diff options
Diffstat (limited to 'src/Alpha_complex/example/Alpha_complex_3d_from_points.cpp')
-rw-r--r-- | src/Alpha_complex/example/Alpha_complex_3d_from_points.cpp | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/src/Alpha_complex/example/Alpha_complex_3d_from_points.cpp b/src/Alpha_complex/example/Alpha_complex_3d_from_points.cpp new file mode 100644 index 00000000..0e359a27 --- /dev/null +++ b/src/Alpha_complex/example/Alpha_complex_3d_from_points.cpp @@ -0,0 +1,56 @@ +#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 Alpha_complex_3d = Gudhi::alpha_complex::Alpha_complex_3d<Gudhi::alpha_complex::complexity::SAFE, false, false>; +using Point = Alpha_complex_3d::Point_3; +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); + + Gudhi::Simplex_tree<> simplex; + if (alpha_complex_from_points.create_complex(simplex)) { + // ---------------------------------------------------------------------------- + // Display information about the alpha complex + // ---------------------------------------------------------------------------- + std::cout << "Alpha complex is of dimension " << simplex.dimension() << " - " << simplex.num_simplices() + << " simplices - " << simplex.num_vertices() << " vertices." << std::endl; + + std::cout << "Iterator on alpha complex simplices in the filtration order, with [filtration value]:" << std::endl; + for (auto f_simplex : simplex.filtration_simplex_range()) { + std::cout << " ( "; + for (auto vertex : simplex.simplex_vertex_range(f_simplex)) { + std::cout << vertex << " "; + } + std::cout << ") -> " + << "[" << simplex.filtration(f_simplex) << "] "; + std::cout << std::endl; + } + } + return 0; +} |