Alpha_complex_3d_from_points.cpp
#include <gudhi/Alpha_complex_3d.h>
// to construct a simplex_tree from alpha complex
#include <gudhi/Simplex_tree.h>
#include <iostream>
#include <string>
#include <vector>
#include <limits> // for numeric limits
using Vector_of_points = std::vector<Point>;
int main(int argc, char **argv) {
if (argc != 1) {
std::cerr << "Error: Number of arguments (" << argc << ") is not correct\n";
std::cerr << "Usage: " << (argv[0] - 1) << " \n";
exit(-1); // ----- >>
}
// ----------------------------------------------------------------------------
// Init of a list of points from a small molecule
// ----------------------------------------------------------------------------
Vector_of_points points;
points.push_back(Point(1, -1, -1));
points.push_back(Point(-1, 1, -1));
points.push_back(Point(-1, -1, 1));
points.push_back(Point(1, 1, 1));
points.push_back(Point(2, 2, 2));
// ----------------------------------------------------------------------------
// Init of an alpha complex from the list of points
// ----------------------------------------------------------------------------
Alpha_complex_3d alpha_complex_from_points(points);
if (alpha_complex_from_points.create_complex(simplex)) {
// ----------------------------------------------------------------------------
// Display information about the alpha complex
// ----------------------------------------------------------------------------
std::clog << "Alpha complex is of dimension " << simplex.dimension() << " - " << simplex.num_simplices()
<< " simplices - " << simplex.num_vertices() << " vertices." << std::endl;
std::clog << "Iterator on 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;
}
Simplex Tree data structure for representing simplicial complexes.
Definition: Simplex_tree.h:95
Filtration_simplex_range const & filtration_simplex_range(Indexing_tag=Indexing_tag())
Returns a range over the simplices of the simplicial complex, in the order of the filtration.
Definition: Simplex_tree.h:338
Simplex_vertex_range simplex_vertex_range(Simplex_handle sh) const
Returns a range over the vertices of a simplex.
Definition: Simplex_tree.h:349
static Filtration_value filtration(Simplex_handle sh)
Returns the filtration value of a simplex.
Definition: Simplex_tree.h:614
size_t num_vertices() const
Returns the number of vertices in the complex.
Definition: Simplex_tree.h:651
size_t num_simplices()
Returns the number of simplices in the simplex_tree.
Definition: Simplex_tree.h:664
Alpha complex data structure for 3d specific case.
Definition: Alpha_complex_3d.h:118
bool create_complex(SimplicialComplexForAlpha3d &complex, Filtration_value max_alpha_square=std::numeric_limits< Filtration_value >::infinity())
Inserts all Delaunay triangulation into the simplicial complex. It also computes the filtration value...
Definition: Alpha_complex_3d.h:435
typename Alpha_shape_3::Point Point_3
Alpha_complex_3d::Point_3 type is either a Alpha_complex_3d::Bare_point_3 (Weighted = false) or a Alp...
Definition: Alpha_complex_3d.h:248