/// <summary>
/// Performs a discrete crossover operation of any number of given parents.
/// </summary>
/// <exception cref="ArgumentException">Thrown when the vectors of the parents are of different length or when there are less than 2 parents.</exception>
/// <param name="random">A random number generator.</param>
/// <param name="parents">The list of parents for the crossover operation.</param>
/// <returns>The newly created integer vector, resulting from the crossover operation.</returns>
public static IntegerVector Apply(IRandom random, ItemArray <IntegerVector> parents)
{
if (parents.Length < 2)
{
throw new ArgumentException("DiscreteCrossover: There are less than two parents to cross.");
}
int length = parents[0].Length;
for (int i = 0; i < parents.Length; i++)
{
if (parents[i].Length != length)
{
throw new ArgumentException("DiscreteCrossover: The parents' vectors are of different length.", "parents");
}
}
var result = new IntegerVector(length);
for (int i = 0; i < length; i++)
{
result[i] = parents[random.Next(parents.Length)][i];
}
return(result);
}
/// <summary>
/// Perfomrs a heuristic crossover on the two given parents.
/// </summary>
/// <exception cref="ArgumentException">Thrown when two parents are not of the same length.</exception>
/// <param name="random">The random number generator.</param>
/// <param name="betterParent">The first parent for the crossover operation.</param>
/// <param name="worseParent">The second parent for the crossover operation.</param>
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
/// <returns>The newly created integer vector, resulting from the heuristic crossover.</returns>
public static IntegerVector Apply(IRandom random, IntegerVector betterParent, IntegerVector worseParent, IntMatrix bounds)
{
if (betterParent.Length != worseParent.Length)
{
throw new ArgumentException("HeuristicCrossover: the two parents are not of the same length");
}
int length = betterParent.Length;
var result = new IntegerVector(length);
double factor = random.NextDouble();
int min, max, step = 1;
for (int i = 0; i < length; i++)
{
min = bounds[i % bounds.Rows, 0];
max = bounds[i % bounds.Rows, 1];
if (bounds.Columns > 2)
{
step = bounds[i % bounds.Rows, 2];
}
max = FloorFeasible(min, max, step, max - 1);
result[i] = RoundFeasible(min, max, step, betterParent[i] + factor * (betterParent[i] - worseParent[i]));
}
return(result);
}
public static double CalculateSimilarity(IntegerVector left, IntegerVector right)
{
if (left == null || right == null)
{
throw new ArgumentException("Cannot calculate similarity because one or both of the provided solutions is null.");
}
if (left.Length != right.Length)
{
throw new ArgumentException("Cannot calculate similarity because the provided solutions have different lengths.");
}
if (left.Length == 0)
{
throw new ArgumentException("Cannot calculate similarity because solutions are of length 0.");
}
if (ReferenceEquals(left, right))
{
return(1.0);
}
double similarity = 0.0;
for (int i = 0; i < left.Length; i++)
{
if (left[i] == right[i])
{
similarity++;
}
}
return(similarity / left.Length);
}
/// <summary>
/// Performs a local crossover on the two given parent vectors.
/// </summary>
/// <exception cref="ArgumentException">Thrown when two parents are not of the same length.</exception>
/// <param name="random">The random number generator.</param>
/// <param name="parent1">The first parent for the crossover operation.</param>
/// <param name="parent2">The second parent for the crossover operation.</param>
/// <returns>The newly created integer vector, resulting from the local crossover.</returns>
public static IntegerVector Apply(IRandom random, IntegerVector parent1, IntegerVector parent2, IntMatrix bounds)
{
if (parent1.Length != parent2.Length)
{
throw new ArgumentException("RoundedLocalCrossover: the two parents are not of the same length");
}
double factor;
int length = parent1.Length;
var result = new IntegerVector(length);
int min, max, step = 1;
for (int i = 0; i < length; i++)
{
min = bounds[i % bounds.Rows, 0];
max = bounds[i % bounds.Rows, 1];
if (bounds.Columns > 2)
{
step = bounds[i % bounds.Rows, 2];
}
max = FloorFeasible(min, max, step, max - 1);
factor = random.NextDouble();
result[i] = RoundFeasible(min, max, step, (factor * parent1[i]) + ((1 - factor) * parent2[i]));
}
return(result);
}
public static void Manipulate(IRandom random, IntegerVector vector, IntMatrix bounds, int index)
{
if (bounds == null || bounds.Rows == 0 || bounds.Columns < 2)
{
throw new ArgumentException("UniformOnePositionManipulator: Invalid bounds specified", "bounds");
}
int min = bounds[index % bounds.Rows, 0], max = bounds[index % bounds.Rows, 1], step = 1;
if (min == max)
{
vector[index] = min;
}
else
{
if (bounds.Columns > 2)
{
step = bounds[index % bounds.Rows, 2];
}
// max has to be rounded to the lower feasible value
// e.g. min...max / step = 0...100 / 5, max is exclusive so it would be 0..99
// but 99 is not a feasible value, so max needs to be adjusted => min = 0, max = 95
max = FloorFeasible(min, max, step, max - 1);
vector[index] = RoundFeasible(min, max, step, random.Next(min, max));
}
}
/// <summary>
/// Genotype-to-Phenotype mapper (iterative breath-first approach, by using a queue -> FIFO).
/// </summary>
/// <param name="startNode">first node of the tree with arity 1</param>
/// <param name="genotype">integer vector, which should be mapped to a tree</param>
/// <param name="grammar">grammar to determine the allowed child symbols for each node</param>
/// <param name="maxSubtreeCount">maximum allowed subtrees (= number of used genomes)</param>
/// <param name="random">random number generator</param>
private void MapBreathFirstIteratively(ISymbolicExpressionTreeNode startNode,
IntegerVector genotype,
ISymbolicExpressionGrammar grammar,
int maxSubtreeCount, IRandom random) {
Queue<Tuple<ISymbolicExpressionTreeNode, int>> queue
= new Queue<Tuple<ISymbolicExpressionTreeNode, int>>(); // tuples of <node, arity>
int genotypeIndex = 0;
queue.Enqueue(new Tuple<ISymbolicExpressionTreeNode, int>(startNode, 1));
while (queue.Count > 0) {
Tuple<ISymbolicExpressionTreeNode, int> current = queue.Dequeue();
// foreach subtree of the current node, create a new node and enqueue it, if it is no terminal node
for (int i = 0; i < current.Item2; ++i) {
if (genotypeIndex >= maxSubtreeCount) {
// if all genomes were used, only add terminal nodes to the remaining subtrees
current.Item1.AddSubtree(GetRandomTerminalNode(current.Item1, grammar, random));
} else {
var newNode = GetNewChildNode(current.Item1, genotype, grammar, genotypeIndex, random);
int arity = SampleArity(random, newNode, grammar);
current.Item1.AddSubtree(newNode);
genotypeIndex++;
if (arity > 0) {
// new node has subtrees so enqueue the node
queue.Enqueue(new Tuple<ISymbolicExpressionTreeNode, int>(newNode, arity));
}
}
}
}
}
/// <summary>
/// Performs the rounded blend alpha crossover (BLX-a) of two integer vectors.<br/>
/// It creates new offspring by sampling a new value in the range [min_i - d * alpha, max_i + d * alpha) at each position i
/// and rounding the result to the next integer.
/// Here min_i and max_i are the smaller and larger value of the two parents at position i and d is max_i - min_i.
/// </summary>
/// <exception cref="ArgumentException">
/// Thrown when <paramref name="parent1"/> and <paramref name="parent2"/> are of different length or<br/>
/// when <paramref name="alpha"/> is less than 0.
/// </exception>
/// <param name="random">The random number generator.</param>
/// <param name="parent1">The first parent for the crossover operation.</param>
/// <param name="parent2">The second parent for the crossover operation.</param>
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
/// <param name="alpha">The alpha value for the crossover.</param>
/// <returns>The newly created integer vector resulting from the crossover operation.</returns>
public static IntegerVector Apply(IRandom random, IntegerVector parent1, IntegerVector parent2, IntMatrix bounds, DoubleValue alpha) {
if (parent1.Length != parent2.Length) throw new ArgumentException("RoundedBlendAlphaCrossover: The parents' vectors are of different length.", "parent1");
if (alpha.Value < 0) throw new ArgumentException("RoundedBlendAlphaCrossover: Paramter alpha must be greater or equal than 0.", "alpha");
if (bounds == null || bounds.Rows < 1 || bounds.Columns < 2) throw new ArgumentException("RoundedBlendAlphaCrossover: Invalid bounds specified.", "bounds");
int length = parent1.Length;
var result = new IntegerVector(length);
double max = 0, min = 0, d = 0, resMin = 0, resMax = 0;
int minBound, maxBound, step = 1;
for (int i = 0; i < length; i++) {
minBound = bounds[i % bounds.Rows, 0];
maxBound = bounds[i % bounds.Rows, 1];
if (bounds.Columns > 2) step = bounds[i % bounds.Rows, 2];
maxBound = FloorFeasible(minBound, maxBound, step, maxBound - 1);
max = Math.Max(parent1[i], parent2[i]);
min = Math.Min(parent1[i], parent2[i]);
d = Math.Abs(max - min);
resMin = FloorFeasible(minBound, maxBound, step, min - d * alpha.Value);
resMax = CeilingFeasible(minBound, maxBound, step, max + d * alpha.Value);
result[i] = RoundFeasible(minBound, maxBound, step, resMin + random.NextDouble() * Math.Abs(resMax - resMin));
}
return result;
}
public static double CalculateSimilarity(IntegerVector left, IntegerVector right, double scaling = 1.0)
{
if (left == null || right == null)
{
throw new ArgumentException("Cannot calculate similarity because one or both of the provided solutions is null.");
}
if (left.Length != right.Length)
{
throw new ArgumentException("Cannot calculate similarity because the provided solutions have different lengths.");
}
if (left.Length == 0)
{
throw new ArgumentException("Cannot calculate similarity because solutions are of length 0.");
}
if (scaling <= 0)
{
throw new ArgumentException("Cannot choose a 0 or negative scaling value.");
}
if (ReferenceEquals(left, right))
{
return(1.0);
}
var distance = 0.0;
for (int i = 0; i < left.Length; i++)
{
distance += (left[i] - right[i]) * (left[i] - right[i]);
}
return(1.0 / (1.0 + Math.Sqrt(distance) / scaling));
}
/// <summary>
/// Generates a new random integer vector with the given <paramref name="length"/>.
/// </summary>
/// <param name="random">The random number generator.</param>
/// <param name="length">The length of the int vector.</param>
/// <param name="bounds">A matrix containing the inclusive lower and inclusive upper bound in the first and second column and a step size in the third column.
/// Each line represents the bounds for a certain dimension. If fewer lines are given, the lines are cycled.</param>
/// <returns>The newly created integer vector.</returns>
public static IntegerVector Apply(IRandom random, int length, IntMatrix bounds)
{
var result = new IntegerVector(length);
result.Randomize(random, bounds);
return(result);
}
/// <summary>
/// Performs a normally distributed all position manipulation on the given
/// <paramref name="vector"/> and rounds the result to the next feasible value.
/// </summary>
/// <exception cref="InvalidOperationException">Thrown when the sigma vector is null or of length 0.</exception>
/// <param name="sigma">The sigma vector determining the strength of the mutation.</param>
/// <param name="random">A random number generator.</param>
/// <param name="vector">The integer vector to manipulate.</param>#
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
/// <returns>The manipulated integer vector.</returns>
public static void Apply(IRandom random, IntegerVector vector, IntMatrix bounds, DoubleArray sigma)
{
if (sigma == null || sigma.Length == 0)
{
throw new ArgumentException("RoundedNormalAllPositionsManipulator: Vector containing the standard deviations is not defined.", "sigma");
}
if (bounds == null || bounds.Rows == 0 || bounds.Columns < 2)
{
throw new ArgumentException("RoundedNormalAllPositionsManipulator: Invalid bounds specified.", "bounds");
}
var N = new NormalDistributedRandom(random, 0.0, 1.0);
for (int i = 0; i < vector.Length; i++)
{
int min = bounds[i % bounds.Rows, 0], max = bounds[i % bounds.Rows, 1], step = 1;
if (bounds.Columns > 2)
{
step = bounds[i % bounds.Rows, 2];
}
int value = (vector[i] + (int)Math.Round((N.NextDouble() * sigma[i % sigma.Length])) - min) / step;
max = FloorFeasible(min, max, step, max - 1);
vector[i] = RoundFeasible(min, max, step, value);
}
}
/// <summary>
/// Changes randomly a single position in the given integer <paramref name="vector"/>.
/// </summary>
/// <remarks>Calls <see cref="Apply"/>.</remarks>
/// <param name="random">A random number generator.</param>
/// <param name="vector">The integer vector to manipulate.</param>
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
protected override void ManipulateBounded(IRandom random, IntegerVector vector, IntMatrix bounds)
{
if (BoundsParameter.ActualValue == null)
{
throw new InvalidOperationException("UniformOnePositionManipulator: Parameter " + BoundsParameter.ActualName + " could not be found.");
}
Apply(random, vector, bounds);
}
protected sealed override void Manipulate(IRandom random, IntegerVector integerVector)
{
if (BoundsParameter.ActualValue == null)
{
throw new InvalidOperationException("BoundedIntegerVectorManipulator: Parameter " + BoundsParameter.ActualName + " could not be found.");
}
ManipulateBounded(random, integerVector, BoundsParameter.ActualValue);
}
/// <summary>
/// Performs a normally distributed all position manipulation on the given
/// <paramref name="vector"/> and rounds the result to the next feasible value.
/// </summary>
/// <exception cref="InvalidOperationException">Thrown when the sigma vector is null or of length 0.</exception>
/// <param name="sigma">The sigma vector determining the strength of the mutation.</param>
/// <param name="random">A random number generator.</param>
/// <param name="vector">The integer vector to manipulate.</param>#
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
/// <returns>The manipulated integer vector.</returns>
public static void Apply(IRandom random, IntegerVector vector, IntMatrix bounds, DoubleArray sigma) {
if (sigma == null || sigma.Length == 0) throw new ArgumentException("RoundedNormalAllPositionsManipulator: Vector containing the standard deviations is not defined.", "sigma");
if (bounds == null || bounds.Rows == 0 || bounds.Columns < 2) throw new ArgumentException("RoundedNormalAllPositionsManipulator: Invalid bounds specified.", "bounds");
var N = new NormalDistributedRandom(random, 0.0, 1.0);
for (int i = 0; i < vector.Length; i++) {
int min = bounds[i % bounds.Rows, 0], max = bounds[i % bounds.Rows, 1], step = 1;
if (bounds.Columns > 2) step = bounds[i % bounds.Rows, 2];
int value = (vector[i] + (int)Math.Round((N.NextDouble() * sigma[i % sigma.Length])) - min) / step;
max = FloorFeasible(min, max, step, max - 1);
vector[i] = RoundFeasible(min, max, step, value);
}
}
/// <summary>
/// Changes randomly several, but at least one, positions in the given integer <paramref name="vector"/>, according to the given probabilities.
/// </summary>
/// <param name="random">A random number generator.</param>
/// <param name="vector">The integer vector to manipulate.</param>
/// <param name="bounds"> Contains the minimum value (inclusive), maximum value (exclusive), and step size of the sampling range for
/// the vector element to change.</param>
/// <param name="probability">The probability for each dimension to be manipulated..</param>
public static void Apply(IRandom random, IntegerVector vector, IntMatrix bounds, double probability) {
if (bounds == null || bounds.Rows == 0 || bounds.Columns < 2) throw new ArgumentException("UniformSomePositionsManipulator: Invalid bounds specified", "bounds");
bool atLeastOneManipulated = false;
for (int index = 0; index < vector.Length; index++) {
if (random.NextDouble() < probability) {
atLeastOneManipulated = true;
UniformOnePositionManipulator.Manipulate(random, vector, bounds, index);
}
}
if (!atLeastOneManipulated) {
UniformOnePositionManipulator.Manipulate(random, vector, bounds, random.Next(vector.Length));
}
}
public static void Manipulate(IRandom random, IntegerVector vector, IntMatrix bounds, int index) {
if (bounds == null || bounds.Rows == 0 || bounds.Columns < 2) throw new ArgumentException("UniformOnePositionManipulator: Invalid bounds specified", "bounds");
int min = bounds[index % bounds.Rows, 0], max = bounds[index % bounds.Rows, 1], step = 1;
if (min == max) {
vector[index] = min;
} else {
if (bounds.Columns > 2) step = bounds[index % bounds.Rows, 2];
// max has to be rounded to the lower feasible value
// e.g. min...max / step = 0...100 / 5, max is exclusive so it would be 0..99
// but 99 is not a feasible value, so max needs to be adjusted => min = 0, max = 95
max = FloorFeasible(min, max, step, max - 1);
vector[index] = RoundFeasible(min, max, step, random.Next(min, max));
}
}
/// <summary>
/// Performs the rounded blend alpha beta crossover (BLX-a-b) on two parent vectors.
/// </summary>
/// <exception cref="ArgumentException">
/// Thrown when either:<br/>
/// <list type="bullet">
/// <item><description>The length of <paramref name="betterParent"/> and <paramref name="worseParent"/> is not equal.</description></item>
/// <item><description>The parameter <paramref name="alpha"/> is smaller than 0.</description></item>
/// <item><description>The parameter <paramref name="beta"/> is smaller than 0.</description></item>
/// </list>
/// </exception>
/// <param name="random">The random number generator to use.</param>
/// <param name="betterParent">The better of the two parents with regard to their fitness.</param>
/// <param name="worseParent">The worse of the two parents with regard to their fitness.</param>
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
/// <param name="alpha">The parameter alpha.</param>
/// <param name="beta">The parameter beta.</param>
/// <returns>The integer vector that results from the crossover.</returns>
public static IntegerVector Apply(IRandom random, IntegerVector betterParent, IntegerVector worseParent, IntMatrix bounds, DoubleValue alpha, DoubleValue beta)
{
if (betterParent.Length != worseParent.Length)
{
throw new ArgumentException("RoundedBlendAlphaBetaCrossover: The parents' vectors are of different length.", "betterParent");
}
if (alpha.Value < 0)
{
throw new ArgumentException("RoundedBlendAlphaBetaCrossover: Parameter alpha must be greater or equal to 0.", "alpha");
}
if (beta.Value < 0)
{
throw new ArgumentException("RoundedBlendAlphaBetaCrossover: Parameter beta must be greater or equal to 0.", "beta");
}
if (bounds == null || bounds.Rows < 1 || bounds.Columns < 2)
{
throw new ArgumentException("RoundedBlendAlphaBetaCrossover: Invalid bounds specified.", "bounds");
}
int length = betterParent.Length;
double min, max, d;
var result = new IntegerVector(length);
int minBound, maxBound, step = 1;
for (int i = 0; i < length; i++)
{
minBound = bounds[i % bounds.Rows, 0];
maxBound = bounds[i % bounds.Rows, 1];
if (bounds.Columns > 2)
{
step = bounds[i % bounds.Rows, 2];
}
maxBound = FloorFeasible(minBound, maxBound, step, maxBound - 1);
d = Math.Abs(betterParent[i] - worseParent[i]);
if (betterParent[i] <= worseParent[i])
{
min = FloorFeasible(minBound, maxBound, step, betterParent[i] - d * alpha.Value);
max = CeilingFeasible(minBound, maxBound, step, worseParent[i] + d * beta.Value);
}
else
{
min = FloorFeasible(minBound, maxBound, step, worseParent[i] - d * beta.Value);
max = CeilingFeasible(minBound, maxBound, step, betterParent[i] + d * alpha.Value);
}
result[i] = RoundFeasible(minBound, maxBound, step, min + random.NextDouble() * (max - min));
}
return(result);
}
public PWREncoding(int nrOfJobs, int nrOfResources, IRandom random)
: base() {
PermutationWithRepetition = new IntegerVector(nrOfJobs * nrOfResources);
int[] lookUpTable = new int[nrOfJobs];
for (int i = 0; i < PermutationWithRepetition.Length; i++) {
int newValue = random.Next(nrOfJobs);
while (lookUpTable[newValue] >= nrOfResources)
newValue = random.Next(nrOfJobs);
PermutationWithRepetition[i] = newValue;
lookUpTable[newValue]++;
}
}
/// <summary>
/// Performs a single point crossover at a randomly chosen position of the two
/// given parent integer vectors.
/// </summary>
/// <param name="random">A random number generator.</param>
/// <param name="parent1">The first parent for crossover.</param>
/// <param name="parent2">The second parent for crossover.</param>
/// <returns>The newly created integer vector, resulting from the single point crossover.</returns>
public static IntegerVector Apply(IRandom random, IntegerVector parent1, IntegerVector parent2) {
if (parent1.Length != parent2.Length)
throw new ArgumentException("SinglePointCrossover: The parents are of different length.");
int length = parent1.Length;
int[] result = new int[length];
int breakPoint = random.Next(1, length);
for (int i = 0; i < breakPoint; i++)
result[i] = parent1[i];
for (int i = breakPoint; i < length; i++)
result[i] = parent2[i];
return new IntegerVector(result);
}
/// <summary>
/// Maps a genotype (an integer vector) to a phenotype (a symbolic expression tree).
/// Random approach.
/// </summary>
/// <param name="random">random number generator</param>
/// <param name="bounds">only used for PIGEMapper (ignore here)</param>
/// <param name="length">only used for PIGEMapper (ignore here)</param>
/// <param name="grammar">grammar definition</param>
/// <param name="genotype">integer vector, which should be mapped to a tree</param>
/// <returns>phenotype (a symbolic expression tree)</returns>
public override SymbolicExpressionTree Map(IRandom random, IntMatrix bounds, int length,
ISymbolicExpressionGrammar grammar,
IntegerVector genotype) {
SymbolicExpressionTree tree = new SymbolicExpressionTree();
var rootNode = (SymbolicExpressionTreeTopLevelNode)grammar.ProgramRootSymbol.CreateTreeNode();
var startNode = (SymbolicExpressionTreeTopLevelNode)grammar.StartSymbol.CreateTreeNode();
rootNode.AddSubtree(startNode);
tree.Root = rootNode;
MapRandomIteratively(startNode, genotype, grammar,
genotype.Length, random);
return tree;
}
/// <summary>
/// Performs a discrete crossover operation of any number of given parents.
/// </summary>
/// <exception cref="ArgumentException">Thrown when the vectors of the parents are of different length or when there are less than 2 parents.</exception>
/// <param name="random">A random number generator.</param>
/// <param name="parents">The list of parents for the crossover operation.</param>
/// <returns>The newly created integer vector, resulting from the crossover operation.</returns>
public static IntegerVector Apply(IRandom random, ItemArray<IntegerVector> parents) {
if (parents.Length < 2) throw new ArgumentException("DiscreteCrossover: There are less than two parents to cross.");
int length = parents[0].Length;
for (int i = 0; i < parents.Length; i++) {
if (parents[i].Length != length)
throw new ArgumentException("DiscreteCrossover: The parents' vectors are of different length.", "parents");
}
var result = new IntegerVector(length);
for (int i = 0; i < length; i++) {
result[i] = parents[random.Next(parents.Length)][i];
}
return result;
}
/// <summary>
/// Performs the arithmetic crossover on some positions by taking either x = alpha * p1 + (1 - alpha) * p2 or x = p1 depending on the probability for a gene to be crossed.
/// </summary>
/// <param name="random">The random number generator.</param>
/// <param name="parent1">The first parent vector.</param>
/// <param name="parent2">The second parent vector.</param>
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
/// <param name="alpha">The alpha parameter (<see cref="AlphaParameter"/>).</param>
/// <param name="probability">The probability parameter (<see cref="ProbabilityParameter"/>).</param>
/// <returns>The vector resulting from the crossover.</returns>
public static IntegerVector Apply(IRandom random, IntegerVector parent1, IntegerVector parent2, IntMatrix bounds, DoubleValue alpha, DoubleValue probability) {
int length = parent1.Length;
if (length != parent2.Length) throw new ArgumentException("RoundedUniformArithmeticCrossover: The parent vectors are of different length.", "parent1");
if (alpha.Value < 0 || alpha.Value > 1) throw new ArgumentException("RoundedUniformArithmeticCrossover: Parameter alpha must be in the range [0;1]", "alpha");
if (probability.Value < 0 || probability.Value > 1) throw new ArgumentException("RoundedUniformArithmeticCrossover: Parameter probability must be in the range [0;1]", "probability");
var result = new IntegerVector(length);
for (int i = 0; i < length; i++) {
if (random.NextDouble() < probability.Value) {
int min = bounds[i % bounds.Rows, 0], max = bounds[i % bounds.Rows, 1], step = 1;
if (bounds.Columns > 2) step = bounds[i % bounds.Rows, 2];
max = FloorFeasible(min, max, step, max - 1);
double value = alpha.Value * parent1[i] + (1 - alpha.Value) * parent2[i];
result[i] = RoundFeasible(min, max, step, value);
} else result[i] = parent1[i];
}
return result;
}
/// <summary>
/// Perfomrs a heuristic crossover on the two given parents.
/// </summary>
/// <exception cref="ArgumentException">Thrown when two parents are not of the same length.</exception>
/// <param name="random">The random number generator.</param>
/// <param name="betterParent">The first parent for the crossover operation.</param>
/// <param name="worseParent">The second parent for the crossover operation.</param>
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
/// <returns>The newly created integer vector, resulting from the heuristic crossover.</returns>
public static IntegerVector Apply(IRandom random, IntegerVector betterParent, IntegerVector worseParent, IntMatrix bounds) {
if (betterParent.Length != worseParent.Length)
throw new ArgumentException("HeuristicCrossover: the two parents are not of the same length");
int length = betterParent.Length;
var result = new IntegerVector(length);
double factor = random.NextDouble();
int min, max, step = 1;
for (int i = 0; i < length; i++) {
min = bounds[i % bounds.Rows, 0];
max = bounds[i % bounds.Rows, 1];
if (bounds.Columns > 2) step = bounds[i % bounds.Rows, 2];
max = FloorFeasible(min, max, step, max - 1);
result[i] = RoundFeasible(min, max, step, betterParent[i] + factor * (betterParent[i] - worseParent[i]));
}
return result;
}
/// <summary>
/// Performs a local crossover on the two given parent vectors.
/// </summary>
/// <exception cref="ArgumentException">Thrown when two parents are not of the same length.</exception>
/// <param name="random">The random number generator.</param>
/// <param name="parent1">The first parent for the crossover operation.</param>
/// <param name="parent2">The second parent for the crossover operation.</param>
/// <returns>The newly created integer vector, resulting from the local crossover.</returns>
public static IntegerVector Apply(IRandom random, IntegerVector parent1, IntegerVector parent2, IntMatrix bounds) {
if (parent1.Length != parent2.Length)
throw new ArgumentException("RoundedLocalCrossover: the two parents are not of the same length");
double factor;
int length = parent1.Length;
var result = new IntegerVector(length);
int min, max, step = 1;
for (int i = 0; i < length; i++) {
min = bounds[i % bounds.Rows, 0];
max = bounds[i % bounds.Rows, 1];
if (bounds.Columns > 2) step = bounds[i % bounds.Rows, 2];
max = FloorFeasible(min, max, step, max - 1);
factor = random.NextDouble();
result[i] = RoundFeasible(min, max, step, (factor * parent1[i]) + ((1 - factor) * parent2[i]));
}
return result;
}
public static OrienteeringEvaluationResult Apply(IntegerVector solution, DoubleArray scores,
DistanceMatrix distances, double maximumDistance, double pointVisitingCosts, double distancePenaltyFactor) {
double score = solution.Sum(t => scores[t]);
double distance = distances.CalculateTourLength(solution.ToList(), pointVisitingCosts);
double distanceViolation = distance - maximumDistance;
double penalty = 0.0;
penalty += distanceViolation > 0 ? distanceViolation * distancePenaltyFactor : 0;
double quality = score - penalty;
return new OrienteeringEvaluationResult {
Quality = new DoubleValue(quality),
Penalty = new DoubleValue(penalty),
Distance = new DoubleValue(distance)
};
}
/// <summary>
/// Performs the rounded blend alpha crossover (BLX-a) of two integer vectors.<br/>
/// It creates new offspring by sampling a new value in the range [min_i - d * alpha, max_i + d * alpha) at each position i
/// and rounding the result to the next integer.
/// Here min_i and max_i are the smaller and larger value of the two parents at position i and d is max_i - min_i.
/// </summary>
/// <exception cref="ArgumentException">
/// Thrown when <paramref name="parent1"/> and <paramref name="parent2"/> are of different length or<br/>
/// when <paramref name="alpha"/> is less than 0.
/// </exception>
/// <param name="random">The random number generator.</param>
/// <param name="parent1">The first parent for the crossover operation.</param>
/// <param name="parent2">The second parent for the crossover operation.</param>
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
/// <param name="alpha">The alpha value for the crossover.</param>
/// <returns>The newly created integer vector resulting from the crossover operation.</returns>
public static IntegerVector Apply(IRandom random, IntegerVector parent1, IntegerVector parent2, IntMatrix bounds, DoubleValue alpha)
{
if (parent1.Length != parent2.Length)
{
throw new ArgumentException("RoundedBlendAlphaCrossover: The parents' vectors are of different length.", "parent1");
}
if (alpha.Value < 0)
{
throw new ArgumentException("RoundedBlendAlphaCrossover: Paramter alpha must be greater or equal than 0.", "alpha");
}
if (bounds == null || bounds.Rows < 1 || bounds.Columns < 2)
{
throw new ArgumentException("RoundedBlendAlphaCrossover: Invalid bounds specified.", "bounds");
}
int length = parent1.Length;
var result = new IntegerVector(length);
double max = 0, min = 0, d = 0, resMin = 0, resMax = 0;
int minBound, maxBound, step = 1;
for (int i = 0; i < length; i++)
{
minBound = bounds[i % bounds.Rows, 0];
maxBound = bounds[i % bounds.Rows, 1];
if (bounds.Columns > 2)
{
step = bounds[i % bounds.Rows, 2];
}
maxBound = FloorFeasible(minBound, maxBound, step, maxBound - 1);
max = Math.Max(parent1[i], parent2[i]);
min = Math.Min(parent1[i], parent2[i]);
d = Math.Abs(max - min);
resMin = FloorFeasible(minBound, maxBound, step, min - d * alpha.Value);
resMax = CeilingFeasible(minBound, maxBound, step, max + d * alpha.Value);
result[i] = RoundFeasible(minBound, maxBound, step, resMin + random.NextDouble() * Math.Abs(resMax - resMin));
}
return(result);
}
/// <summary>
/// Performs an average crossover of the two given parent integer vectors.
/// The average is rounded and mapped to the nearest valid value (e.g. if step size is > 1)
/// </summary>
/// <param name="random">A random number generator.</param>
/// <param name="parents">The parents for crossover.</param>
/// <param name="bounds">The bounds matrix that contains for each dimension one row with minimum (inclusive), maximum (exclusive), and step size columns.
/// If the number of rows is smaller than the number of dimensions the matrix is cycled.</param>
/// <returns>The newly created integer vector, resulting from the single point crossover.</returns>
public static IntegerVector Apply(IRandom random, ItemArray <IntegerVector> parents, IntMatrix bounds)
{
int length = parents[0].Length, parentsCount = parents.Length;
if (parents.Length < 2)
{
throw new ArgumentException("RoundedAverageCrossover: The number of parents is less than 2.", "parents");
}
if (bounds == null || bounds.Rows < 1 || bounds.Columns < 2)
{
throw new ArgumentException("AverageCrossover: Invalid bounds specified.", "bounds");
}
var result = new IntegerVector(length);
try {
double avg;
for (int i = 0; i < length; i++)
{
avg = 0;
for (int j = 0; j < parentsCount; j++)
{
avg += parents[j][i];
}
avg /= parentsCount;
int min = bounds[i % bounds.Rows, 0], max = bounds[i % bounds.Rows, 1], step = 1;
if (bounds.Columns > 2)
{
step = bounds[i % bounds.Rows, 2];
}
max = FloorFeasible(min, max, step, max - 1);
result[i] = RoundFeasible(min, max, step, avg);
}
} catch (IndexOutOfRangeException) {
throw new ArgumentException("RoundedAverageCrossover: The parents' vectors are of different length.", "parents");
}
return(result);
}
/// <summary>
/// Changes randomly several, but at least one, positions in the given integer <paramref name="vector"/>, according to the given probabilities.
/// </summary>
/// <param name="random">A random number generator.</param>
/// <param name="vector">The integer vector to manipulate.</param>
/// <param name="bounds"> Contains the minimum value (inclusive), maximum value (exclusive), and step size of the sampling range for
/// the vector element to change.</param>
/// <param name="probability">The probability for each dimension to be manipulated..</param>
public static void Apply(IRandom random, IntegerVector vector, IntMatrix bounds, double probability)
{
if (bounds == null || bounds.Rows == 0 || bounds.Columns < 2)
{
throw new ArgumentException("UniformSomePositionsManipulator: Invalid bounds specified", "bounds");
}
bool atLeastOneManipulated = false;
for (int index = 0; index < vector.Length; index++)
{
if (random.NextDouble() < probability)
{
atLeastOneManipulated = true;
UniformOnePositionManipulator.Manipulate(random, vector, bounds, index);
}
}
if (!atLeastOneManipulated)
{
UniformOnePositionManipulator.Manipulate(random, vector, bounds, random.Next(vector.Length));
}
}
/// <summary>
/// Performs the arithmetic crossover on some positions by taking either x = alpha * p1 + (1 - alpha) * p2 or x = p1 depending on the probability for a gene to be crossed.
/// </summary>
/// <param name="random">The random number generator.</param>
/// <param name="parent1">The first parent vector.</param>
/// <param name="parent2">The second parent vector.</param>
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
/// <param name="alpha">The alpha parameter (<see cref="AlphaParameter"/>).</param>
/// <param name="probability">The probability parameter (<see cref="ProbabilityParameter"/>).</param>
/// <returns>The vector resulting from the crossover.</returns>
public static IntegerVector Apply(IRandom random, IntegerVector parent1, IntegerVector parent2, IntMatrix bounds, DoubleValue alpha, DoubleValue probability)
{
int length = parent1.Length;
if (length != parent2.Length)
{
throw new ArgumentException("RoundedUniformArithmeticCrossover: The parent vectors are of different length.", "parent1");
}
if (alpha.Value < 0 || alpha.Value > 1)
{
throw new ArgumentException("RoundedUniformArithmeticCrossover: Parameter alpha must be in the range [0;1]", "alpha");
}
if (probability.Value < 0 || probability.Value > 1)
{
throw new ArgumentException("RoundedUniformArithmeticCrossover: Parameter probability must be in the range [0;1]", "probability");
}
var result = new IntegerVector(length);
for (int i = 0; i < length; i++)
{
if (random.NextDouble() < probability.Value)
{
int min = bounds[i % bounds.Rows, 0], max = bounds[i % bounds.Rows, 1], step = 1;
if (bounds.Columns > 2)
{
step = bounds[i % bounds.Rows, 2];
}
max = FloorFeasible(min, max, step, max - 1);
double value = alpha.Value * parent1[i] + (1 - alpha.Value) * parent2[i];
result[i] = RoundFeasible(min, max, step, value);
}
else
{
result[i] = parent1[i];
}
}
return(result);
}
/// <summary>
/// Performs a single point crossover at a randomly chosen position of the two
/// given parent integer vectors.
/// </summary>
/// <param name="random">A random number generator.</param>
/// <param name="parent1">The first parent for crossover.</param>
/// <param name="parent2">The second parent for crossover.</param>
/// <returns>The newly created integer vector, resulting from the single point crossover.</returns>
public static IntegerVector Apply(IRandom random, IntegerVector parent1, IntegerVector parent2)
{
if (parent1.Length != parent2.Length)
{
throw new ArgumentException("SinglePointCrossover: The parents are of different length.");
}
int length = parent1.Length;
int[] result = new int[length];
int breakPoint = random.Next(1, length);
for (int i = 0; i < breakPoint; i++)
{
result[i] = parent1[i];
}
for (int i = breakPoint; i < length; i++)
{
result[i] = parent2[i];
}
return(new IntegerVector(result));
}
/// <summary>
/// Performs an average crossover of the two given parent integer vectors.
/// The average is rounded and mapped to the nearest valid value (e.g. if step size is > 1)
/// </summary>
/// <param name="random">A random number generator.</param>
/// <param name="parents">The parents for crossover.</param>
/// <param name="bounds">The bounds matrix that contains for each dimension one row with minimum (inclusive), maximum (exclusive), and step size columns.
/// If the number of rows is smaller than the number of dimensions the matrix is cycled.</param>
/// <returns>The newly created integer vector, resulting from the single point crossover.</returns>
public static IntegerVector Apply(IRandom random, ItemArray<IntegerVector> parents, IntMatrix bounds) {
int length = parents[0].Length, parentsCount = parents.Length;
if (parents.Length < 2) throw new ArgumentException("RoundedAverageCrossover: The number of parents is less than 2.", "parents");
if (bounds == null || bounds.Rows < 1 || bounds.Columns < 2) throw new ArgumentException("AverageCrossover: Invalid bounds specified.", "bounds");
var result = new IntegerVector(length);
try {
double avg;
for (int i = 0; i < length; i++) {
avg = 0;
for (int j = 0; j < parentsCount; j++)
avg += parents[j][i];
avg /= parentsCount;
int min = bounds[i % bounds.Rows, 0], max = bounds[i % bounds.Rows, 1], step = 1;
if (bounds.Columns > 2) step = bounds[i % bounds.Rows, 2];
max = FloorFeasible(min, max, step, max - 1);
result[i] = RoundFeasible(min, max, step, avg);
}
} catch (IndexOutOfRangeException) {
throw new ArgumentException("RoundedAverageCrossover: The parents' vectors are of different length.", "parents");
}
return result;
}
protected IntegerVector(IntegerVector original, Cloner cloner) : base(original, cloner)
{
}
/// <summary>
/// Returns a randomly chosen child node for the given <paramref name="parentNode"/>.
/// </summary>
/// <param name="parentNode">parent node to find a child node randomly for</param>
/// <param name="genotype">integer vector, which should be mapped to a tree</param>
/// <param name="grammar">grammar used to define the allowed child symbols</param>
/// <param name="genotypeIndex">index in the integer vector; can be greater than vector length</param>
/// <param name="random">random number generator</param>
/// <returns>randomly chosen child node or null, if no child node exits</returns>
protected ISymbolicExpressionTreeNode GetNewChildNode(ISymbolicExpressionTreeNode parentNode,
IntegerVector genotype,
ISymbolicExpressionGrammar grammar,
int genotypeIndex,
IRandom random) {
// only select specific symbols, which can be interpreted ...
IEnumerable<ISymbol> symbolList = (from s in grammar.GetAllowedChildSymbols(parentNode.Symbol)
where s.InitialFrequency > 0.0
select s).ToList();
int prodRuleCount = symbolList.Count();
// no child node exists for the given parent node
if (prodRuleCount < 1) return null;
// genotypeIndex % genotype.Length, if wrapping is allowed
int prodRuleIndex = genotype[genotypeIndex] % prodRuleCount;
var newNode = symbolList.ElementAt(prodRuleIndex).CreateTreeNode();
if (newNode.HasLocalParameters) newNode.ResetLocalParameters(random);
return newNode;
}
protected abstract void ManipulateBounded(IRandom random, IntegerVector integerVector, IntMatrix bounds);
/// <summary>
/// Performs the rounded blend alpha beta crossover (BLX-a-b) on two parent vectors.
/// </summary>
/// <exception cref="ArgumentException">
/// Thrown when either:<br/>
/// <list type="bullet">
/// <item><description>The length of <paramref name="betterParent"/> and <paramref name="worseParent"/> is not equal.</description></item>
/// <item><description>The parameter <paramref name="alpha"/> is smaller than 0.</description></item>
/// <item><description>The parameter <paramref name="beta"/> is smaller than 0.</description></item>
/// </list>
/// </exception>
/// <param name="random">The random number generator to use.</param>
/// <param name="betterParent">The better of the two parents with regard to their fitness.</param>
/// <param name="worseParent">The worse of the two parents with regard to their fitness.</param>
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
/// <param name="alpha">The parameter alpha.</param>
/// <param name="beta">The parameter beta.</param>
/// <returns>The integer vector that results from the crossover.</returns>
public static IntegerVector Apply(IRandom random, IntegerVector betterParent, IntegerVector worseParent, IntMatrix bounds, DoubleValue alpha, DoubleValue beta) {
if (betterParent.Length != worseParent.Length) throw new ArgumentException("RoundedBlendAlphaBetaCrossover: The parents' vectors are of different length.", "betterParent");
if (alpha.Value < 0) throw new ArgumentException("RoundedBlendAlphaBetaCrossover: Parameter alpha must be greater or equal to 0.", "alpha");
if (beta.Value < 0) throw new ArgumentException("RoundedBlendAlphaBetaCrossover: Parameter beta must be greater or equal to 0.", "beta");
if (bounds == null || bounds.Rows < 1 || bounds.Columns < 2) throw new ArgumentException("RoundedBlendAlphaBetaCrossover: Invalid bounds specified.", "bounds");
int length = betterParent.Length;
double min, max, d;
var result = new IntegerVector(length);
int minBound, maxBound, step = 1;
for (int i = 0; i < length; i++) {
minBound = bounds[i % bounds.Rows, 0];
maxBound = bounds[i % bounds.Rows, 1];
if (bounds.Columns > 2) step = bounds[i % bounds.Rows, 2];
maxBound = FloorFeasible(minBound, maxBound, step, maxBound - 1);
d = Math.Abs(betterParent[i] - worseParent[i]);
if (betterParent[i] <= worseParent[i]) {
min = FloorFeasible(minBound, maxBound, step, betterParent[i] - d * alpha.Value);
max = CeilingFeasible(minBound, maxBound, step, worseParent[i] + d * beta.Value);
} else {
min = FloorFeasible(minBound, maxBound, step, worseParent[i] - d * beta.Value);
max = CeilingFeasible(minBound, maxBound, step, betterParent[i] + d * alpha.Value);
}
result[i] = RoundFeasible(minBound, maxBound, step, min + random.NextDouble() * (max - min));
}
return result;
}
public abstract SymbolicExpressionTree Map(IRandom random, IntMatrix bounds, int length,
ISymbolicExpressionGrammar grammar,
IntegerVector genotype);
/// <summary>
/// Genotype-to-Phenotype mapper (iterative depth-first approach, by using a stack -> LIFO).
/// </summary>
/// <param name="startNode">first node of the tree with arity 1</param>
/// <param name="genotype">integer vector, which should be mapped to a tree</param>
/// <param name="grammar">grammar to determine the allowed child symbols for each node</param>
/// <param name="maxSubtreeCount">maximum allowed subtrees (= number of used genomes)</param>
/// <param name="random">random number generator</param>
private void MapDepthFirstIteratively(ISymbolicExpressionTreeNode startNode,
IntegerVector genotype,
ISymbolicExpressionGrammar grammar,
int maxSubtreeCount, IRandom random) {
Stack<Tuple<ISymbolicExpressionTreeNode, int>> stack
= new Stack<Tuple<ISymbolicExpressionTreeNode, int>>(); // tuples of <node, arity>
int genotypeIndex = 0;
stack.Push(new Tuple<ISymbolicExpressionTreeNode, int>(startNode, 1));
while (stack.Count > 0) {
// get next node from stack and re-push it, if this node still has unhandled subtrees ...
Tuple<ISymbolicExpressionTreeNode, int> current = stack.Pop();
if (current.Item2 > 1) {
stack.Push(new Tuple<ISymbolicExpressionTreeNode, int>(current.Item1, current.Item2 - 1));
}
if (genotypeIndex >= maxSubtreeCount) {
// if all genomes were used, only add terminal nodes to the remaining subtrees
current.Item1.AddSubtree(GetRandomTerminalNode(current.Item1, grammar, random));
} else {
var newNode = GetNewChildNode(current.Item1, genotype, grammar, genotypeIndex, random);
int arity = SampleArity(random, newNode, grammar);
current.Item1.AddSubtree(newNode);
genotypeIndex++;
if (arity > 0) {
// new node has subtrees so push it onto the stack
stack.Push(new Tuple<ISymbolicExpressionTreeNode, int>(newNode, arity));
}
}
}
}
public static PWREncoding CreateTestPWR2() {
PWREncoding result = new PWREncoding();
IntegerVector pwr = new IntegerVector(new int[] { 0, 1, 1, 0, 2, 0, 1, 2, 2 });
result.PermutationWithRepetition = pwr;
return result;
}
protected sealed override void Manipulate(IRandom random, IntegerVector integerVector) {
if (BoundsParameter.ActualValue == null) throw new InvalidOperationException("BoundedIntegerVectorManipulator: Parameter " + BoundsParameter.ActualName + " could not be found.");
ManipulateBounded(random, integerVector, BoundsParameter.ActualValue);
}
/// <summary>
/// Maps a genotype (an integer vector) to a phenotype (a symbolic expression tree).
/// PIGE approach.
/// </summary>
/// <param name="random">random number generator</param>
/// <param name="bounds">integer number range for genomes (codons) of the nont vector</param>
/// <param name="length">length of the nont vector to create</param>
/// <param name="grammar">grammar definition</param>
/// <param name="genotype">integer vector, which should be mapped to a tree</param>
/// <returns>phenotype (a symbolic expression tree)</returns>
public override ISymbolicExpressionTree Map(IRandom random, IntMatrix bounds, int length,
ISymbolicExpressionGrammar grammar,
IntegerVector genotype) {
SymbolicExpressionTree tree = new SymbolicExpressionTree();
var rootNode = (SymbolicExpressionTreeTopLevelNode)grammar.ProgramRootSymbol.CreateTreeNode();
var startNode = (SymbolicExpressionTreeTopLevelNode)grammar.StartSymbol.CreateTreeNode();
rootNode.AddSubtree(startNode);
tree.Root = rootNode;
// Map can be called simultaniously on multiple threads
lock (nontVectorLocker) {
if (NontVector == null) {
NontVector = GetNontVector(random, bounds, length);
}
}
MapPIGEIteratively(startNode, genotype, grammar,
genotype.Length, random);
return tree;
}
/// <summary>
/// Retrieves the bounds and forwards the call to the static Apply method.
/// </summary>
/// <param name="random">The random number generator.</param>
/// <param name="vector">The vector of integer values that is manipulated.</param>
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
protected override void ManipulateBounded(IRandom random, IntegerVector vector, IntMatrix bounds) {
Apply(random, vector, bounds, SigmaParameter.Value);
}
protected abstract void ManipulateBounded(IRandom random, IntegerVector integerVector, IntMatrix bounds);
protected abstract void Manipulate(IRandom random, IntegerVector integerVector);
private static IntegerVector GetNontVector(IRandom random, IntMatrix bounds, int length) {
IntegerVector v = new IntegerVector(length);
v.Randomize(random, bounds);
return v;
}
/// <summary>
/// Genotype-to-Phenotype mapper (iterative 𝜋GE approach, using a list of not expanded nonTerminals).
/// </summary>
/// <param name="startNode">first node of the tree with arity 1</param>
/// <param name="genotype">integer vector, which should be mapped to a tree</param>
/// <param name="grammar">grammar to determine the allowed child symbols for each node</param>
/// <param name="maxSubtreeCount">maximum allowed subtrees (= number of used genomes)</param>
/// <param name="random">random number generator</param>
private void MapPIGEIteratively(ISymbolicExpressionTreeNode startNode,
IntegerVector genotype,
ISymbolicExpressionGrammar grammar,
int maxSubtreeCount, IRandom random) {
List<ISymbolicExpressionTreeNode> nonTerminals = new List<ISymbolicExpressionTreeNode>();
int genotypeIndex = 0;
nonTerminals.Add(startNode);
while (nonTerminals.Count > 0) {
if (genotypeIndex >= maxSubtreeCount) {
// if all genomes were used, only add terminal nodes to the remaining subtrees
ISymbolicExpressionTreeNode current = nonTerminals[0];
nonTerminals.RemoveAt(0);
current.AddSubtree(GetRandomTerminalNode(current, grammar, random));
} else {
// Order: NT = nont % Num. NT
int nt = NontVector[genotypeIndex] % nonTerminals.Count;
ISymbolicExpressionTreeNode current = nonTerminals[nt];
nonTerminals.RemoveAt(nt);
// Content: Rule = rule % Num. Rules
ISymbolicExpressionTreeNode newNode = GetNewChildNode(current, genotype, grammar, genotypeIndex, random);
int arity = SampleArity(random, newNode, grammar);
current.AddSubtree(newNode);
genotypeIndex++;
// new node has subtrees, so add "arity" number of copies of this node to the nonTerminals list
for (int i = 0; i < arity; ++i) {
nonTerminals.Add(newNode);
}
}
}
}
/// <summary>
/// Changes randomly several, but at least one, positions in the given integer <paramref name="vector"/>.
/// </summary>
/// <remarks>Calls <see cref="Apply"/>.</remarks>
/// <param name="random">A random number generator.</param>
/// <param name="vector">The integer vector to manipulate.</param>
protected override void ManipulateBounded(IRandom random, IntegerVector vector, IntMatrix bounds) {
Apply(random, vector, bounds, ProbabilityParameter.ActualValue.Value);
}
/// <summary>
/// Retrieves the bounds and forwards the call to the static Apply method.
/// </summary>
/// <param name="random">The random number generator.</param>
/// <param name="vector">The vector of integer values that is manipulated.</param>
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
protected override void ManipulateBounded(IRandom random, IntegerVector vector, IntMatrix bounds)
{
Apply(random, vector, bounds, SigmaParameter.Value);
}
/// <summary>
/// Changes randomly a single position in the given integer <paramref name="vector"/>.
/// </summary>
/// <param name="random">A random number generator.</param>
/// <param name="vector">The integer vector to manipulate.</param>
/// <param name="min">The minimum value of the sampling range for
/// the vector element to change (inclusive).</param>
/// <param name="max">The maximum value of the sampling range for
/// the vector element to change (exclusive).</param>
/// <param name="bounds">The bounds and step size for each dimension (will be cycled in case there are less rows than elements in the parent vectors).</param>
public static void Apply(IRandom random, IntegerVector vector, IntMatrix bounds)
{
Manipulate(random, vector, bounds, random.Next(vector.Length));
}
/// <summary>
/// Changes randomly several, but at least one, positions in the given integer <paramref name="vector"/>.
/// </summary>
/// <remarks>Calls <see cref="Apply"/>.</remarks>
/// <param name="random">A random number generator.</param>
/// <param name="vector">The integer vector to manipulate.</param>
protected override void ManipulateBounded(IRandom random, IntegerVector vector, IntMatrix bounds)
{
Apply(random, vector, bounds, ProbabilityParameter.ActualValue.Value);
}
public PRVEncoding(IntegerVector iv, IntValue nrOfRules)
: base() {
this.nrOfRules = (IntValue)nrOfRules.Clone();
this.PriorityRulesVector = (IntegerVector)iv.Clone();
}
/// <summary>
/// Genotype-to-Phenotype mapper (iterative random approach, where the next non-terminal
/// symbol to expand is randomly determined).
/// </summary>
/// <param name="startNode">first node of the tree with arity 1</param>
/// <param name="genotype">integer vector, which should be mapped to a tree</param>
/// <param name="grammar">grammar to determine the allowed child symbols for each node</param>
/// <param name="maxSubtreeCount">maximum allowed subtrees (= number of used genomes)</param>
/// <param name="random">random number generator</param>
private void MapRandomIteratively(ISymbolicExpressionTreeNode startNode,
IntegerVector genotype,
ISymbolicExpressionGrammar grammar,
int maxSubtreeCount, IRandom random) {
List<ISymbolicExpressionTreeNode> nonTerminals = new List<ISymbolicExpressionTreeNode>();
int genotypeIndex = 0;
nonTerminals.Add(startNode);
while (nonTerminals.Count > 0) {
if (genotypeIndex >= maxSubtreeCount) {
// if all genomes were used, only add terminal nodes to the remaining subtrees
ISymbolicExpressionTreeNode current = nonTerminals[0];
nonTerminals.RemoveAt(0);
current.AddSubtree(GetRandomTerminalNode(current, grammar, random));
} else {
// similar to PIGEMapper, but here the current node is determined randomly ...
ISymbolicExpressionTreeNode current = nonTerminals.SampleRandom(random);
nonTerminals.Remove(current);
ISymbolicExpressionTreeNode newNode = GetNewChildNode(current, genotype, grammar, genotypeIndex, random);
int arity = SampleArity(random, newNode, grammar);
current.AddSubtree(newNode);
genotypeIndex++;
// new node has subtrees, so add "arity" number of copies of this node to the nonTerminals list
for (int i = 0; i < arity; ++i) {
nonTerminals.Add(newNode);
}
}
}
}
protected IntegerVector(IntegerVector original, Cloner cloner) : base(original, cloner) { }
protected abstract void Manipulate(IRandom random, IntegerVector integerVector);