event_bestsol.c

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/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/*                                                                           */
/*                  This file is part of the program and library             */
/*         SCIP --- Solving Constraint Integer Programs                      */
/*                                                                           */
/*    Copyright (C) 2002-2019 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 visit scip.zib.de.         */
/*                                                                           */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/**@file   examples/Eventhdlr/src/event_bestsol.c
 * @brief  eventhdlr for best solution found
 * @author Stefan Heinz
 * @author Michael Winkler
 */

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

#include "event_bestsol.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;

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

   SCIPdebugMsg(scip, "exec method of event handler for best solution found\n");
   
   bestsol = SCIPgetBestSol(scip);
   assert(bestsol != NULL);
   solvalue = SCIPgetSolOrigObj(scip, bestsol);
   
   /* print best solution value */
   SCIPinfoMessage(scip, NULL, "found new best solution with solution value <%g> in SCIP <%s>\n", 
      solvalue, SCIPgetProbName(scip) );
   
   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;
}