C++ Chromosome::swapNodesOpt方法代码示例

//maxtime in seconds
ExperimentResult iterativeLocalSearch(int size, int perturbationSize, Chromosome::GenerationType genType, int maxIterations = 50, time_t maxTime = -1) {
//	ofstream ILSsolution;
//	ILSsolution.open("ILSsolution.txt");
	double maxDeviation = 1.2;

	Chromosome candidate = Chromosome(size, genType);
	candidate.swapNodesOpt();

	Chromosome bestSolution(candidate);

	time_t endTime = time(0) + maxTime;
	if (maxTime < 0){
		endTime = numeric_limits<long>::max();
	}

	if (maxIterations < 0){
		maxIterations = numeric_limits<int>::max();
	}

	int i = 0;
	while (maxIterations > i && time(0) < endTime) {
		candidate.mutate(perturbationSize);
		candidate.swapNodesOpt();

		//if the score is very bad -> use the old optimal solution to perturbate from
		if (candidate._score < bestSolution._score){
			bestSolution = candidate;
		}
		else if (candidate._score > bestSolution._score * maxDeviation){
			candidate = bestSolution;
		}
//		ILSsolution << candidate << endl;

		i++;
	}

//	ILSsolution.close();
	ExperimentResult result;
	result.bestScore = bestSolution._score;
	result.iterations = i;
	return result;
}

ExperimentResult dynamicPathRelinking(int ESSize, int globalIter, int localIter, int dth, Chromosome::GenerationType genType, double truncate = 1, time_t maxTime = MAX_TIME) {
	// - construct elite set (ES) with size b solutions
	vector<Chromosome> es;
	for (int i = 0; i < ESSize; ++i) {
		Chromosome chrom(Chromosome::_nodeList.size(), genType);
		chrom.swapNodesOpt();
		es.push_back(chrom);
	}
	sort(es.begin(), es.end(), [](const Chromosome & a, const Chromosome & b) {return a._score < b._score; });

	// - sort ES by score

	time_t endTime = time(0) + maxTime;
	if (maxTime < 0){
		endTime = numeric_limits<long>::max();
	}

	int gi;
	for (gi = 0; gi < globalIter && time(0) < endTime; ++gi) { // or just set time limit
//		cout << "iteration: " << gi << endl;
		for (int li = 0; li < localIter; ++li) {
//			cout << "iteration: " << gi << " / " << li << endl;
//			cout << "gcrCalls: " << Chromosome::gcrCalls << endl;
			// - construct solution
			Chromosome x(Chromosome::_nodeList.size(), genType);

			// - local search
			x.swapNodesOpt();
			// - random select xj from ES
			int j = rand() % ESSize;

			// - get best solution from PR
			// - local search and save to y
//			Chromosome y = Chromosome::PathRelink(x, es[j]);
			Chromosome y = Chromosome::GACrossOver(x, es[j]);
			y.swapNodesOpt();

			if (y._score > x._score) { //uncomment for GACrossover
				y = x;
			}

			if (y._score < es[0]._score) { // - if the solution is better than the best in ES replace it
				es[0] = y;
			}
			else if (y._score < es[ESSize - 1]._score) { // - elseif solution is better than the worst in ES and hamming distance is smaller than dth
				bool addToEs = true;
				vector<int> distances(ESSize);
				for (int i = 0; i < ESSize; ++i) {
					distances[i] = Chromosome::distance(y, es[i]);
					if (distances[i] <= dth) {
						addToEs = false;
						break;
					}
				}
				if (addToEs) {
//					cout << "better ES member recombined" << endl;
					// find the closest solution in ES (by hamming distance) to y such that score y._score is better
					int swapId;
					int swapDistance = numeric_limits<int>::max();;
					for (int i = 0; i < ESSize; ++i) {
						if (y._score < es[i]._score) {
							if (distances[i] < swapDistance) {
								swapId = i;
								swapDistance = distances[i];
							}
						}
					}
					// replace them
					es[swapId] = y;
					// sort ES
					sort(es.begin(), es.end(), [](const Chromosome & a, const Chromosome & b) {return a._score < b._score; });
				}
			}
		}

		int map[30][30];
		for (int k = 0; k < ESSize; ++k) {
			for (int i = 0; i < ESSize; ++i) {
				map[k][i] = 0;
			}
		}

		bool newSol = true;
		while (newSol) {
			newSol = false;

			for (int i = 0; i < ESSize; ++i) {
				for (int j = 0; j < ESSize / 2; ++j) {

					// not need to generate those that were generated before
					if (map[i][j] == 1) {
						continue;
					}
					else {
						map[i][j] = 1;
					}

//					cout << "combining " << i << " " << j << endl;

					Chromosome y = Chromosome::GACrossOver(es[i], es[j]);
//.........这里部分代码省略.........