diff options
| -rw-r--r-- | src/Rips_complex/include/gudhi/Sparse_rips_complex.h | 169 | ||||
| -rw-r--r-- | src/Rips_complex/utilities/sparse_rips_persistence.cpp | 145 |
2 files changed, 314 insertions, 0 deletions
diff --git a/src/Rips_complex/include/gudhi/Sparse_rips_complex.h b/src/Rips_complex/include/gudhi/Sparse_rips_complex.h new file mode 100644 index 00000000..c5378b6e --- /dev/null +++ b/src/Rips_complex/include/gudhi/Sparse_rips_complex.h @@ -0,0 +1,169 @@ +/* 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 + * + * 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/>. + */ + +#ifndef SPARSE_RIPS_COMPLEX_H_ +#define SPARSE_RIPS_COMPLEX_H_ + +#include <gudhi/Debug_utils.h> +#include <gudhi/graph_simplicial_complex.h> +#include <gudhi/choose_n_farthest_points.h> + +#include <boost/graph/adjacency_list.hpp> +#include <boost/range/metafunctions.hpp> + +#include <vector> + + +namespace Gudhi { + +namespace rips_complex { + +// The whole interface is copied on Rips_complex. A redesign should be discussed with all complex creation classes in mind. + +/** + * \class Sparse_rips_complex + * \brief Sparse Rips complex data structure. + * + * \ingroup rips_complex + * + * \details + * This class is used to construct a sparse \f$(1+\epsilon)\f$-approximation of `Rips_complex`. + * + * \tparam Filtration_value is the type used to store the filtration values of the simplicial complex. + */ +template<typename Filtration_value> +class Sparse_rips_complex { + private: + // TODO: use a different graph where we know we can safely insert in parallel. + typedef typename boost::adjacency_list<boost::vecS, boost::vecS, boost::undirectedS + , boost::property<vertex_filtration_t, Filtration_value> + , boost::property<edge_filtration_t, Filtration_value>> Graph; + + typedef int Vertex_handle; + + public: + /** \brief Sparse_rips_complex constructor from a list of points. + * + * @param[in] points Range of points. + * @param[in] distance distance function that returns a `Filtration_value` from 2 given points. + * + */ + template<typename RandomAccessPointRange, typename Distance > + Sparse_rips_complex(const RandomAccessPointRange& points, Distance distance, double epsilon) { + std::vector<Vertex_handle> sorted_points; + std::vector<Filtration_value> params; + auto dist_fun = [&](Vertex_handle i, Vertex_handle j){return distance(points[i], points[j]);}; + Ker<decltype(dist_fun)> kernel(dist_fun); + subsampling::choose_n_farthest_points(kernel, boost::irange<Vertex_handle>(0, boost::size(points)), -1, -1, std::back_inserter(sorted_points), std::back_inserter(params)); + compute_sparse_graph(sorted_points, params, dist_fun, epsilon); + } + + /** \brief Rips_complex constructor from a distance matrix. + * + * @param[in] distance_matrix Range of range of distances. + * `distance_matrix[i][j]` returns the distance between points \f$i\f$ and + * \f$j\f$ as long as \f$ 0 \leqslant i < j \leqslant + * distance\_matrix.size().\f$ + */ + template<typename DistanceMatrix> + Sparse_rips_complex(const DistanceMatrix& distance_matrix, double epsilon) + : Sparse_rips_complex( + boost::irange<Vertex_handle>(0, boost::size(distance_matrix)), + [&](Vertex_handle i, Vertex_handle j){return distance_matrix[j][i];}, + epsilon) {} + + /** \brief Fills the simplicial complex with the sparse Rips graph and + * expands it with all the cliques, stopping at a given maximal dimension. + * + * \tparam SimplicialComplexForRips must meet `SimplicialComplexForRips` concept. + * + * @param[in] complex the complex to fill + * @param[in] dim_max maximal dimension of the simplicial complex. + * @exception std::invalid_argument In debug mode, if `complex.num_vertices()` does not return 0. + * + */ + template <typename SimplicialComplexForRips> + void create_complex(SimplicialComplexForRips& complex, int dim_max) { + GUDHI_CHECK(complex.num_vertices() == 0, + std::invalid_argument("Sparse_rips_complex::create_complex - simplicial complex is not empty")); + + complex.insert_graph(graph_); + complex.expansion(dim_max); + } + + private: + // choose_n_farthest_points wants the distance function in this form... + template <class Distance> + struct Ker { + typedef std::size_t Point_d; // index into point range + Ker(Distance& d) : dist (d) {} + // Despite the name, this is not squared... + typedef Distance Squared_distance_d; + Squared_distance_d& squared_distance_d_object() const { return dist; } + Distance& dist; + }; + + // PointRange must be random access. + template<typename PointRange, typename ParamRange, typename Distance> + void compute_sparse_graph(const PointRange& points, const ParamRange& params, Distance& dist, double epsilon) { + const int n = boost::size(points); + graph_.~Graph(); + new(&graph_) Graph(n); + //for(auto v : vertices(g)) // doesn't work :-( + typename boost::graph_traits<Graph>::vertex_iterator v_i, v_e; + for(std::tie(v_i, v_e) = vertices(graph_); v_i != v_e; ++v_i) { + auto v = *v_i; + // This whole loop might not be necessary, leave it until someone investigates if it is safe to remove. + put(vertex_filtration_t(), graph_, v, 0); + } + + // TODO: + // - make it parallel + // - only test near-enough neighbors + for(int i = 0; i < n; ++i) + for(int j = i + 1; j < n; ++j){ + auto&& pi = points[i]; + auto&& pj = points[j]; + auto d = dist(pi, pj); + auto li = params[i]; + auto lj = params[j]; + GUDHI_CHECK(lj <= li, "Bad furthest point sorting"); + Filtration_value alpha; + + if(d * epsilon <= 2 * lj) + alpha = d / 2; + else if(d * epsilon <= li + lj && (epsilon >= 1 || d * epsilon <= lj * (1 + 1 / (1 - epsilon)))) + alpha = d - lj / epsilon; + else continue; + + add_edge(pi, pj, alpha, graph_); + } + } + + Graph graph_; +}; + +} // namespace rips_complex + +} // namespace Gudhi + +#endif // SPARSE_RIPS_COMPLEX_H_ diff --git a/src/Rips_complex/utilities/sparse_rips_persistence.cpp b/src/Rips_complex/utilities/sparse_rips_persistence.cpp new file mode 100644 index 00000000..12b3b099 --- /dev/null +++ b/src/Rips_complex/utilities/sparse_rips_persistence.cpp @@ -0,0 +1,145 @@ +/* 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 + * + * Copyright (C) 2014 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/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 + , 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; + double epsilon; + int dim_max; + int p; + Filtration_value min_persistence; + + program_options(argc, argv, off_file_points, filediag, 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); + + // 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 & off_file_points + , 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>(&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 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 \ndefined on a set of input points.\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; + std::abort(); + } +} |