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sparse_rips_persistence.cpp
/* This file is part of the Gudhi Library - https://gudhi.inria.fr/ - which is released under MIT.
* See file LICENSE or go to https://gudhi.inria.fr/licensing/ for full license details.
* Author(s): Marc Glisse, Clément Maria
*
* Copyright (C) 2018 Inria
*
* Modification(s):
* - YYYY/MM Author: Description of the modification
*/
#include <gudhi/Sparse_rips_complex.h>
#include <gudhi/distance_functions.h>
#include <gudhi/Simplex_tree.h>
#include <gudhi/Persistent_cohomology.h>
#include <gudhi/Points_off_io.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 Point = std::vector<double>;
using Points_off_reader = Gudhi::Points_off_reader<Point>;
void program_options(int argc, char* argv[], std::string& off_file_points, std::string& filediag,
Filtration_value& threshold, double& epsilon,
int& dim_max, int& p, Filtration_value& min_persistence);
int main(int argc, char* argv[]) {
std::string off_file_points;
std::string filediag;
Filtration_value threshold;
double epsilon;
int dim_max;
int p;
Filtration_value min_persistence;
program_options(argc, argv, off_file_points, filediag, threshold, epsilon, dim_max, p, min_persistence);
Points_off_reader off_reader(off_file_points);
Sparse_rips sparse_rips(off_reader.get_point_cloud(), Gudhi::Euclidean_distance(), epsilon,
-std::numeric_limits<Filtration_value>::infinity(), threshold);
// Construct the Rips complex in a Simplex Tree
Simplex_tree simplex_tree;
sparse_rips.create_complex(simplex_tree, dim_max);
std::clog << "The complex contains " << simplex_tree.num_simplices() << " simplices \n";
std::clog << " and has dimension " << simplex_tree.dimension() << " \n";
// 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& off_file_points, std::string& filediag,
Filtration_value& threshold, 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>(&off_file_points),
"Name of an OFF file containing a point set.\n");
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 standard output")(
"max-edge-length,r",
po::value<Filtration_value>(&threshold)->default_value(std::numeric_limits<Filtration_value>::infinity()),
"Maximal length of an edge for the Rips complex construction.")(
"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(std::numeric_limits<int>::max()),
"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::clog << std::endl;
std::clog << "Compute the persistent homology with coefficient field Z/pZ \n";
std::clog << "of a sparse 1/(1-epsilon)-approximation of the Rips complex \ndefined on a set of input points.\n \n";
std::clog << "The output diagram contains one bar per line, written with the convention: \n";
std::clog << " p dim b d \n";
std::clog << "where dim is the dimension of the homological feature,\n";
std::clog << "b and d are respectively the birth and death of the feature and \n";
std::clog << "p is the characteristic of the field Z/pZ used for homology coefficients." << std::endl << std::endl;
std::clog << "Usage: " << argv[0] << " [options] input-file" << std::endl << std::endl;
std::clog << visible << std::endl;
exit(-1);
}
}
Gudhi::Euclidean_distance
Compute the Euclidean distance between two Points given by a range of coordinates....
Definition distance_functions.h:32
Gudhi::Points_off_reader
OFF file reader implementation in order to read points from an OFF file.
Definition Points_off_io.h:122
Gudhi::Simplex_tree
Simplex Tree data structure for representing simplicial complexes.
Definition Simplex_tree.h:98
Gudhi::Simplex_tree< Gudhi::Simplex_tree_options_fast_persistence >::Filtration_value
Options::Filtration_value Filtration_value
Definition Simplex_tree.h:105
Gudhi::Simplex_tree::num_simplices
size_t num_simplices() const
Returns the number of simplices in the simplex_tree.
Definition Simplex_tree.h:791
Gudhi::persistent_cohomology::Field_Zp
Structure representing the coefficient field .
Definition Field_Zp.h:27
Gudhi::persistent_cohomology::Persistent_cohomology
Computes the persistent cohomology of a filtered complex.
Definition Persistent_cohomology.h:54
Gudhi::rips_complex::Sparse_rips_complex
Sparse Rips complex data structure.
Definition Sparse_rips_complex.h:104
distance_functions.h
Global distance functions.