/*

     This file is part of Combean.

     Combean 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 2 of the License, or

     (at your option) any later version.

     Combean 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 Combean; if not, write to the Free Software

     Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

 */

 /*

  * Created on 30.08.2005

  *

  */

 package net.sourceforge.combean.graph.alg.lp;

 import net.sourceforge.combean.interfaces.graph.Edge;

 import net.sourceforge.combean.interfaces.graph.containers.doubleval.FixedDoubleEdgeMap;

 import net.sourceforge.combean.interfaces.graph.prop.GlobalNumberedEdgesGraphProp;

 import net.sourceforge.combean.interfaces.mathprog.lp.model.LPModelSolver;

 import net.sourceforge.combean.mathprog.lp.model.LPModelIndexImpl;

 /**

  * Wrap a LP model modelSolver as fixed double edge map, which returns the primal

  * solution value for each edge.

  * 

  * This is useful for LPs where a part of the variables correspond to settings

  * for the edges in a graph.

  * 

  * @author schickin

  *

  */

 public class LPModelSolverAsFixedDoubleEdgeMap implements FixedDoubleEdgeMap {

     private LPModelSolver modelSolver = null;

     private GlobalNumberedEdgesGraphProp numberedEdges = null;

     private String offsetId = null;

     /**

      * Constructor

      * 

      * @param solver the LP model modelSolver to be wrapped. The LP model must

      * contain the edges of the graph for which the edge map is accessed.

      * @param numberedEdges the graph to which the edge map refers.

      * @param offsetId the offset identifier for the columns in the LP model

      * which correspond to the edges in the given graph.

      */

     public LPModelSolverAsFixedDoubleEdgeMap(LPModelSolver solver,

             GlobalNumberedEdgesGraphProp numberedEdges,

             String offsetId) {

         super();

         this.modelSolver = solver;

         this.numberedEdges = numberedEdges;

         this.offsetId = offsetId;

     }

     /* (non-Javadoc)

      * @see net.sourceforge.combean.interfaces.graph.containers.doubleval.FixedDoubleEdgeMap#getDouble(net.sourceforge.combean.interfaces.graph.Edge)

      */

     public double getDouble(Edge e) {

          return this.modelSolver.getSolution(

                  new LPModelIndexImpl(

                          this.numberedEdges.getEdgeNumber(e), this.offsetId));

     }

 }