/// <summary>
/// Moves a piece to another place on the board
/// </summary>
/// <param name="oldBoard"> the board before the piece is moved </param>
/// <param name="pieceToMove"> the piece to be moved on the board </param>
/// <param name="squareToMoveTo"> yhe square to move the piece to </param>
public Move(char[] oldBoard, int pieceToMove, int squareToMoveTo)
{
from = pieceToMove;
to = squareToMoveTo;
newBoard = new char[oldBoard.Length];
for (int i = 0; i < newBoard.Length; i++)
{
if (i == squareToMoveTo)
{
//moves piece to new place
newBoard[i] = oldBoard[pieceToMove];
}
else
{
//Just copy it over
newBoard[i] = oldBoard[i];
}
}
//Enpassant check
if (to == BoardManager.Instance.enPassentIndex && char.ToUpper(oldBoard[from]) == 'P')
{
if (from > to && to + 8 < newBoard.Length)
{
//Moving downward
newBoard[to + 8] = '\0';
enpassentIndex = to + 8;
}
else if (to - 8 >= 0)
{
//Moving upward
newBoard[to - 8] = '\0';
enpassentIndex = to - 8;
}
}
//Promotion Check
if ((char.ToUpper(movedPiece) == 'P') && (to > 55 || to < 8))
{
//Promoted
if (TurnManager.Instance.IsPlayerTurn())
{
//Prompt player for which piece they want
}
else
{
//Choose queen, as statistcally it is the best choice
newBoard[to] = (GameManager.Instance.playerTeam == PieceScript.Team.White) ? 'q' : 'Q';
promotionType = PieceScript.Type.Queen;
}
}
//Remove old piece
newBoard[pieceToMove] = '\0';
//Set Self Fitness
self_fitness = FitnessEvaluator.Evaluate(newBoard);
pathFitness = self_fitness;
}
static void Main(string[] args)
{
string targetPhenotype;
int popSize;
long maxGenerations;
long totalGenerationsPassed = 0;
double bestFitness = 0.0;
double mutationRate;
double crossoverRate;
Random random = new Random();
Stopwatch stopwatch = new Stopwatch();
List <Genome> population = new List <Genome>();
List <Tuple <double, Genome> > evaluatedPopulation = new List <Tuple <double, Genome> >();
List <Task <Tuple <double, Genome> > > taskList = new List <Task <Tuple <double, Genome> > >();
(popSize,
maxGenerations,
mutationRate,
crossoverRate,
targetPhenotype) = MultiStrandCLISetup();
for (int i = 0; i < popSize; i++)
{
/*
* The initial population has random generators seeded with randomly generated numbers.
* That way the states of generators won't be the same and mutations will be applied in more stochastic manner.
*/
population.Add(new Genome(targetPhenotype.Length, random.Next()));
}
stopwatch.Start();
while (bestFitness != 1 && maxGenerations <= totalGenerationsPassed)
{
foreach (Genome genome in population)
{
taskList.Add(
Task.Run(
() => FitnessEvaluator.EvaluateGenome(targetPhenotype, genome)));
}
for (int i = 0; i < popSize; i++)
{
evaluatedPopulation.Add(taskList[i].Result);
}
evaluatedPopulation = evaluatedPopulation.OrderBy(
genomeFitnessPair => genomeFitnessPair.Item1).ToList();
//Clear lists
population.Clear();
taskList.Clear();
//Keep only the 10 best individuals
evaluatedPopulation = evaluatedPopulation.TakeLast(10).ToList();
bestFitness = evaluatedPopulation.Last().Item1;
//Print results every 10th generations or if the optimum fitness is met.
if (totalGenerationsPassed % 10 == 0 || bestFitness == 1.0)
{
Console.WriteLine("Generation: {2} \nBest fitness: {0} \nText: {1} \n\n",
bestFitness,
evaluatedPopulation.First().Item2.Genes,
totalGenerationsPassed);
}
for (int index = 0; index < popSize; index++)
{
if (random.NextDouble() <= crossoverRate)
{
population.Add(
evaluatedPopulation[(index + 1) % evaluatedPopulation.Count].Item2.Cross(
evaluatedPopulation[index % evaluatedPopulation.Count].Item2));
}
else
{
population.Add(evaluatedPopulation[index % evaluatedPopulation.Count].Item2);
}
}
foreach (Genome genome in population)
{
genome.Mutate(mutationRate);
}
population.Add(evaluatedPopulation[0].Item2);
totalGenerationsPassed++;
}
stopwatch.Stop();
Console.WriteLine("Time elapsed: {0:T}", stopwatch.Elapsed);
Console.WriteLine("Over {0} generations.", totalGenerationsPassed);
}
/// <summary>
/// Solves the specified minimum temperature.
/// </summary>
/// <param name="minimumTemperature">The minimum temperature.</param>
/// <param name="maximumTemperature">The maximum temperature.</param>
/// <param name="iterationCount">The iteration count.</param>
/// <param name="fitnessEvaluator">The fitness evaluator.</param>
public void Solve(double minimumTemperature, double maximumTemperature, int iterationCount, FitnessEvaluator fitnessEvaluator)
{
double bestFitness = double.PositiveInfinity;
var bestValues = new double[this.Variables.Length];
//providing initial value for fitness
double Fitness = fitnessEvaluator();
double temperatureIncrement = (maximumTemperature - minimumTemperature) / iterationCount;
for (int i = 0; i <= iterationCount; i++)
{
this.randomizeValues();
//in addition to evaluating fitness, the FitnessEvaluator delegate can also update interface
double currentFitness = fitnessEvaluator();
//updating the best set of variable values
if (currentFitness < bestFitness)
{
for (int j = 0; j < bestValues.Length; j++)
{
bestValues[j] = this.Variables[j].Value;
}
bestFitness = currentFitness;
this.OnBestFitnessUpdated(new UIEventArgs(bestFitness));
}
//annealing core
if (currentFitness < Fitness)
{
Fitness = currentFitness;
this.OnFitnessUpdated(new UIEventArgs(Fitness));
}
else // fitness - currentfitness < 0
{
double temperature = minimumTemperature + (iterationCount - i) * temperatureIncrement;
double power = (Fitness - currentFitness) / temperature;
double p = Math.Exp(power);
double random = this._randomizer.NextDouble();
if (p > random)
{
Fitness = currentFitness;
this.OnFitnessUpdated(new UIEventArgs(Fitness));
}
else //revesring the changes in variable values
{
this.Variables[this._selectedVariableIndex].Value = this._selectedVariablePreviousValue;
}
}
}
//updating the variables with the best set of variables
for (int i = 0; i < this.Variables.Length; i++)
{
this.Variables[i].Value = bestValues[i];
}
}
/// <summary>
/// Creates a population and let it evolve until termination condition is reached.
/// </summary>
/// <param name="terminationCondition">Evolution termination condition evaluated on each new epoch</param>
/// <returns>The best solution found across the evolution</returns>
public ISolution EvolveUntil(TerminationCondition terminationCondition)
{
var rnd = RandomProvider.GetThreadRandom();
var shiftMatrix = MatrixBuilder.Build(this.problem);
var enumerator = new IncreasingRowsRandomColumns(this.problem.Days, this.problem.Slots);
var constraints = ConstraintsBuilder.Build(this.problem);
var chromoProcessor = new ChromosomeProcessor(shiftMatrix, enumerator, constraints);
var evaluator = new FitnessEvaluator(problem);
var fitnessFunction = new Fitness.FitnessFunction(chromoProcessor, evaluator, shiftMatrix);
var chromosomeLength = shiftMatrix.GetNumberOfUnforcedSlots();
const double crossoverProbability = 0.90;
const double mutationProbability = 0.05;
const int elitismPercentage = 5;
epochs = 1;
epochsWithoutFitnessImprovement = 0;
overallBestFitness = -1;
log.Debug("Starting population.");
var population = new Population();
for (var i = 0; i < populationSize; i++)
{
var c = new Double[chromosomeLength];
for (var k = 0; k < chromosomeLength; k++)
{
c[k] = rnd.NextDouble();
}
var ch = new Chromosome(c);
population.Solutions.Add(ch);
}
//create the genetic operators
var elite = new Elite(elitismPercentage);
var crossover = new Crossover(crossoverProbability, true)
{
CrossoverType = CrossoverType.SinglePoint
};
var mutation = new SwapMutate(mutationProbability);
//create the GA itself
var ga = new GeneticAlgorithm(population, fitnessFunction.Evaluate);
//subscribe to the GAs Generation Complete event
ga.OnGenerationComplete += Ga_OnGenerationComplete;
//add the operators to the ga process pipeline
ga.Operators.Add(elite);
ga.Operators.Add(crossover);
ga.Operators.Add(mutation);
//run the GA
ga.Run((pop, currentGeneration, currentEvaluation) =>
{
return(terminationCondition(currentGeneration, epochsWithoutFitnessImprovement, population.MaximumFitness, population.AverageFitness));
});
population.GetTop(1)[0].Evaluate(fitnessFunction.Evaluate);
return(SolutionBuilder.Build(overallBestFitness, shiftMatrix, epochs * population.PopulationSize, this.problem.Items));
}