2level.hpp

/*********************************************************************
 *
 *  Linear Arrangement Library - A library that implements a collection
 *  algorithms for linear arrangments of graphs.
 *
 *  Copyright (C) 2019 - 2021
 *
 *  This file is part of Linear Arrangement Library. To see the full code
 *  visit the webpage:
 *      https://github.com/lluisalemanypuig/linear-arrangement-library.git
 *
 *  Linear Arrangement Library is free software: you can redistribute it
 *  and/or modify it under the terms of the GNU Affero General Public License
 *  as published by the Free Software Foundation, either version 3 of the
 *  License, or (at your option) any later version.
 *
 *  Linear Arrangement Library 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 Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with Linear Arrangement Library.  If not, see <http://www.gnu.org/licenses/>.
 *
 *  Contact:
 *
 *      Lluís Alemany Puig (lalemany@cs.upc.edu)
 *          LARCA (Laboratory for Relational Algorithmics, Complexity and Learning)
 *          CQL (Complexity and Quantitative Linguistics Lab)
 *          Jordi Girona St 1-3, Campus Nord UPC, 08034 Barcelona.   CATALONIA, SPAIN
 *          Webpage: https://cqllab.upc.edu/people/lalemany/
 *
 *      Ramon Ferrer i Cancho (rferrericancho@cs.upc.edu)
 *          LARCA (Laboratory for Relational Algorithmics, Complexity and Learning)
 *          CQL (Complexity and Quantitative Linguistics Lab)
 *          Office S124, Omega building
 *          Jordi Girona St 1-3, Campus Nord UPC, 08034 Barcelona.   CATALONIA, SPAIN
 *          Webpage: https://cqllab.upc.edu/people/rferrericancho/
 *
 ********************************************************************/
 
#pragma once
 
// C++ includes
#if defined DEBUG
#include <cassert>
#endif
#include <vector>
 
// lal includes
#include <lal/definitions.hpp>
#include <lal/numeric/rational.hpp>
#include <lal/graphs/graph.hpp>
 
namespace lal {
namespace linarr {
 
/* 2-LEVEL METRICS */
 
// **DEVELOPER NOTE**
// This function's documentation has to be updated manually in the python
// interface file '.i' 'python-interface/submodules/linarr.i'
template<class G>
numeric::rational mean_dependency_distance_2level_rational
(const std::vector<G>& L, const std::vector<linear_arrangement>& P = {})
noexcept
{
    static_assert(std::is_base_of_v<graphs::graph, G>);
 
#if defined DEBUG
    // the number of graphs and number of linear arrangements
    // must coincide unless no arrangement was given.
    assert(P.size() == 0 or L.size() == P.size());
#endif
 
    numeric::rational sum_MDD(0);
    if (P.size() == 0) {
        const linear_arrangement empty_arr;
        for (size_t i = 0; i < L.size(); ++i) {
            sum_MDD += mean_dependency_distance_rational(L[i], empty_arr);
        }
    }
    else {
        for (size_t i = 0; i < L.size(); ++i) {
            sum_MDD += mean_dependency_distance_rational(L[i], P[i]);
        }
    }
    return sum_MDD/static_cast<int64_t>(L.size());
}
 
// **DEVELOPER NOTE**
// This function's documentation has to be updated manually in the python
// interface file '.i' 'python-interface/submodules/linarr.i'
template<class G>
double mean_dependency_distance_2level
(const std::vector<G>& L, const std::vector<linear_arrangement>& P = {})
noexcept
{
    return mean_dependency_distance_2level_rational(L, P).to_double();
}
 
} // -- namespace linarr
} // -- namespace lal