event_newsol.c

Go to the documentation of this file.

/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
/*                                                                           */
/*                  This file is part of the program and library             */
/*         SCIP --- Solving Constraint Integer Programs                      */
/*                                                                           */
/*  Copyright (c) 2002-2023 Zuse Institute Berlin (ZIB)                      */
/*                                                                           */
/*  Licensed under the Apache License, Version 2.0 (the "License");          */
/*  you may not use this file except in compliance with the License.         */
/*  You may obtain a copy of the License at                                  */
/*                                                                           */
/*      http://www.apache.org/licenses/LICENSE-2.0                           */
/*                                                                           */
/*  Unless required by applicable law or agreed to in writing, software      */
/*  distributed under the License is distributed on an "AS IS" BASIS,        */
/*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */
/*  See the License for the specific language governing permissions and      */
/*  limitations under the License.                                           */
/*                                                                           */
/*  You should have received a copy of the Apache-2.0 license                */
/*  along with SCIP; see the file LICENSE. If not visit scipopt.org.         */
/*                                                                           */
/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */

/**@file   event_newsol.c
 * @brief  eventhdlr that adds new solutions to the candidate pool for the exchange heuristic
 * @author Leon Eifler
 */

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

#include <assert.h>
#include <string.h>

#include "event_newsol.h"
#include "heur_cyckerlin.h"
#include "probdata_cyc.h"

#define EVENTHDLR_NAME         "newsol"
#define EVENTHDLR_DESC         "event handler for solution events"

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

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

   return SCIP_OKAY;
}

/** initialization method of event handler (called after problem was transformed) */
static
SCIP_DECL_EVENTINIT(eventInitNewsol)
{  /*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(eventExitNewsol)
{  /*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(eventExecNewsol)
{  /*lint --e{715}*/
   SCIP_SOL* newsol;

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

   if( SCIPgetStage(scip) != SCIP_STAGE_SOLVING )
      return SCIP_OKAY;

   SCIPdebugMsg(scip, "exec method of event handler for newsol solution found\n");

   newsol = SCIPeventGetSol(event);
   assert(newsol != NULL);

   SCIPdebugMsg(scip, "catch event for solution %p with obj=%g.\n", (void*) newsol, SCIPgetSolOrigObj(scip, newsol));

   SCIP_CALL( addCandSolCyckerlin(scip, newsol) );

   return SCIP_OKAY;
}

/** includes event handler for best solution found */
SCIP_RETCODE SCIPincludeEventHdlrNewsol(
   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,
      eventExecNewsol, eventhdlrdata) );

   assert(eventhdlr != NULL);

   SCIP_CALL( SCIPsetEventhdlrCopy(scip, eventhdlr, eventCopyNewsol) );
   SCIP_CALL( SCIPsetEventhdlrInit(scip, eventhdlr, eventInitNewsol) );
   SCIP_CALL( SCIPsetEventhdlrExit(scip, eventhdlr, eventExitNewsol) );

   return SCIP_OKAY;
}