event_bestsol.c

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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/*                                                                           */
/*                  This file is part of the program and library             */
/*         SCIP --- Solving Constraint Integer Programs                      */
/*                                                                           */
/*    Copyright (C) 2002-2015 Konrad-Zuse-Zentrum                            */
/*                            fuer Informationstechnik Berlin                */
/*                                                                           */
/*  SCIP is distributed under the terms of the ZIB Academic License.         */
/*                                                                           */
/*  You should have received a copy of the ZIB Academic License              */
/*  along with SCIP; see the file COPYING. If not email to scip@zib.de.      */
/*                                                                           */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/**@file   event_bestsol.c
 * @brief  eventhdlr for best solution found
 * @author Gerald Gamrath
 * @author Daniel Rehfeldt
 *
 * Event handler for printing DIMACS solution file.
 */

/*--+----1----+----2----+----3----+----4----+----5----+----6----+----7----+----8----+----9----+----0----+----1----+----2*/

#include "event_bestsol.h"
#include "probdata_stp.h"
#include "grph.h"

#include <string.h>

#define EVENTHDLR_NAME         "bestsol"
#define EVENTHDLR_DESC         "event handler for best solutions found"

/** copy method for event handler plugins (called when SCIP copies plugins) */
static
SCIP_DECL_EVENTCOPY(eventCopyBestsol)
{  /*lint --e{715}*/
   assert(scip != NULL);
   assert(eventhdlr != NULL);
   assert(strcmp(SCIPeventhdlrGetName(eventhdlr), EVENTHDLR_NAME) == 0);

   /* call inclusion method of event handler */
   SCIP_CALL( SCIPincludeEventHdlrBestsol(scip) );

   return SCIP_OKAY;
}

/** initialization method of event handler (called after problem was transformed) */
static
SCIP_DECL_EVENTINIT(eventInitBestsol)
{  /*lint --e{715}*/
   assert(scip != NULL);
   assert(eventhdlr != NULL);
   assert(strcmp(SCIPeventhdlrGetName(eventhdlr), EVENTHDLR_NAME) == 0);

   /* notify SCIP that your event handler wants to react on the event type best solution found */
   SCIP_CALL( SCIPcatchEvent( scip, SCIP_EVENTTYPE_BESTSOLFOUND, eventhdlr, NULL, NULL) );

   return SCIP_OKAY;
}

/** deinitialization method of event handler (called before transformed problem is freed) */
static
SCIP_DECL_EVENTEXIT(eventExitBestsol)
{  /*lint --e{715}*/
   assert(scip != NULL);
   assert(eventhdlr != NULL);
   assert(strcmp(SCIPeventhdlrGetName(eventhdlr), EVENTHDLR_NAME) == 0);

   /* notify SCIP that your event handler wants to drop the event type best solution found */
   SCIP_CALL( SCIPdropEvent( scip, SCIP_EVENTTYPE_BESTSOLFOUND, eventhdlr, NULL, -1) );

   return SCIP_OKAY;
}

/** execution method of event handler */
static
SCIP_DECL_EVENTEXEC(eventExecBestsol)
{  /*lint --e{715}*/
   SCIP_SOL* bestsol;
   SCIP_Real solvalue;
   SCIP_Real factor = 1.0;

   if( SCIPprobdataGetType(scip) == STP_MAX_NODE_WEIGHT )
      factor = -1.0;

   assert(eventhdlr != NULL);
   assert(strcmp(SCIPeventhdlrGetName(eventhdlr), EVENTHDLR_NAME) == 0);
   assert(event != NULL);
   assert(scip != NULL);
   assert(SCIPeventGetType(event) == SCIP_EVENTTYPE_BESTSOLFOUND);

   SCIPdebugMessage("exec method of event handler for best solution found\n");

   bestsol = SCIPgetBestSol(scip);
   assert(bestsol != NULL);
   solvalue = factor * SCIPgetSolOrigObj(scip, bestsol);

   SCIPprobdataWriteLogLine(scip, "Solution %.1f %16.9g\n", SCIPgetTotalTime(scip), solvalue);

   SCIP_CALL( SCIPprobdataWriteIntermediateSolution(scip) );

#if 0
   /* perform bound-based reduction tests to fix variables */
   if( SCIPprobdataGetType(scip) == STP_HOP_CONS )
   {
      SCIP_PROBDATA* probdata;
      GRAPH* g;
      PATH* vnoi;
      SCIP_Real*  cost;
      SCIP_Real*  radius;
      SCIP_Real*  costrev;
      SCIP_Real primalobj;
      SCIP_Real offset;
      int*    heap;
      int*    state;
      int*    vbase;
      int*    pathedge;
      int nnodes;
      int nedges;
      int     hcrcnelims;

      /* get problem data */
      probdata = SCIPgetProbData(scip);
      assert(probdata != NULL);

      /* get graph */
      g = SCIPprobdataGetGraph(probdata);
      assert(g != NULL);
      assert(g->stp_type == STP_HOP_CONS);

      offset = SCIPprobdataGetOffset(scip);
      primalobj = SCIPgetPrimalbound(scip);
      nnodes = g->knots;
      nedges = g->edges;

      /* allocate memory */
      SCIP_CALL( SCIPallocBufferArray(scip, &heap, nnodes + 1) );
      SCIP_CALL( SCIPallocBufferArray(scip, &state, nnodes) );
      SCIP_CALL( SCIPallocBufferArray(scip, &cost, nedges) );
      SCIP_CALL( SCIPallocBufferArray(scip, &radius, nnodes) );
      SCIP_CALL( SCIPallocBufferArray(scip, &costrev, nedges) );
      SCIP_CALL( SCIPallocBufferArray(scip, &vbase, nnodes) );
      SCIP_CALL( SCIPallocBufferArray(scip, &pathedge, nnodes) );
      SCIP_CALL( SCIPallocBufferArray(scip, &vnoi, nnodes) );

      printf("perfrom HC %f\n", offset);
      SCIP_CALL( hcrcbound_reduce(scip, g, vnoi, cost, costrev, radius, offset, primalobj, heap, state, vbase, &hcrcnelims, pathedge, TRUE) );

      /* free memory */
      SCIPfreeBufferArray(scip, &vnoi);
      SCIPfreeBufferArray(scip, &pathedge);
      SCIPfreeBufferArray(scip, &vbase);
      SCIPfreeBufferArray(scip, &costrev);
      SCIPfreeBufferArray(scip, &radius);
      SCIPfreeBufferArray(scip, &cost);
      SCIPfreeBufferArray(scip, &state);
      SCIPfreeBufferArray(scip, &heap);
   }
#endif
   return SCIP_OKAY;
}

/** includes event handler for best solution found */
SCIP_RETCODE SCIPincludeEventHdlrBestsol(
   SCIP*                 scip                /**< SCIP data structure */
   )
{
   SCIP_EVENTHDLRDATA* eventhdlrdata;
   SCIP_EVENTHDLR* eventhdlr;
   eventhdlrdata = NULL;

   eventhdlr = NULL;
   /* create event handler for events on watched variables */
   SCIP_CALL( SCIPincludeEventhdlrBasic(scip, &eventhdlr, EVENTHDLR_NAME, EVENTHDLR_DESC, eventExecBestsol, eventhdlrdata) );
   assert(eventhdlr != NULL);

   SCIP_CALL( SCIPsetEventhdlrCopy(scip, eventhdlr, eventCopyBestsol) );
   SCIP_CALL( SCIPsetEventhdlrInit(scip, eventhdlr, eventInitBestsol) );
   SCIP_CALL( SCIPsetEventhdlrExit(scip, eventhdlr, eventExitBestsol) );

   return SCIP_OKAY;
}