cgal/Principal_component_analysis/test/Principal_component_analysis/fitting.C

104 lines
2.6 KiB
C

// test for the linear_least_square_fitting() functions.
#include <vector>
#include <cassert>
#include <stdlib.h>
#include <CGAL/Cartesian.h>
#include <CGAL/copy_n.h>
#include <CGAL/linear_least_squares_fitting_2.h>
#include <CGAL/linear_least_squares_fitting_3.h>
#include <CGAL/point_generators_2.h>
// types
typedef CGAL::Cartesian<double> Kernel;
typedef Kernel::FT FT;
typedef Kernel::Line_2 Line_2;
typedef Kernel::Point_2 Point_2;
typedef Kernel::Triangle_2 Triangle_2;
typedef Kernel::Vector_2 Vector_2;
typedef Kernel::Line_3 Line_3;
typedef Kernel::Point_3 Point_3;
typedef Kernel::Triangle_3 Triangle_3;
// case with only one point in container
// the fitting line must be horizontal by default
void test_2D()
{
std::vector<Point_2> points;
points.push_back(Point_2(0.0,0.0));
// fit a line
// call all versions of the function
std::cout << "fit 2D line...";
Kernel k;
Line_2 line;
Point_2 centroid;
FT quality;
quality = linear_least_squares_fitting_2(points.begin(),points.end(),line);
quality = linear_least_squares_fitting_2(points.begin(),points.end(),line,centroid);
quality = linear_least_squares_fitting_2(points.begin(),points.end(),line,centroid,k);
std::cout << "done (quality: " << quality << ")" << std::endl;
if(!line.is_horizontal())
{
std::cout << "failure" << std::endl;
exit(1); // failure
}
}
// case with a point set on a horizontal segment
// the fitting line must be horizontal
void test_2D_point_set(const unsigned int nb_points)
{
// create points on a horizontal segment
Point_2 p(0.0,0.5);
Point_2 q(1.0,0.5);
std::cout << "generate " << nb_points <<
" 2D points on a horizontal line...";
std::list<Point_2> points;
points_on_segment_2(p,q,100,std::back_inserter(points));
std::cout << "done " << std::endl;
// fit a line
std::cout << "fit 2D line...";
Line_2 line;
Point_2 centroid;
// call all versions of the function
FT quality;
Kernel k;
quality = linear_least_squares_fitting_2(points.begin(),points.end(),line);
quality = linear_least_squares_fitting_2(points.begin(),points.end(),line,centroid);
quality = linear_least_squares_fitting_2(points.begin(),points.end(),line,centroid,k);
std::cout << "done (quality: " << quality << ")" << std::endl;
if(!line.is_horizontal())
{
std::cout << "failure" << std::endl;
exit(1); // failure
}
}
int main()
{
std::cout << "Test linear_least_squares_fitting" << std::endl;
// 2D
test_2D();
test_2D_point_set(100);
// 3D
// test_3D();
// test_3D_point_set(100);
// test_3D_triangle_set(100);
return 0; // success
}