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sparse_rips_distance_matrix_persistence.cpp
/* 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): Marc Glisse, Clément Maria
*
* Modification(s):
* VR - March 2019: Use distance matrix constructor for Sparse rips
*
* Copyright (C) 2018 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/>.
*/
#include <gudhi/Sparse_rips_complex.h>
#include <gudhi/Simplex_tree.h>
#include <gudhi/Persistent_cohomology.h>
#include <gudhi/reader_utils.h>
#include <boost/program_options.hpp>
#include <string>
#include <vector>
// Types definition
using Simplex_tree = Gudhi::Simplex_tree<Gudhi::Simplex_tree_options_fast_persistence>;
using Filtration_value = Simplex_tree::Filtration_value;
using Sparse_rips = Gudhi::rips_complex::Sparse_rips_complex<Filtration_value>;
using Field_Zp = Gudhi::persistent_cohomology::Field_Zp;
using Persistent_cohomology = Gudhi::persistent_cohomology::Persistent_cohomology<Simplex_tree, Field_Zp>;
using Distance_matrix = std::vector<std::vector<Filtration_value>>;
void program_options(int argc, char* argv[], std::string& csv_matrix_file, std::string& filediag, double& epsilon,
int& dim_max, int& p, Filtration_value& min_persistence);
int main(int argc, char* argv[]) {
std::string csv_matrix_file;
std::string filediag;
double epsilon;
int dim_max;
int p;
Filtration_value min_persistence;
program_options(argc, argv, csv_matrix_file, filediag, epsilon, dim_max, p, min_persistence);
Distance_matrix distances = Gudhi::read_lower_triangular_matrix_from_csv_file<Filtration_value>(csv_matrix_file);
Sparse_rips sparse_rips(distances, epsilon);
// Construct the Rips complex in a Simplex Tree
Simplex_tree simplex_tree;
sparse_rips.create_complex(simplex_tree, dim_max);
std::cout << "The complex contains " << simplex_tree.num_simplices() << " simplices \n";
std::cout << " and has dimension " << simplex_tree.dimension() << " \n";
// Sort the simplices in the order of the filtration
simplex_tree.initialize_filtration();
// Compute the persistence diagram of the complex
Persistent_cohomology pcoh(simplex_tree);
// initializes the coefficient field for homology
pcoh.init_coefficients(p);
pcoh.compute_persistent_cohomology(min_persistence);
// Output the diagram in filediag
if (filediag.empty()) {
pcoh.output_diagram();
} else {
std::ofstream out(filediag);
pcoh.output_diagram(out);
out.close();
}
return 0;
}
void program_options(int argc, char* argv[], std::string& csv_matrix_file, std::string& filediag, double& epsilon,
int& dim_max, int& p, Filtration_value& min_persistence) {
namespace po = boost::program_options;
po::options_description hidden("Hidden options");
hidden.add_options()(
"input-file", po::value<std::string>(&csv_matrix_file),
"Name of file containing a distance matrix. Can be square or lower triangular matrix. Separator is ';'.");
po::options_description visible("Allowed options", 100);
visible.add_options()("help,h", "produce help message")(
"output-file,o", po::value<std::string>(&filediag)->default_value(std::string()),
"Name of file in which the persistence diagram is written. Default print in std::cout")(
"approximation,e", po::value<double>(&epsilon)->default_value(.5),
"Epsilon, where the sparse Rips complex is a (1+epsilon)-approximation of the Rips complex.")(
"cpx-dimension,d", po::value<int>(&dim_max)->default_value(1),
"Maximal dimension of the Rips complex we want to compute.")(
"field-charac,p", po::value<int>(&p)->default_value(11),
"Characteristic p of the coefficient field Z/pZ for computing homology.")(
"min-persistence,m", po::value<Filtration_value>(&min_persistence),
"Minimal lifetime of homology feature to be recorded. Default is 0. Enter a negative value to see zero length "
"intervals");
po::positional_options_description pos;
pos.add("input-file", 1);
po::options_description all;
all.add(visible).add(hidden);
po::variables_map vm;
po::store(po::command_line_parser(argc, argv).options(all).positional(pos).run(), vm);
po::notify(vm);
if (vm.count("help") || !vm.count("input-file")) {
std::cout << std::endl;
std::cout << "Compute the persistent homology with coefficient field Z/pZ \n";
std::cout << "of a sparse (1+epsilon)-approximation of the Rips complex \n";
std::cout << "defined on a set of distance matrix.\n \n";
std::cout << "The output diagram contains one bar per line, written with the convention: \n";
std::cout << " p dim b d \n";
std::cout << "where dim is the dimension of the homological feature,\n";
std::cout << "b and d are respectively the birth and death of the feature and \n";
std::cout << "p is the characteristic of the field Z/pZ used for homology coefficients." << std::endl << std::endl;
std::cout << "Usage: " << argv[0] << " [options] input-file" << std::endl << std::endl;
std::cout << visible << std::endl;
exit(-1);
}
}
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