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#include <gudhi/Alpha_complex.h>
// to construct a simplex_tree from alpha complex
#include <gudhi/Simplex_tree.h>
#include <CGAL/Epeck_d.h>
#include <iostream>
#include <vector>
// Explicit dimension 2 Epeck_d kernel
using Kernel = CGAL::Epeck_d< CGAL::Dimension_tag<2> >;
using Bare_point = Kernel::Point_d;
using Weighted_point = Kernel::Weighted_point_d;
using Vector_of_points = std::vector<Weighted_point>;
int main() {
// ----------------------------------------------------------------------------
// Init of a list of points
// ----------------------------------------------------------------------------
Vector_of_points points;
points.push_back(Weighted_point(Bare_point(1.0, 1.0) , 1.));
points.push_back(Weighted_point(Bare_point(7.0, 0.0) , 1.));
points.push_back(Weighted_point(Bare_point(4.0, 6.0) , 1.));
points.push_back(Weighted_point(Bare_point(9.0, 6.0) , 1.));
points.push_back(Weighted_point(Bare_point(0.0, 14.0), 1.));
points.push_back(Weighted_point(Bare_point(2.0, 19.0), 1.));
points.push_back(Weighted_point(Bare_point(9.0, 17.0), 1.));
// ----------------------------------------------------------------------------
// Init of an alpha complex from the list of points
// ----------------------------------------------------------------------------
Gudhi::alpha_complex::Alpha_complex<Kernel, true> alpha_complex_from_weighted_points(points);
Gudhi::Simplex_tree<> simplex;
if (alpha_complex_from_weighted_points.create_complex(simplex)) {
// ----------------------------------------------------------------------------
// Display information about the alpha complex
// ----------------------------------------------------------------------------
std::clog << "Weighted alpha complex is of dimension " << simplex.dimension() <<
" - " << simplex.num_simplices() << " simplices - " <<
simplex.num_vertices() << " vertices." << std::endl;
std::clog << "Iterator on weighted alpha complex simplices in the filtration order, with [filtration value]:" << std::endl;
for (auto f_simplex : simplex.filtration_simplex_range()) {
std::clog << " ( ";
for (auto vertex : simplex.simplex_vertex_range(f_simplex)) {
std::clog << vertex << " ";
}
std::clog << ") -> " << "[" << simplex.filtration(f_simplex) << "] ";
std::clog << std::endl;
}
}
return 0;
}
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