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/* This file is part of the Gudhi Library. The Gudhi library
* (Geometric Understanding in Higher Dimensions) is a generic C++
* library for computational topology.
*
* Author(s): Vincent Rouvreau
*
* Copyright (C) 2016 INRIA
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
#ifndef WITNESS_COMPLEX_INTERFACE_H
#define WITNESS_COMPLEX_INTERFACE_H
#include <gudhi/Simplex_tree.h>
#include <gudhi/Witness_complex.h>
#include <gudhi/Construct_closest_landmark_table.h>
#include <gudhi/pick_n_random_points.h>
#include "Persistent_cohomology_interface.h"
#include <vector>
#include <utility> // std::pair
#include <iostream>
namespace Gudhi {
namespace witness_complex {
class Witness_complex_interface {
typedef typename Simplex_tree<>::Simplex_handle Simplex_handle;
typedef typename Simplex_tree<>::Filtration_value Filtration_value;
typedef typename Simplex_tree<>::Vertex_handle Vertex_handle;
typedef typename std::pair<Simplex_handle, bool> Insertion_result;
using Simplex = std::vector<Vertex_handle>;
using Filtered_complex = std::pair<Simplex, Filtration_value>;
using Complex_tree = std::vector<Filtered_complex>;
public:
Witness_complex_interface(std::vector<std::vector<double>>&points, int number_of_landmarks)
: pcoh_(nullptr) {
std::vector<std::vector< int > > knn;
std::vector<std::vector<double>> landmarks;
Gudhi::subsampling::pick_n_random_points(points, number_of_landmarks, std::back_inserter(landmarks));
Gudhi::witness_complex::construct_closest_landmark_table<Filtration_value>(points, landmarks, knn);
Gudhi::witness_complex::witness_complex(knn, number_of_landmarks, points[0].size(), simplex_tree_);
}
bool find_simplex(const Simplex& vh) {
return (simplex_tree_.find(vh) != simplex_tree_.null_simplex());
}
bool insert_simplex_and_subfaces(const Simplex& complex, Filtration_value filtration = 0) {
Insertion_result result = simplex_tree_.insert_simplex_and_subfaces(complex, filtration);
return (result.second);
}
Filtration_value simplex_filtration(const Simplex& complex) {
return simplex_tree_.filtration(simplex_tree_.find(complex));
}
void remove_maximal_simplex(const Simplex& complex) {
return simplex_tree_.remove_maximal_simplex(simplex_tree_.find(complex));
}
Complex_tree get_filtered_tree() {
Complex_tree filtered_tree;
for (auto f_simplex : simplex_tree_.filtration_simplex_range()) {
Simplex simplex;
for (auto vertex : simplex_tree_.simplex_vertex_range(f_simplex)) {
simplex.insert(simplex.begin(), vertex);
}
filtered_tree.push_back(std::make_pair(simplex, simplex_tree_.filtration(f_simplex)));
}
return filtered_tree;
}
Complex_tree get_skeleton_tree(int dimension) {
Complex_tree skeleton_tree;
for (auto f_simplex : simplex_tree_.skeleton_simplex_range(dimension)) {
Simplex simplex;
for (auto vertex : simplex_tree_.simplex_vertex_range(f_simplex)) {
simplex.insert(simplex.begin(), vertex);
}
skeleton_tree.push_back(std::make_pair(simplex, simplex_tree_.filtration(f_simplex)));
}
return skeleton_tree;
}
Complex_tree get_star_tree(const Simplex& complex) {
Complex_tree star_tree;
for (auto f_simplex : simplex_tree_.star_simplex_range(simplex_tree_.find(complex))) {
Simplex simplex;
for (auto vertex : simplex_tree_.simplex_vertex_range(f_simplex)) {
simplex.insert(simplex.begin(), vertex);
}
star_tree.push_back(std::make_pair(simplex, simplex_tree_.filtration(f_simplex)));
}
return star_tree;
}
Complex_tree get_coface_tree(const Simplex& complex, int dimension) {
Complex_tree coface_tree;
for (auto f_simplex : simplex_tree_.cofaces_simplex_range(simplex_tree_.find(complex), dimension)) {
Simplex simplex;
for (auto vertex : simplex_tree_.simplex_vertex_range(f_simplex)) {
simplex.insert(simplex.begin(), vertex);
}
coface_tree.push_back(std::make_pair(simplex, simplex_tree_.filtration(f_simplex)));
}
return coface_tree;
}
// Specific to Witness complex because no inheritance
Filtration_value filtration() const {
return simplex_tree_.filtration();
}
void set_filtration(Filtration_value fil) {
simplex_tree_.set_filtration(fil);
}
void initialize_filtration() {
simplex_tree_.initialize_filtration();
}
size_t num_vertices() const {
return simplex_tree_.num_vertices();
}
size_t num_simplices() {
return simplex_tree_.num_simplices();
}
int dimension() const {
return simplex_tree_.dimension();
}
void set_dimension(int dimension) {
simplex_tree_.set_dimension(dimension);
}
std::vector<std::pair<int, std::pair<double, double>>> get_persistence(int homology_coeff_field, double min_persistence) {
if (pcoh_ != nullptr) {
delete pcoh_;
}
pcoh_ = new Persistent_cohomology_interface<Simplex_tree<>>(&simplex_tree_);
return pcoh_->get_persistence(homology_coeff_field, min_persistence);
}
std::vector<int> get_betti_numbers() const {
if (pcoh_ != nullptr) {
return pcoh_->betti_numbers();
}
std::vector<int> betti_numbers;
return betti_numbers;
}
std::vector<int> get_persistent_betti_numbers(Filtration_value from, Filtration_value to) const {
if (pcoh_ != nullptr) {
return pcoh_->persistent_betti_numbers(from, to);
}
std::vector<int> persistent_betti_numbers;
return persistent_betti_numbers;
}
private:
Simplex_tree<> simplex_tree_;
Persistent_cohomology_interface<Simplex_tree<>>* pcoh_;
};
} // namespace witness_complex
} // namespace Gudhi
#endif // WITNESS_COMPLEX_INTERFACE_H
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