/// <summary>
/// Will compare two instances of genotypes with one another. The comparison is gene by gene.
/// </summary>
/// <remarks>
/// One consequence of how this method is currently implemented is that if there is a random mutation that is a deletion, it will be 'off by one'. In this case, a couple could have a radically different child.
/// This may or may not be a good thing, but it's certainly something to keep in mind.
/// </remarks>
/// <param name="comparison">The genotype to compare with.</param>
/// <returns>The percentage of similarity.</returns>
public double SimilarTo(Genotype comparison)
{
// get the number of genes that are exactly equal in value.
int count = this.Genes.Where((target, iterator) => iterator < comparison.Genes.Count && comparison.Genes[iterator].Value == target.Value).Count();
// return the number of genes that are equal divided by the total number.
return (double)count / Math.Max(this.Genes.Count, comparison.Genes.Count);
}
/// <summary>
/// Will compare two instances of genotypes with one another. The comparison is gene by gene.
/// </summary>
/// <remarks>
/// One consequence of how this method is currently implemented is that if there is a random mutation that is a deletion, it will be 'off by one'. In this case, a couple could have a radically different child.
/// This may or may not be a good thing, but it's certainly something to keep in mind.
/// </remarks>
/// <param name="comparison">The genotype to compare with.</param>
/// <returns>The percentage of similarity.</returns>
public double SimilarTo(Genotype comparison)
{
// get the number of genes that are exactly equal in value.
int count = this.Genes.Where((target, iterator) => iterator < comparison.Genes.Count && comparison.Genes[iterator].Value == target.Value).Count();
// return the number of genes that are equal divided by the total number.
return((double)count / Math.Max(this.Genes.Count, comparison.Genes.Count));
}
/// <summary>
/// The mother and father produces a child.
/// </summary>
/// <returns>The child produced</returns>
public Genotype GetChild()
{
// TODO Add checks for different genotype lengths.
// TODO difference of lengths too great will produce could produce a null offspring
// TODO There is a random chance of producing a null offspring no matter what
// TODO There is a random chance of producing a really crazy off spring?
// TODO Add possibility of multiple children?
var genotype = new Genotype();
for (int i = 0; i < Couple.Mother.Genes.Count; i++)
{
var mutate = this.ShouldMutate();
// Handle different genotype lengths
if (i < Couple.Father.Genes.Count && (Couple.Father.Genes[i] != Couple.Mother.Genes[i] || mutate))
{
if (mutate)
{
this.Mutate(genotype);
}
else
{
// Randomly take mother or father
genotype.Genes.Add(RandomNumberSource.GetNext(1) == 1
? Couple.Mother.Genes[i]
: Couple.Father.Genes[i]);
}
}
else if (i < Couple.Father.Genes.Count)
{
// mothers genes are longer
genotype.Genes.Add(Couple.Mother.Genes[i]);
}
else
{
// they are equal
genotype.Genes.Add(Couple.Mother.Genes[i]);
}
}
if (Couple.Father.Genes.Count > Couple.Mother.Genes.Count)
{
for (var i = Couple.Father.Genes.Count - Couple.Mother.Genes.Count; i < Couple.Father.Genes.Count; i++)
{
if (this.ShouldMutate())
{
this.Mutate(genotype);
}
else
{
genotype.Genes.Add(Couple.Father.Genes[i]);
}
}
}
return genotype;
}
/// <summary>
/// The mother and father produces a child.
/// </summary>
/// <returns>The child produced</returns>
public Genotype GetChild()
{
// TODO Add checks for different genotype lengths.
// TODO difference of lengths too great will produce could produce a null offspring
// TODO There is a random chance of producing a null offspring no matter what
// TODO There is a random chance of producing a really crazy off spring?
// TODO Add possibility of multiple children?
var genotype = new Genotype();
for (int i = 0; i < Couple.Mother.Genes.Count; i++)
{
var mutate = this.ShouldMutate();
// Handle different genotype lengths
if (i < Couple.Father.Genes.Count && (Couple.Father.Genes[i] != Couple.Mother.Genes[i] || mutate))
{
if (mutate)
{
this.Mutate(genotype);
}
else
{
// Randomly take mother or father
genotype.Genes.Add(RandomNumberSource.GetNext(1) == 1
? Couple.Mother.Genes[i]
: Couple.Father.Genes[i]);
}
}
else if (i < Couple.Father.Genes.Count)
{
// mothers genes are longer
genotype.Genes.Add(Couple.Mother.Genes[i]);
}
else
{
// they are equal
genotype.Genes.Add(Couple.Mother.Genes[i]);
}
}
if (Couple.Father.Genes.Count > Couple.Mother.Genes.Count)
{
for (var i = Couple.Father.Genes.Count - Couple.Mother.Genes.Count; i < Couple.Father.Genes.Count; i++)
{
if (this.ShouldMutate())
{
this.Mutate(genotype);
}
else
{
genotype.Genes.Add(Couple.Father.Genes[i]);
}
}
}
return(genotype);
}
/// <summary>
/// Constructs a random genotype of the requested size.
/// </summary>
/// <param name="size">The length of the genome to construct</param>
/// <returns>The constructed Genotype</returns>
public static Genotype GetRandomGenotype(int size)
{
var genotype = new Genotype();
for (var j = 0; j < size; j++)
{
genotype.Genes.Add(Gene.GetRandomGene());
}
return genotype;
}
/// <summary>
/// Constructs a random genotype of the requested size.
/// </summary>
/// <param name="size">The length of the genome to construct</param>
/// <returns>The constructed Genotype</returns>
public static Genotype GetRandomGenotype(int size)
{
var genotype = new Genotype();
for (var j = 0; j < size; j++)
{
genotype.Genes.Add(Gene.GetRandomGene());
}
return(genotype);
}
/// <summary>
/// The create random population.
/// </summary>
/// <param name="populationSize">
/// The population size.
/// </param>
/// <param name="genotypeSize">
/// The genotype size.
/// </param>
/// <param name="chanceOfMutation">
/// The chance of mutation.
/// </param>
/// <returns>
/// The <see cref="Generation"/>.
/// </returns>
public static Generation CreateRandomPopulation(int populationSize, int genotypeSize, double chanceOfMutation)
{
var genotypes = new List <Genotype>();
for (int i = 0; i < populationSize; i++)
{
genotypes.Add(Genotype.GetRandomGenotype(genotypeSize));
}
return(new Generation(chanceOfMutation, genotypes));
}
/// <summary>
/// Performs a mutation on the given genotype
/// </summary>
/// <param name="genotype">
/// The genotype.
/// </param>
private void Mutate(Genotype genotype)
{
// Delete current gene, add 1 random, or 2 random
int next = RandomNumberSource.GetNext(2);
if (next == 2 || next == 1)
{
this.AddRandomGene(genotype);
}
else if (next == 2)
{
this.AddRandomGene(genotype);
}
}
/// <summary>
/// The add random gene.
/// </summary>
/// <param name="genotype">
/// The genotype.
/// </param>
private void AddRandomGene(Genotype genotype)
{
genotype.Genes.Add(Gene.GetRandomGene());
}
/// <summary>
/// Performs a mutation on the given genotype
/// </summary>
/// <param name="genotype">
/// The genotype.
/// </param>
private void Mutate(Genotype genotype)
{
// Delete current gene, add 1 random, or 2 random
int next = RandomNumberSource.GetNext(2);
if (next == 2 || next == 1)
{
this.AddRandomGene(genotype);
}
else if (next == 2)
{
this.AddRandomGene(genotype);
}
}
/// <summary>
/// The add random gene.
/// </summary>
/// <param name="genotype">
/// The genotype.
/// </param>
private void AddRandomGene(Genotype genotype)
{
genotype.Genes.Add(Gene.GetRandomGene());
}