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Diffstat (limited to 'src/Persistent_cohomology/concept/FilteredComplex.h')
-rw-r--r-- | src/Persistent_cohomology/concept/FilteredComplex.h | 131 |
1 files changed, 131 insertions, 0 deletions
diff --git a/src/Persistent_cohomology/concept/FilteredComplex.h b/src/Persistent_cohomology/concept/FilteredComplex.h new file mode 100644 index 00000000..26ac7ac8 --- /dev/null +++ b/src/Persistent_cohomology/concept/FilteredComplex.h @@ -0,0 +1,131 @@ +/* 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): Clément Maria + * + * Copyright (C) 2014 Inria + * + * Modification(s): + * - YYYY/MM Author: Description of the modification + */ + +/** \brief The concept FilteredComplex describes the requirements + * for a type to implement a filtered cell complex, from which + * one can compute persistent homology via a model of the concept + * PersistentHomology. + */ +struct FilteredComplex +{ +/** \brief Handle to specify a simplex. */ + typedef unspecified Simplex_handle; +/** \brief Type for the value of the filtration function. + * + * Must be comparable with <. */ + typedef unspecified Filtration_value; + +/** \brief Specifies the nature of the indexing scheme. + * + * is model of IndexingTag. */ + typedef unspecified Indexing_tag; + +/** \brief Returns a Simplex_handle that is different from all simplex handles of the simplices. */ + Simplex_handle null_simplex(); +/** \brief Returns the number of simplices in the complex. + * + * Does not count the empty simplex. */ + size_t num_simplices(); +/** \brief Returns the dimension of a simplex. */ + int dimension(Simplex_handle sh); +/** \brief Returns the filtration value of a simplex. + * + * If sh is null_simplex(), returns the maximal value of the + * filtration function on the complex. */ + Filtration_value filtration(Simplex_handle sh); + +/** \brief Returns the simplex that has index idx in the filtration. + * + * This is only called on valid indices. */ + Simplex_handle simplex ( size_t idx ); +/** \brief Iterator on the simplices belonging to the boundary of a simplex. + * + * <CODE>value_type</CODE> must be 'Simplex_handle'. + */ +typedef unspecified Boundary_simplex_iterator; +/** \brief Range giving access to the simplices in the boundary of a simplex. + * + * .begin() and .end() return type Boundary_simplex_iterator. + */ +typedef unspecified Boundary_simplex_range; + +/** \brief Returns a range giving access to all simplices of the boundary of a simplex, i.e. the set of codimension 1 + * subsimplices of the Simplex. + * + * If the simplex is \f$[v_0, \cdots ,v_d]\f$, with canonical orientation + * induced by \f$ v_0 < \cdots < v_d \f$, the iterator enumerates the + * simplices of the boundary in the order: + * \f$[v_0,\cdots,\widehat{v_i},\cdots,v_d]\f$ for \f$i\f$ from 0 to d + * + * We note that the alternate sum of the simplices given by the iterator + * gives the chains corresponding to the boundary of the simplex.*/ +Boundary_simplex_range boundary_simplex_range(Simplex_handle sh); + +/** \brief Iterator over all simplices of the complex in the order of the indexing scheme. + * + * 'value_type' must be 'Simplex_handle'. + */ +typedef unspecified Filtration_simplex_iterator; +/** \brief Range over the simplices of the complex in the order of the filtration. + * + * .begin() and .end() return type Filtration_simplex_iterator.*/ +typedef unspecified Filtration_simplex_range; +/** \brief Returns a range over the simplices of the complex in the order of the filtration. + * + * .begin() and .end() return type Filtration_simplex_iterator.*/ +Filtration_simplex_range filtration_simplex_range(); + +/** \name Map interface + * Conceptually a `std::unordered_map<Simplex_handle,std::size_t>`. + * @{ */ +/** \brief Data stored for each simplex. + * + * Must be an integer type. */ + typedef unspecified Simplex_key; +/** \brief Returns a constant dummy number that is either negative, + * or at least as large as `num_simplices()`. Suggested value: -1. */ + Simplex_key null_key (); +/** \brief Returns the number stored for a simplex by `assign_key`. + * + * This is never called on null_simplex(). */ + Simplex_key key ( Simplex_handle sh ); +/** \brief Store a number for a simplex, which can later be retrieved with `key(sh)`. + * + * This is never called on null_simplex(). */ + void assign_key(Simplex_handle sh, Simplex_key n); +/** @} */ + + +/* \brief Iterator over the simplices of the complex, + * in an arbitrary order. + * + * 'value_type' must be 'Simplex_handle'.*/ +//typedef unspecified Complex_simplex_iterator; +//typedef unspecified Complex_simplex_range; + +/* +* Returns a range over all the simplices of a +* complex. +*/ +//Complex_simplex_range complex_simplex_range(); + +/*************************************************/ /** +* @details Compares the filtration values of simplices s and t +* +* @return -1 if s comes before t in the filtration, +1 +* if it comes later, and 0 if they come at the same time +* +* @note OPTIONAL +* @todo use an enum? Just a bool? +*/ +//int is_before_in_filtration(Simplex_handle s, Simplex_handle t); +/*************************************************/ + +}; |