
<A_iterator, B_iterator, R_iterator, C_iterator> LP;
// Tags
typedef QP_solver_impl::QP_tags <Tag_true, Tag_true> QP_tags;
// Solver types
typedef CGAL::QP_solver <LP, ET, QP_tags > Solver;
typedef typename Solver::Pricing_strategy Pricing_strategy;
// types from the QP solver
typedef typename Solver::Basic_variable_index_iterator
Basic_variable_index_iterator;
// private types
typedef std::vector<ET> ET_vector;
typedef QP_access_by_index
<typename std::vector<Point>::const_iterator, int> Point_by_index;
typedef boost::binder2nd< std::divides<int> >
Divide;
typedef std::vector<int> Index_vector;
typedef std::vector<NT> NT_vector;
typedef std::vector<NT_vector> NT_matrix;
public:
// public types
typedef CGAL::Join_input_iterator_1<
Basic_variable_index_iterator,
CGAL::Unary_compose_1<Point_by_index,Divide> >
Support_point_iterator;
typedef typename Index_vector::const_iterator IVCI;
typedef CGAL::Join_input_iterator_1<
IVCI, Point_by_index >
Inner_support_point_iterator;
typedef CGAL::Join_input_iterator_1<
IVCI, Point_by_index >
Outer_support_point_iterator;
typedef IVCI Inner_support_point_index_iterator;
typedef IVCI Outer_support_point_index_iterator;
typedef typename ET_vector::const_iterator
Coordinate_iterator;
// creation
Min_annulus_d( const Traits& traits = Traits())
: tco( traits), da_coord(tco.access_coordinates_begin_d_object()),
d( -1), solver(0){}
template < class InputIterator >
Min_annulus_d( InputIterator first,
InputIterator last,
const Traits& traits = Traits())
: tco( traits), da_coord(tco.access_coordinates_begin_d_object()),
solver(0) {
set( first, last);
}
~Min_annulus_d() {
if (solver)
delete solver;
}
// access to point set
int ambient_dimension( ) const { return d; }
int number_of_points( ) const { return static_cast<int>(points.size()); }
Point_iterator points_begin( ) const { return points.begin(); }
Point_iterator points_end ( ) const { return points.end (); }
// access to support points
int
number_of_support_points( ) const
{ return number_of_points() < 2 ?
number_of_points() :
solver->number_of_basic_variables(); }
Support_point_iterator
support_points_begin() const {
CGAL_optimisation_assertion_msg(number_of_points() >= 2,
"support_points_begin: not enough points");
return Support_point_iterator(
solver->basic_original_variable_indices_begin(),
CGAL::compose1_1(
Point_by_index( points.begin()),
boost::bind2nd( std::divides<int>(), 2)));
}
Support_point_iterator
support_points_end() const {
CGAL_optimisation_assertion_msg(number_of_points() >= 2,
"support_points_begin: not enough points");
return Support_point_iterator(
solver->basic_original_variable_indices_end(),
CGAL::compose1_1(
Point_by_index( points.begin()),
boost::bind2nd( std::divides<int>(), 2)));
}
int number_of_inner_support_points() const { return static_cast<int>(inner_indices.size());}
int number_of_outer_support_points() const { return static_cast<int>(outer_indices.size());}
Inner_support_point_iterator
inner_support_points_begin() const
{ return Inner_support_point_iterator(
inner_indices.begin(),
Point_by_index( points.begin())); }
Inner_support_point_iterator
inner_support_points_end() const
{ return Inner_support_point_iterator(
inner_indices.end(),
Point_by_index( points.begin())); }
Outer_support_point_iterator
outer_support_points_begin() const
{ return Outer_support_point_iterator(
outer_indices.begin(),
Point_by_index( points.begin())); }
Outer_support_point_iterator
outer_support_points_end() const
{ return Outer_support_point_iterator(
outer_indices.end(),
Point_by_index( points.begin())); }
Inner_support_point_index_iterator
inner_support_points_indices_begin() const
{ return inner_indices.begin(); }
Inner_support_point_index_iterator
inner_support_points_indices_end() const
{ return inner_indices.end(); }
Outer_support_point_index_iterator
outer_support_points_indices_begin() const
{ return outer_indices.begin(); }
Outer_support_point_index_iterator
outer_support_points_indices_end() const
{ return outer_indices.end(); }
// access to center (rational representation)
Coordinate_iterator
center_coordinates_begin( ) const { return center_coords.begin(); }
Coordinate_iterator
center_coordinates_end ( ) const { return center_coords.end (); }
// access to squared radii (rational representation)
ET squared_inner_radius_numerator( ) const { return sqr_i_rad_numer; }
ET squared_outer_radius_numerator( ) const { return sqr_o_rad_numer; }
ET squared_radii_denominator ( ) const { return sqr_rad_denom; }
// access to center and squared radii
// NOTE: an implicit conversion from ET to RT must be available!
Point
center( ) const
{ CGAL_optimisation_precondition( ! is_empty());
return tco.construct_point_d_object()( ambient_dimension(),
center_coordinates_begin(),
center_coordinates_end()); }
FT
squared_inner_radius( ) const
{ CGAL_optimisation_precondition( ! is_empty());
return FT( squared_inner_radius_numerator()) /
FT( squared_radii_denominator()); }
FT
squared_outer_radius( ) const
{ CGAL_optimisation_precondition( ! is_empty());
return FT( squared_outer_radius_numerator()) /
FT( squared_radii_denominator()); }
// predicates
CGAL::Bounded_side
bounded_side( const Point& p) const
{ CGAL_optimisation_precondition(
is_empty() || tco.access_dimension_d_object()( p) == d);
ET sqr_d = sqr_dist( p);
ET h_p_sqr = da_coord(p)[d] * da_coord(p)[d];
return CGAL::Bounded_side
(CGAL_NTS sign( sqr_d - h_p_sqr * sqr_i_rad_numer)
* CGAL_NTS sign( h_p_sqr * sqr_o_rad_numer - sqr_d)); }
bool
has_on_bounded_side( const Point& p) const
{ CGAL_optimisation_precondition(
is_empty() || tco.access_dimension_d_object()( p) == d);
ET sqr_d = sqr_dist( p);
ET h_p_sqr = da_coord(p)[d] * da_coord(p)[d];
return ( ( h_p_sqr * sqr_i_rad_numer < sqr_d) &&
( sqr_d < h_p_sqr * sqr_o_rad_numer)); }
bool
has_on_boundary( const Point& p) const
{ CGAL_optimisation_precondition(
is_empty() || tco.access_dimension_d_object()( p) == d);
ET sqr_d = sqr_dist( p);
ET h_p_sqr = da_coord(p)[d] * da_coord(p)[d];
return (( sqr_d == h_p_sqr * sqr_i_rad_numer) ||
( sqr_d == h_p_sqr * sqr_o_rad_numer));}
bool
has_on_unbounded_side( const Point& p) const
{ CGAL_optimisation_precondition(
is_empty() || tco.access_dimension_d_object()( p) == d);
ET sqr_d = sqr_dist( p);
ET h_p_sqr = da_coord(p)[d] * da_coord(p)[d];
return ( ( sqr_d < h_p_sqr * sqr_i_rad_numer) ||
( h_p_sqr * sqr_o_rad_numer < sqr_d)); }
bool is_empty ( ) const { return number_of_points() == 0; }
bool is_degenerate( ) const
{ return ! CGAL_NTS is_positive( sqr_o_rad_numer); }
// modifiers
template < class InputIterator >
void
set( InputIterator first, InputIterator last)
{ if ( points.size() > 0) points.erase( points.begin(), points.end());
std::copy( first, last, std::back_inserter( points));
set_dimension();
CGAL_optimisation_precondition_msg( check_dimension(),
"Not all points have the same dimension.");
compute_min_annulus(); }
void
insert( const Point& p)
{ if ( is_empty()) d = tco.access_dimension_d_object()( p);
CGAL_optimisation_precondition(
tco.access_dimension_d_object()( p) == d);
points.push_back( p);
compute_min_annulus(); }
template < class InputIterator >
void
insert( InputIterator first, InputIterator last)
{ CGAL_optimisation_precondition_code( std::size_t old_n = points.size());
points.insert( points.end(), first, last);
set_dimension();
CGAL_optimisation_precondition_msg( check_dimension( old_n),
"Not all points have the same dimension.");
compute_min_annulus(); }
void
clear( )
{ points.erase( points.begin(), points.end());
compute_min_annulus(); }
// validity check
bool is_valid( bool verbose = false, int level = 0) const;
// traits class access
const Traits& traits( ) const { return tco; }
private:
Traits tco; // traits class object
Access_coordinates_begin_d da_coord; // data accessor
Point_vector points; // input points
int d; // dimension of input points
ET_vector center_coords; // center of small.encl.annulus
ET sqr_i_rad_numer; // squared inner radius of
ET sqr_o_rad_numer; // ---"--- outer ----"----
ET sqr_rad_denom; // smallest enclosing annulus
Solver *solver; // linear programming solver
Index_vector inner_indices;
Index_vector outer_indices;
NT_matrix a_matrix; // matrix `A' of dual LP
NT_vector b_vector; // vector `b' of dual LP
NT_vector c_vector; // vector `c' of dual LP
private:
// squared distance to center * h_p^2 * c_d^2
ET sqr_dist_exact( const Point& p) const
{
ET result(0);
typename Access_coordinates_begin_d::Coordinate_iterator
p_it (da_coord ( p)); // this is p * h_p
ET c_d = center_coords[d];
ET h_p = p_it[d];
for (int i=0; i<d; ++i) {
ET x =
c_d * ET(p_it[i]) - /* this is c_d * p_i * h_p */
h_p * center_coords[i] /* this is h_p * c_i * c_d */ ;
result += x * x;
}
return result;
}
// the function above computes sqr_dist as ||p-c||^2
// (endowed with a factor of c_d^2 * h_p^2)
// but we know that c was computed from (possibly slightly wrong)
// data if NT is inexact; in order to compensate for this, let
// us instead compute sqr_dist as p^Tp - 2c^Tp + c^Tc, where we use
// the (potentially wrong) values of p^Tp and p that went into the
// linear program; this will give us correct containment / on_boundary
// checks also in the inexact-NT case.
ET sqr_dist( const Point& p) const
{
ET result(0), two(2);
NT pTp(0); // computed over input type, possibly slightly wrong
ET cTc(0);
ET two_pTc(0);
typename Access_coordinates_begin_d::Coordinate_iterator
p_it (da_coord ( p)); // this is p * h_p
NT h_p = p_it[d]; // input type!
for (int i=0; i<d; ++i) {
NT p_i (p_it[i]); // input type!
pTp += p_i * p_i; // p_i^2 * h_p^2
cTc += center_coords[i] * center_coords[i]; // c_i^2 * c_d^2
two_pTc +=
// 2 * c_i * c_d * p_i * h_p^2
2 * center_coords[i] * ET(h_p * p_i);
}
ET c_d = center_coords[d];
result =
ET(pTp) * c_d * c_d +
cTc * ET (h_p * h_p) +
- two_pTc * c_d;
return result;
}
// set dimension of input points
void
set_dimension( )
{ d = ( points.size() == 0 ? -1 :
tco.access_dimension_d_object()( points[ 0])); }
// check dimension of input points
bool
check_dimension( std::size_t offset = 0)
{ return ( std::find_if( points.begin()+offset, points.end(),
CGAL::compose1_1( boost::bind2nd(
std::not_equal_to<int>(), d),
tco.access_dimension_d_object()))
== points.end()); }
// compute smallest enclosing annulus
void
compute_min_annulus( )
{
// clear inner and outer support points
inner_indices.erase( inner_indices.begin(), inner_indices.end());
outer_indices.erase( outer_indices.begin(), outer_indices.end());
if ( is_empty()) {
center_coords.resize( 1);
sqr_i_rad_numer = -ET( 1);
sqr_o_rad_numer = -ET( 1);
return;
}
if ( number_of_points() == 1) {
inner_indices.push_back( 0);
outer_indices.push_back( 0);
center_coords.resize( d+1);
std::copy( da_coord( points[ 0]),
da_coord( points[ 0])+d+1,
center_coords.begin());
sqr_i_rad_numer = ET( 0);
sqr_o_rad_numer = ET( 0);
sqr_rad_denom = ET( 1);
return;
}
// set up vector c and solve dual LP
// the ordering of the constraints is as above; the ordering
// of the variables is: z_p_j <-> 2 * j, y_p_j <-> 2 * j + 1
c_vector.resize( 2*points.size());
for ( int j = 0; j < number_of_points(); ++j) {
typename Traits::Access_coordinates_begin_d::Coordinate_iterator
coord_it = da_coord( points[j]);
NT sum = 0;
for ( int i = 0; i < d; ++i) {
sum += NT( coord_it[ i])*NT( coord_it[ i]);
}
c_vector[ 2*j ] = sum;
c_vector[ 2*j+1] = -sum;
}
LP lp (2*static_cast<int>(points.size()), d+2,
A_iterator ( boost::counting_iterator<int>(0),
A_matrix (d, da_coord, points.begin())),
B_iterator ( boost::counting_iterator<int>(0),
B_vector (d)),
R_iterator (CGAL::EQUAL),
c_vector.begin());
Quadratic_program_options options;
options.set_pricing_strategy(pricing_strategy(NT()));
delete solver;
solver = new Solver(lp, options);
CGAL_optimisation_assertion(solver->status() == QP_OPTIMAL);
// compute center and squared radius
ET sqr_sum = 0;
center_coords.resize( ambient_dimension()+1);
for ( int i = 0; i < d; ++i) {
center_coords[ i] = -solver->dual_variable( i);
sqr_sum += center_coords[ i] * center_coords[ i];
}
center_coords[ d] = solver->variables_common_denominator();
sqr_i_rad_numer = sqr_sum
- solver->dual_variable( d )*center_coords[ d];
sqr_o_rad_numer = sqr_sum
- solver->dual_variable( d+1)*center_coords[ d];
sqr_rad_denom = center_coords[ d] * center_coords[ d];
// split up support points
for ( int i = 0; i < solver->number_of_basic_original_variables(); ++i) {
int index = solver->basic_original_variable_indices_begin()[ i];
if ( index % 2 == 0) {
inner_indices.push_back( index/2);
} else {
outer_indices.push_back( index/2);
}
}
}
template < class NT >
Quadratic_program_pricing_strategy pricing_strategy( NT) {
return QP_PARTIAL_FILTERED_DANTZIG;
}
Quadratic_program_pricing_strategy pricing_strategy( ET) {
return QP_PARTIAL_DANTZIG;
}
};
// Function declarations
// =====================
// I/O operators
template < class Traits_ >
std::ostream&
operator << ( std::ostream& os, const Min_annulus_d<Traits_>& min_annulus);
template < class Traits_ >
std::istream&
operator >> ( std::istream& is, Min_annulus_d<Traits_>& min_annulus);
// ============================================================================
// Class implementation
// ====================
// validity check
template < class Traits_ >
bool
Min_annulus_d<Traits_>::
is_valid( bool verbose, int level) const
{
using namespace std;
CGAL::Verbose_ostream verr( verbose);
verr << "CGAL::Min_annulus_d<Traits>::" << endl;
verr << "is_valid( true, " << level << "):" << endl;
verr << " |P| = " << number_of_points()
<< ", |S| = " << number_of_support_points() << endl;
// containment check (a)
// ---------------------
verr << " (a) containment check..." << flush;
Point_iterator point_it = points_begin();
for ( ; point_it != points_end(); ++point_it) {
if ( has_on_unbounded_side( *point_it))
return CGAL::_optimisation_is_valid_fail( verr,
"annulus does not contain all points");
}
verr << "passed." << endl;
// support set check (b)
// ---------------------
verr << " (b) support set check..." << flush;
// all inner support points on inner boundary?
Inner_support_point_iterator i_pt_it = inner_support_points_begin();
for ( ; i_pt_it != inner_support_points_end(); ++i_pt_it) {
ET h_p_sqr = da_coord (*i_pt_it)[d] * da_coord (*i_pt_it)[d];
if ( sqr_dist( *i_pt_it) != h_p_sqr * sqr_i_rad_numer)
return CGAL::_optimisation_is_valid_fail( verr,
"annulus does not have all inner support points on its inner boundary");
}
// all outer support points on outer boundary?
Outer_support_point_iterator o_pt_it = outer_support_points_begin();
for ( ; o_pt_it != outer_support_points_end(); ++o_pt_it) {
ET h_p_sqr = da_coord (*o_pt_it)[d] * da_coord (*o_pt_it)[d];
if ( sqr_dist( *o_pt_it) != h_p_sqr * sqr_o_rad_numer)
return CGAL::_optimisation_is_valid_fail( verr,
"annulus does not have all outer support points on its outer boundary");
}
/*
// center strictly in convex hull of support points?
typename Solver::Basic_variable_numerator_iterator
num_it = solver.basic_variables_numerator_begin();
for ( ; num_it != solver.basic_variables_numerator_end(); ++num_it) {
if ( ! ( CGAL_NTS is_positive( *num_it)
&& *num_it <= solver.variables_common_denominator()))
return CGAL::_optimisation_is_valid_fail( verr,
"center does not lie strictly in convex hull of support points");
}
*/
verr << "passed." << endl;
verr << " object is valid!" << endl;
return( true);
}
// output operator
template < class Traits_ >
std::ostream&
operator << ( std::ostream& os,
const Min_annulus_d<Traits_>& min_annulus)
{
using namespace std;
typedef typename Min_annulus_d<Traits_>::Point Point;
typedef ostream_iterator<Point> Os_it;
typedef typename Traits_::ET ET;
typedef ostream_iterator<ET> Et_it;
switch ( CGAL::get_mode( os)) {
case CGAL::IO::PRETTY:
os << "CGAL::Min_annulus_d( |P| = "
<< min_annulus.number_of_points() << ", |S| = "
<< min_annulus.number_of_inner_support_points() << '+'
<< min_annulus.number_of_outer_support_points() << endl;
os << " P = {" << endl;
os << " ";
copy( min_annulus.points_begin(), min_annulus.points_end(),
Os_it( os, ",\n "));
os << "}" << endl;
os << " S_i = {" << endl;
os << " ";
copy( min_annulus.inner_support_points_begin(),
min_annulus.inner_support_points_end(),
Os_it( os, ",\n "));
os << "}" << endl;
os << " S_o = {" << endl;
os << " ";
copy( min_annulus.outer_support_points_begin(),
min_annulus.outer_support_points_end(),
Os_it( os, ",\n "));
os << "}" << endl;
os << " center = ( ";
copy( min_annulus.center_coordinates_begin(),
min_annulus.center_coordinates_end(),
Et_it( os, " "));
os << ")" << endl;
os << " squared inner radius = "
<< min_annulus.squared_inner_radius_numerator() << " / "
<< min_annulus.squared_radii_denominator() << endl;
os << " squared outer radius = "
<< min_annulus.squared_outer_radius_numerator() << " / "
<< min_annulus.squared_radii_denominator() << endl;
break;
case CGAL::IO::ASCII:
copy( min_annulus.points_begin(), min_annulus.points_end(),
Os_it( os, "\n"));
break;
case CGAL::IO::BINARY:
copy( min_annulus.points_begin(), min_annulus.points_end(),
Os_it( os));
break;
default:
CGAL_optimisation_assertion_msg( false,
"CGAL::get_mode( os) invalid!");
break; }
return( os);
}
// input operator
template < class Traits_ >
std::istream&
operator >> ( std::istream& is, CGAL::Min_annulus_d<Traits_>& min_annulus)
{
using namespace std;
switch ( CGAL::get_mode( is)) {
case CGAL::IO::PRETTY:
cerr << endl;
cerr << "Stream must be in ascii or binary mode" << endl;
break;
case CGAL::IO::ASCII:
case CGAL::IO::BINARY:
typedef typename CGAL::Min_annulus_d<Traits_>::Point Point;
typedef istream_iterator<Point> Is_it;
min_annulus.set( Is_it( is), Is_it());
break;
default:
CGAL_optimisation_assertion_msg( false, "CGAL::IO::mode invalid!");
break; }
return( is);
}
} //namespace CGAL
#ifdef _MSC_VER
# pragma warning(pop)
#endif
#endif // CGAL_MIN_ANNULUS_D_H
// ===== EOF ==================================================================