hypergraph.h

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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/*                                                                           */
/*                  This file is part of the program                         */
/*          GCG --- Generic Column Generation                                */
/*                  a Dantzig-Wolfe decomposition based extension            */
/*                  of the branch-cut-and-price framework                    */
/*         SCIP --- Solving Constraint Integer Programs                      */
/*                                                                           */
/* Copyright (C) 2010-2021 Operations Research, RWTH Aachen University       */
/*                         Zuse Institute Berlin (ZIB)                       */
/*                                                                           */
/* This program is free software; you can redistribute it and/or             */
/* modify it under the terms of the GNU Lesser General Public License        */
/* as published by the Free Software Foundation; either version 3            */
/* of the License, or (at your option) any later version.                    */
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/* 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 Lesser General Public License for more details.                       */
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/* You should have received a copy of the GNU Lesser General Public License  */
/* along with this program; if not, write to the Free Software               */
/* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.*/
/*                                                                           */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
 
/**@file   hypergraph.h
 * @brief  miscellaneous hypergraph methods for structure detection
 * @author Martin Bergner
 * @author Annika Thome
 */
 
/*---+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/
 
 
 
#ifndef GCG_HYPERGRAPH_H_
#define GCG_HYPERGRAPH_H_
#include "objscip/objscip.h"
#include "tclique/tclique.h"
#include "weights.h"
#include "pub_decomp.h"
#include "graph.h"
#include "graph_interface.h"
 
#include <exception>
#include <vector>
#include <string>
 
namespace gcg {
 
template <class T>
class Hypergraph : public GraphInterface {
public:
   std::string name;
protected:
   SCIP* scip_;
   Graph<T>* graph;
   std::vector<int> nodes;
   std::vector<int> hedges;
   std::vector<int> mapping;
   int lastnode;
   int dummynodes;
 
public:
   /** Constructor */
   Hypergraph(
      SCIP*                 scip
   );
 
   void swap(Hypergraph & other) // the swap member function (should never fail!)
   {
      // swap all the members (and base subobject, if applicable) with other
      std::swap(partition, other.partition);
      std::swap(scip_ , other.scip_);
      std::swap(graph , other.graph);
      std::swap(hedges , other.hedges);
      std::swap(nodes , other.nodes);
      std::swap(lastnode, other.lastnode);
      std::swap(dummynodes, other.dummynodes);
   }
 
   Hypergraph& operator=(Hypergraph other) // note: argument passed by value!
   {
      // swap this with other
      swap(other);
 
      return *this;
   }
 
   /** Destruktor */
   ~Hypergraph();
 
   /** adds the node with the given weight to the graph */
   SCIP_RETCODE addNode(int i,int weight);
 
   /** adds the edge to the graph */
   SCIP_RETCODE addHyperedge(std::vector<int> &edge, int weight);
 
   /** adds the edge to the graph */
   SCIP_RETCODE addNodeToHyperedge(int node, int hedge);
 
   /** return the number of nodes */
   int getNNodes();
 
   /** return the number of edges (or hyperedges) */
   int getNHyperedges();
 
   /** return the number of neighbor nodes of given node */
   int getNNeighbors(
      int                i                   /**< the given node */
      );
 
   /** return the neighboring nodes of a given node */
   std::vector<int> getNeighbors(
      int                i                   /**< the given node */
      );
 
   /** return the nodes spanned by hyperedge */
   std::vector<int> getHyperedgeNodes(
      int i
      );
 
   /** return the number of nodes spanned by hyperedge */
   int getNHyperedgeNodes(
      int i
      );
 
   /** assigns partition to a given node*/
   void setPartition(int i, int ID);
 
   /** writes the hypergraph to the given file.
    *  The format is hypergraph dependent
    */
   SCIP_RETCODE writeToFile(
      int                fd,                  /**< filename where the graph should be written to */
      SCIP_Bool          writeweights        /**< whether to write weights */
    );
 
   /**
    * reads the partition from the given file.
    * The format is hypergraph dependent. The default is a file with one line for each node a
    */
   SCIP_RETCODE readPartition(
      const char*        filename            /**< filename where the partition is stored */
   );
 
   /** return the weight of given node */
   int getWeight(
      int                i                   /**< the given node */
      );
 
   /** return the weight of given hyperedge */
   int getHyperedgeWeight(
      int                i                   /**< the given hyperedge */
      );
 
   /** set the number of dummy nodes */
   void setDummynodes(int dummynodes_)
   {
      dummynodes = dummynodes_;
   }
 
 
   int getDummynodes() const
   {
      return dummynodes;
   }
 
   SCIP_RETCODE flush();
private:
   int computeNodeId(int i);
};
 
}
 
#endif