paradiseo/branches/paradiseo-peo-meta-model/src/peoSyncMultiStart.h

// "peoSyncMultiStart.h"

// (c) OPAC Team, LIFL, August 2005

/* 
   Contact: paradiseo-help@lists.gforge.inria.fr
*/

#ifndef __peoSyncMultiStart_h
#define __peoSyncMultiStart_h

#include <utils/eoUpdater.h>
#include <moAlgo.h>

#include <eoSelect.h>
#include <eoReplacement.h>
#include <eoContinue.h>

#include "core/service.h"
#include "core/messaging.h"
#include "core/peo_debug.h"


extern int getNodeRank();


//! Class providing the basis for the synchronous multi-start model.

//! The peoSyncMultiStart class provides the basis for implementing the synchronous multi-start model,
//! for launching several solution-based algorithms in parallel on a specified initial population. As a simple
//! example, several hill climbing algorithms may be synchronously launched on the specified population, each
//! algorithm acting upon one individual only, the final result being integrated back in the population. A
//! peoSyncMultiStart object can be specified as checkpoint object for a classic ParadisEO evolutionary algorithm
//! thus allowing for simple hybridization schemes which combine the evolutionary approach with a local search approach,
//! for example, executed at the end of each generation.
template< class EOT > class peoSyncMultiStart : public Service, public eoUpdater {

public:

	//! Constructor function - several simple parameters are required for defining the characteristics of the multi-start model.
	//!
	//! @param eoContinue< EOT >& __cont - defined for including further functionality - no semantics associated at this time;
	//! @param eoSelect< EOT >& __select - selection strategy for obtaining a subset of the initial population on which to apply the specified algorithm;
	//! @param eoReplacement< EOT >& __replace - replacement strategy for integrating the resulting individuals in the initial population;
	//! @param moAlgo< EOT >& __ls - algorithm to be applied on each of the selected individuals - a <b>moAlgo< EOT ></b>-derived object must be specified;
	//! @param eoPop< EOT >& __pop - the initial population from which the individuals are selected for applying the specified algorithm.
	peoSyncMultiStart( 

				eoContinue< EOT >& __cont,
				eoSelect< EOT >& __select,
				eoReplacement< EOT >& __replace,
				moAlgo< EOT >& __ls, 
				eoPop< EOT >& __pop 
		);

	//! Operator which synchronously executes the specified	algorithm on the individuals selected from the initial population.
	//! There is no need to explicitly call the operator - automatically called as checkpoint operator.
	void operator()();

	//! Auxiliary function for transferring data between the process requesting the synchronous execution of the specified
	//! algorithm and the process which actually executes the algorithm. There is no need to explicitly call the function.
	void packData();

	//! Auxiliary function for transferring data between the process requesting the synchronous execution of the specified
	//! algorithm and the process which actually executes the algorithm. There is no need to explicitly call the function.
	void unpackData();

	//! Auxiliary function for actually executing the specified algorithm on one assigned individual. There is no need to 
	//! explicitly call the function.
	void execute();

	//! Auxiliary function for transferring data between the process requesting the synchronous execution of the specified
	//! algorithm and the process which actually executes the algorithm. There is no need to explicitly call the function.
	void packResult();

	//! Auxiliary function for transferring data between the process requesting the synchronous execution of the specified
	//! algorithm and the process which actually executes the algorithm. There is no need to explicitly call the function.
	void unpackResult();

	//! Auxiliary function for notifications between the process requesting the synchronous multi-start execution
	//! and the processes that performs the actual execution phase. There is no need to explicitly call the function.
	void notifySendingData();

	//! Auxiliary function for notifications between the process requesting the synchronous multi-start execution
	//! and the processes that performs the actual execution phase. There is no need to explicitly call the function.
	void notifySendingAllResourceRequests();

private:

	eoContinue< EOT >& cont;
	eoSelect< EOT >& select;
	eoReplacement< EOT >& replace;

	moAlgo< EOT >& ls;

	eoPop< EOT >& pop;
	eoPop< EOT > sel;
	eoPop< EOT > impr_sel;

	EOT sol;
	unsigned idx;
	unsigned num_term;
};


template< class EOT > peoSyncMultiStart< EOT > :: peoSyncMultiStart( 

				eoContinue < EOT >& __cont, 
				eoSelect< EOT >& __select,
				eoReplacement< EOT >& __replace, 
				moAlgo < EOT >& __ls,
				eoPop< EOT >& __pop 

		) : cont( __cont ), select( __select ), replace( __replace ), ls( __ls ), pop( __pop )
{

}


template< class EOT > void peoSyncMultiStart< EOT > :: packData() {

	 :: pack( sel[ idx++ ] );
}


template< class EOT > void peoSyncMultiStart< EOT > :: unpackData() {

	unpack( sol );
}


template< class EOT > void peoSyncMultiStart< EOT > :: execute() {

	ls( sol );
}


template< class EOT > void peoSyncMultiStart< EOT > :: packResult() {

	pack( sol );
}


template< class EOT > void peoSyncMultiStart< EOT > :: unpackResult() {

	unpack( sol );
	impr_sel.push_back( sol );
	num_term++;

	if ( num_term == sel.size() ) {

		getOwner()->setActive();
		replace( pop, impr_sel );

		printDebugMessage( "replacing the improved individuals in the population." );
		resume();
	}
}


template< class EOT > void peoSyncMultiStart< EOT > :: operator()() {

	printDebugMessage( "performing the parallel multi-start hybridization." );
	select( pop, sel );
	impr_sel.clear();
	idx = num_term = 0;
	requestResourceRequest( sel.size() );
	stop();
}


template< class EOT > void peoSyncMultiStart< EOT > :: notifySendingData() {

}


template< class EOT > void peoSyncMultiStart< EOT > :: notifySendingAllResourceRequests() {

	getOwner()->setPassive();
}


#endif