1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
|
#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<3> >;
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 and weights from a small molecule
// ----------------------------------------------------------------------------
Vector_of_points points;
points.emplace_back(Bare_point(1, -1, -1), 4.);
points.emplace_back(Bare_point(-1, 1, -1), 4.);
points.emplace_back(Bare_point(-1, -1, 1), 4.);
points.emplace_back(Bare_point(1, 1, 1), 4.);
points.emplace_back(Bare_point(2, 2, 2), 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;
}
|
