From ab6c280bd1de67a533d5ed357c39d798c1cf30c3 Mon Sep 17 00:00:00 2001 From: skachano Date: Sat, 21 Jan 2017 11:02:41 +0000 Subject: Added the Euclidean files -_- git-svn-id: svn+ssh://scm.gforge.inria.fr/svnroot/gudhi/branches/relaxed-witness@1981 636b058d-ea47-450e-bf9e-a15bfbe3eedb Former-commit-id: e7b06da298f5cf07658dc20302eb1da9a08b424c --- .../gudhi/Euclidean_strong_witness_complex.h | 208 +++++++++++++++++++++ 1 file changed, 208 insertions(+) create mode 100644 src/Witness_complex/include/gudhi/Euclidean_strong_witness_complex.h (limited to 'src/Witness_complex/include/gudhi/Euclidean_strong_witness_complex.h') diff --git a/src/Witness_complex/include/gudhi/Euclidean_strong_witness_complex.h b/src/Witness_complex/include/gudhi/Euclidean_strong_witness_complex.h new file mode 100644 index 00000000..38fa5c22 --- /dev/null +++ b/src/Witness_complex/include/gudhi/Euclidean_strong_witness_complex.h @@ -0,0 +1,208 @@ +/* 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): Siargey Kachanovich + * + * Copyright (C) 2015 INRIA (France) + * + * 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 . + */ + +#ifndef EUCLIDEAN_STRONG_WITNESS_COMPLEX_H_ +#define EUCLIDEAN_STRONG_WITNESS_COMPLEX_H_ + +#include +#include +#include +#include + +#include +#include + +namespace Gudhi { + +namespace witness_complex { + +/** + * \private + * \class Euclidean_strong_witness_complex + * \brief Constructs strong witness complex for given sets of witnesses and landmarks in Euclidean space. + * \ingroup witness_complex + * + * \tparam Kernel_ requires a CGAL::Epick_d class. + */ +template< class Kernel_ > +class Euclidean_strong_witness_complex { +private: + typedef Kernel_ K; + typedef typename K::Point_d Point_d; + typedef typename K::FT FT; + typedef std::vector Point_range; + typedef Gudhi::spatial_searching::Kd_tree_search Kd_tree; + typedef typename Kd_tree::INS_range Nearest_landmark_range; + typedef typename std::vector Nearest_landmark_table; + typedef typename Nearest_landmark_range::iterator Nearest_landmark_row_iterator; + + typedef FT Filtration_value; + + + typedef std::size_t Witness_id; + typedef typename Nearest_landmark_range::Point_with_transformed_distance Id_distance_pair; + typedef typename Id_distance_pair::first_type Landmark_id; + typedef Active_witness ActiveWitness; + typedef std::list< ActiveWitness > ActiveWitnessList; + typedef std::vector< Landmark_id > typeVectorVertex; + typedef std::pair< typeVectorVertex, Filtration_value> typeSimplex; + + typedef Landmark_id Vertex_handle; + + private: + Point_range witnesses_, landmarks_; + Kd_tree landmark_tree_; + + public: + ///////////////////////////////////////////////////////////////////////////////////////////////////////////////////// + /* @name Constructor + */ + + //@{ + + /** + * \brief Initializes member variables before constructing simplicial complex. + * \details Records landmarks from the range 'landmarks' into a + * table internally, as well as witnesses from the range 'witnesses'. + * Both ranges should have value_type Kernel_::Point_d. + */ + template< typename LandmarkRange, + typename WitnessRange > + Euclidean_strong_witness_complex(const LandmarkRange & landmarks, + const WitnessRange & witnesses) + : witnesses_(witnesses), landmarks_(landmarks), landmark_tree_(landmarks_) + { + } + + + /** \brief Returns the point corresponding to the given vertex. + */ + template + Point_d get_point( Vertex_handle vertex ) const + { + return landmarks_[vertex]; + } + + /** \brief Outputs the strong witness complex of relaxation 'max_alpha_square' + * in a simplicial complex data structure. + * \details The function returns true if the construction is successful and false otherwise. + * @param[out] complex Simplicial complex data structure, which is a model of + * SimplicialComplexForWitness concept. + * @param[in] max_alpha_square Maximal squared relaxation parameter. + * @param[in] limit_dimension Represents the maximal dimension of the simplicial complex + * (default value = no limit). + */ + template < typename SimplicialComplexForWitness > + bool create_complex(SimplicialComplexForWitness& complex, + FT max_alpha_square, + Landmark_id limit_dimension = std::numeric_limits::max()-1) + { + Landmark_id complex_dim = 0; + if (complex.num_vertices() > 0) { + std::cerr << "Euclidean strong witness complex cannot create complex - complex is not empty.\n"; + return false; + } + if (max_alpha_square < 0) { + std::cerr << "Euclidean strong witness complex cannot create complex - squared relaxation parameter must be non-negative.\n"; + return false; + } + if (limit_dimension < 0) { + std::cerr << "Euclidean strong witness complex cannot create complex - limit dimension must be non-negative.\n"; + return false; + } + for (auto w: witnesses_) { + ActiveWitness aw(landmark_tree_.query_incremental_nearest_neighbors(w)); + typeVectorVertex simplex; + typename ActiveWitness::iterator aw_it = aw.begin(); + float lim_dist2 = aw.begin()->second + max_alpha_square; + while ((Landmark_id)simplex.size() < limit_dimension + 1 && aw_it != aw.end() && aw_it->second < lim_dist2) { + simplex.push_back(aw_it->first); + complex.insert_simplex_and_subfaces(simplex, aw_it->second - aw.begin()->second); + aw_it++; + } + // continue inserting limD-faces of the following simplices + typeVectorVertex& vertices = simplex; //'simplex' now will be called vertices + while (aw_it != aw.end() && aw_it->second < lim_dist2) { + typeVectorVertex facet = {}; + add_all_faces_of_dimension(limit_dimension, vertices, vertices.begin(), aw_it, aw_it->second - aw.begin()->second, facet, complex); + vertices.push_back(aw_it->first); + aw_it++; + } + if ((Landmark_id)simplex.size() - 1 > complex_dim) + complex_dim = simplex.size() - 1; + } + complex.set_dimension(complex_dim); + return true; + } + +private: + + /* \brief Adds recursively all the faces of a certain dimension dim-1 witnessed by the same witness. + * Iterator is needed to know until how far we can take landmarks to form simplexes. + * simplex is the prefix of the simplexes to insert. + * The landmark pointed by aw_it is added to all formed simplices. + */ + template < typename SimplicialComplexForWitness > + void add_all_faces_of_dimension(Landmark_id dim, + typeVectorVertex& vertices, + typename typeVectorVertex::iterator curr_it, + typename ActiveWitness::iterator aw_it, + FT filtration_value, + typeVectorVertex& simplex, + SimplicialComplexForWitness& sc) const + { + if (dim > 0) + while (curr_it != vertices.end()) { + simplex.push_back(*curr_it); + typename typeVectorVertex::iterator next_it = ++curr_it; + add_all_faces_of_dimension(dim-1, + vertices, + next_it, + aw_it, + filtration_value, + simplex, + sc); + simplex.pop_back(); + add_all_faces_of_dimension(dim, + vertices, + next_it, + aw_it, + filtration_value, + simplex, + sc); + } + else if (dim == 0) { + simplex.push_back(aw_it->first); + sc.insert_simplex_and_subfaces(simplex, filtration_value); + simplex.pop_back(); + } + } + + //@} +}; + +} // namespace witness_complex + +} // namespace Gudhi + +#endif // EUCLIDEAN_STRONG_WITNESS_COMPLEX_H_ -- cgit v1.2.3