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Diffstat (limited to 'src/Skeleton_blocker/include/gudhi/Skeleton_blocker/Skeleton_blocker_sub_complex.h')
| -rw-r--r-- | src/Skeleton_blocker/include/gudhi/Skeleton_blocker/Skeleton_blocker_sub_complex.h | 261 |
1 files changed, 261 insertions, 0 deletions
diff --git a/src/Skeleton_blocker/include/gudhi/Skeleton_blocker/Skeleton_blocker_sub_complex.h b/src/Skeleton_blocker/include/gudhi/Skeleton_blocker/Skeleton_blocker_sub_complex.h new file mode 100644 index 00000000..4c48ff31 --- /dev/null +++ b/src/Skeleton_blocker/include/gudhi/Skeleton_blocker/Skeleton_blocker_sub_complex.h @@ -0,0 +1,261 @@ +/* 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): David Salinas + * + * Copyright (C) 2014 Inria + * + * Modification(s): + * - YYYY/MM Author: Description of the modification + */ + +#ifndef SKELETON_BLOCKER_SKELETON_BLOCKER_SUB_COMPLEX_H_ +#define SKELETON_BLOCKER_SKELETON_BLOCKER_SUB_COMPLEX_H_ + +#include <gudhi/Skeleton_blocker_complex.h> +#include <gudhi/Skeleton_blocker/Skeleton_blocker_simplex.h> +#include <gudhi/Debug_utils.h> + +#include <map> +#include <vector> + +namespace Gudhi { + +namespace skeleton_blocker { + +/** + * @brief Simplicial subcomplex of a complex represented by a skeleton/blockers pair. + * @extends Skeleton_blocker_complex + * @details Stores a subcomplex of a simplicial complex. + * To simplify explanations below, we will suppose that : + * - K is the root simplicial complex + * - L is a subcomplex of K. + * + * One vertex of K may exists in L but with a different address. + * To be able to locate the vertices in K from vertices of L, the class + * stores a map 'adresses' between vertices of K and vertices of L. + * + * Note that the type for handle of vertices of L is 'Vertex_handle' and + * the type for handle of vertices of K is 'Root_vertex_handle'. + * + * The template ComplexType is type of the root complex. It allows to know + * if the subcomplex is geometric or not. + * It has to be either 'Skeleton_blockers_complex' or 'Skeleton_blockers_geometric_complex'. + * + */ +template<typename ComplexType> +class Skeleton_blocker_sub_complex : public ComplexType { + protected: + template<class T> friend class Skeleton_blocker_link_complex; + + typedef typename ComplexType::Graph Graph; + typedef typename ComplexType::Edge_handle Edge_handle; + + typedef typename ComplexType::boost_vertex_handle boost_vertex_handle; + + public: + using ComplexType::add_vertex; + using ComplexType::add_edge_without_blockers; + using ComplexType::add_blocker; + + typedef typename ComplexType::Vertex_handle Vertex_handle; + typedef typename ComplexType::Root_vertex_handle Root_vertex_handle; + typedef typename ComplexType::Simplex Simplex; + typedef typename ComplexType::Root_simplex_handle Root_simplex_handle; + + protected: + /** + * @brief Determines whether all proper faces of simplex 'sigma' belong to 'link1' \cup 'link2' + * where 'link1' and 'link2' are subcomplexes of the same complex of type ComplexType + */ + typedef std::map<Root_vertex_handle, Vertex_handle> IdAddressMap; + typedef typename IdAddressMap::value_type AddressPair; + typedef typename IdAddressMap::iterator IdAddressMapIterator; + typedef typename IdAddressMap::const_iterator IdAddressMapConstIterator; + std::map<Root_vertex_handle, Vertex_handle> adresses; + + public: + /** + * Add a vertex 'global' of K to L. When added to L, this vertex will receive + * another number, addresses(global), its local adress. + * return the adress where the vertex lay on L. + * The vertex corresponding to 'global' must not be already present + * in the complex. + */ + Vertex_handle add_vertex(Root_vertex_handle global) { + assert(!this->contains_vertex(global)); + Vertex_handle address(boost::add_vertex(this->skeleton)); + this->num_vertices_++; + (*this)[address].activate(); + (*this)[address].set_id(global); + adresses.insert(AddressPair(global, address)); + this->degree_.push_back(0); + return address; + } + + /** + * Add an edge (v1_root,v2_root) to the sub-complex. + * It assumes that both vertices corresponding to v1_root and v2_root are present + * in the sub-complex. + */ + void add_edge_without_blockers(Root_vertex_handle v1_root, Root_vertex_handle v2_root) { + auto v1_sub(this->get_address(v1_root)); + auto v2_sub(this->get_address(v2_root)); + assert(v1_sub && v2_sub); + this->ComplexType::add_edge_without_blockers(*v1_sub, *v2_sub); + } + + /** + * Add a blocker to the sub-complex. + * It assumes that all vertices of blocker_root are present + * in the sub-complex. + */ + void add_blocker(const Root_simplex_handle& blocker_root) { + auto blocker_sub = this->get_address(blocker_root); + assert(blocker_sub); + this->add_blocker(new Simplex(*blocker_sub)); + } + + public: + /** + * Constructs the restricted complex of 'parent_complex' to + * vertices of 'simplex'. + */ + void make_restricted_complex(const ComplexType & parent_complex, + const Simplex& simplex) { + this->clear(); + // add vertices to the sub complex + for (auto x : simplex) { + assert(parent_complex.contains_vertex(x)); + auto x_local = this->add_vertex(parent_complex[x].get_id()); + (*this)[x_local] = parent_complex[x]; + } + + // add edges to the sub complex + for (auto x : simplex) { + // x_neigh is the neighbor of x intersected with vertices_simplex + Simplex x_neigh; + parent_complex.add_neighbours(x, x_neigh, true); + x_neigh.intersection(simplex); + for (auto y : x_neigh) { + this->add_edge_without_blockers(parent_complex[x].get_id(), parent_complex[y].get_id()); + } + } + + // add blockers to the sub complex + for (auto blocker : parent_complex.const_blocker_range()) { + // check if it is the first time we encounter the blocker + if (simplex.contains(*blocker)) { + Root_simplex_handle blocker_root(parent_complex.get_id(*(blocker))); + Simplex blocker_restr( + *(this->get_simplex_address(blocker_root))); + this->add_blocker(new Simplex(blocker_restr)); + } + } + } + + void clear() { + adresses.clear(); + ComplexType::clear(); + } + + /** + * Compute the local vertex in L corresponding to the vertex global in K. + * runs in O(log n) if n = num_vertices() + */ + boost::optional<Vertex_handle> get_address(Root_vertex_handle global) const { + boost::optional < Vertex_handle > res; + IdAddressMapConstIterator it = adresses.find(global); + if (it == adresses.end()) + res.reset(); + else + res = (*it).second; + return res; + } + + // /** + // * Allocates a simplex in L corresponding to the simplex s in K + // * with its local adresses and returns an AddressSimplex. + // */ + // boost::optional<Simplex> get_address(const Root_simplex_handle & s) const; + + // private: + /** + * same as get_address except that it will return a simplex in any case. + * The vertices that were not found are not added. + */ + // @remark should be private but problem with VS + + std::vector<boost::optional<Vertex_handle> > get_addresses( + const Root_simplex_handle & s) const { + std::vector < boost::optional<Vertex_handle> > res; + for (auto i : s) { + res.push_back(get_address(i)); + } + return res; + } +}; + +/** + * @remark remarque perte de temps a creer un nouveau simplexe a chaque fois + * alors qu'on pourrait utiliser a la place de 'addresses_sigma_in_link' + * un simplex avec des valeurs sp�ciales ComplexDS::null_vertex par exemple + * pour indiquer qu'un vertex n'appartient pas au complex + */ +template<typename ComplexType> +bool proper_face_in_union( + Skeleton_blocker_sub_complex<ComplexType> & link, + std::vector<boost::optional<typename ComplexType::Vertex_handle> > & addresses_sigma_in_link, + std::size_t vertex_to_be_ignored) { + // we test that all vertices of 'addresses_sigma_in_link' but 'vertex_to_be_ignored' + // are in link1 if it is the case we construct the corresponding simplex + bool vertices_sigma_are_in_link = true; + typename ComplexType::Simplex sigma_in_link; + for (std::size_t i = 0; i < addresses_sigma_in_link.size(); ++i) { + if (i != vertex_to_be_ignored) { + if (!addresses_sigma_in_link[i]) { + vertices_sigma_are_in_link = false; + break; + } else { + sigma_in_link.add_vertex(*addresses_sigma_in_link[i]); + } + } + } + // If one of vertices of the simplex is not in the complex then it returns false + // Otherwise, it tests if the simplex is in the complex + return vertices_sigma_are_in_link && link.contains(sigma_in_link); +} + +// Remark: this function should be friend in order to leave get_adresses private +// however doing so seemes currently not possible due to a visual studio bug c2668 +// "the compiler does not support partial ordering of template functions as specified in the C++ Standard" +// http://www.serkey.com/error-c2668-ambiguous-call-to-overloaded-function-bb45ft.html + +template<typename ComplexType> +bool proper_faces_in_union( + Skeleton_blocker_simplex<typename ComplexType::Root_vertex_handle> & sigma, + Skeleton_blocker_sub_complex<ComplexType> & link1, + Skeleton_blocker_sub_complex<ComplexType> & link2) { + typedef typename ComplexType::Vertex_handle Vertex_handle; + std::vector < boost::optional<Vertex_handle> > addresses_sigma_in_link1 = + link1.get_addresses(sigma); + std::vector < boost::optional<Vertex_handle> > addresses_sigma_in_link2 = + link2.get_addresses(sigma); + + for (std::size_t current_index = 0; current_index < addresses_sigma_in_link1.size(); + ++current_index) { + if (!proper_face_in_union(link1, addresses_sigma_in_link1, current_index) + && !proper_face_in_union(link2, addresses_sigma_in_link2, + current_index)) { + return false; + } + } + return true; +} + +} // namespace skeleton_blocker + +namespace skbl = skeleton_blocker; + +} // namespace Gudhi + +#endif // SKELETON_BLOCKER_SKELETON_BLOCKER_SUB_COMPLEX_H_ |