[gecode-users] Reducing a view domain during propagation

[Martin Mann]

Hi Amina,

years back I wrote the attached std::set range iterator. you can use it 
with any of the IntView shrink function members like narrow etc. 
something like

////////////
   // setup iterator
GC_StlSetRangeIterator supportIter(&support);
   // prune the domain to supported values
GECODE_ME_CHECK(x0.narrow_r(home, supportIter, false));
////////////

the iterator implementation is obviously not the nices nor best source 
code possible but might be a starting point.. as I said, wrote it years 
ago and didnt touched it since that time.

Hope it helps.
Best,
Martin



Am 19.06.2013 20:00, schrieb Christian Schulte:
> Read Chapter 25 in MPG and then you will have to implement a Gecode-style
> iterator that iterates over the values of set<int>.
>
>
>
> Best
>
> Christian
>
>
>
> --
>
> Christian Schulte, www.ict.kth.se/~cschulte/
>
>
>
> From: users-bounces at gecode.org [mailto:users-bounces at gecode.org] On Behalf
> Of Mailing List Email
> Sent: Wednesday, June 19, 2013 7:49 PM
> To: Amina Kemmar
> Cc: users at gecode.org
> Subject: Re: [gecode-users] Reducing a view domain during propagation
>
>
>
> Sorry, that's bounds consistency.
>
> On 19 Jun 2013 19:23, "Mailing List Email" <mailinglistx at gmail.com> wrote:
>
> Try x1.le(max(s)), x1.ge(min(s)) for domain consistency.
>
> On 19 Jun 2013 19:17, "Amina Kemmar" <kemmar.amina at gmail.com> wrote:
>
> Hi,
>
> In my propagate function that  I implemented, I want to reduce the domain of
> an IntView x1 to a fix set of values given by the strucure set<int> s, how
> can I do this?
>
> Thank you for your help.
> Regards.
>
>
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>
>
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-- 
Dr. Martin Mann, Postdoc
Bioinformatics - Inst. of Computer Science
Albert-Ludwigs-University Freiburg
Tel: ++49-761-203-8254
Fax: ++49-761-203-7462
http://www.bioinf.uni-freiburg.de/~mmann/

-------------- next part --------------
/*
 *  Main authors:
 *     Martin Mann http://www.bioinf.uni-freiburg.de/~mmann/
 *
 *  Contributing authors:
 *     Sebastian Will http://www.bioinf.uni-freiburg.de/~will/
 *
 *  Copyright:
 *     Martin Mann, 2007
 *
 *  This file is part of the CPSP-tools package:
 *     http://www.bioinf.uni-freiburg.de/sw/cpsp/
 *
 *  See the file "LICENSE" for information on usage and
 *  redistribution of this file, and for a
 *     DISCLAIMER OF ALL WARRANTIES.
 *
 */

#include "GC_StlSetRangeIterator.h"
  	
  	GC_StlSetRangeIterator::GC_StlSetRangeIterator() :
  		data(NULL), noFurtherRange(true)
  	{
  		getNextRange();
  	}
  		
	GC_StlSetRangeIterator::GC_StlSetRangeIterator(const std::set<int>* data_) :
		data(data_), noFurtherRange(false)
	{
		if (data != NULL) 
			actElem = data->begin();
		getNextRange();
	}
	
	GC_StlSetRangeIterator::~GC_StlSetRangeIterator()
	{
	}
	
	void
	GC_StlSetRangeIterator::getNextRange() {
		if (data==NULL || actElem == data->end()) {
			noFurtherRange = true;
			return;
		}
			// find next range
		nextMin = *actElem;
		nextMax = nextMin;
			// build up new upper bound until end of set reached or gap in 
			// sequence
		while ( (++actElem != data->end()) && (*actElem == (nextMax+1))) {
			nextMax++;
		}
	}
-------------- next part --------------
/*
 *  Main authors:
 *     Martin Mann http://www.bioinf.uni-freiburg.de/~mmann/
 *
 *  Contributing authors:
 *     Sebastian Will http://www.bioinf.uni-freiburg.de/~will/
 *
 *  Copyright:
 *     Martin Mann, 2007
 *
 *  This file is part of the CPSP-tools package:
 *     http://www.bioinf.uni-freiburg.de/sw/cpsp/
 *
 *  See the file "LICENSE" for information on usage and
 *  redistribution of this file, and for a
 *     DISCLAIMER OF ALL WARRANTIES.
 *
 */

#ifndef GC_STLSETRANGEITERATOR_HH_
#define GC_STLSETRANGEITERATOR_HH_


#include <set>
#include <iostream>
  	
  		/**
  		 * Provides a constant Gecode RangeIterator of a std::set<int> that 
  		 * calculates the ranges on demand.
  		 */
	class GC_StlSetRangeIterator
	{
	private:
		const std::set<int>* data;
		std::set<int>::const_iterator actElem;
		
		bool noFurtherRange;
		
		int nextMin, nextMax;
		
			//! searchs for the next range and sets the inner members
		void getNextRange();
	public:
		GC_StlSetRangeIterator();
		GC_StlSetRangeIterator(const std::set<int>* data_);
		virtual ~GC_StlSetRangeIterator();
		
		void init(const std::set<int>* const data_) {
			data = data_;
			noFurtherRange = false;
			if (data != NULL) 
				actElem = data->begin();
			getNextRange();
		}
		
		bool operator()(void) const { return !noFurtherRange; }
		void operator++(void) { getNextRange(); }
		
		int min(void) const { return nextMin; }
		int max(void) const { return nextMax; }
		unsigned int width(void) { return nextMax-nextMin+1; }
		
		
	};
	

#endif /*GC_STLSETRANGEITERATOR_HH_*/