public ISelection RouletteWheel()
{
var target = new RouletteWheelSelection();
target.SelectChromosomes(_chromosomesNumber, _generation);
return(target);
}
public void SelectChromosomes_Generation_ChromosomesZeroFitness()
{
var target = new RouletteWheelSelection();
var c1 = Substitute.ForPartsOf <ChromosomeBase>(2);
c1.Fitness = 0;
var c2 = Substitute.ForPartsOf <ChromosomeBase>(2);
c2.Fitness = 0;
var c3 = Substitute.ForPartsOf <ChromosomeBase>(2);
c3.Fitness = 0;
var c4 = Substitute.ForPartsOf <ChromosomeBase>(2);
c4.Fitness = 0;
var generation = new Generation(1, new List <IChromosome>()
{
c1, c2, c3, c4
});
var actual = target.SelectChromosomes(2, generation);
Assert.AreEqual(0, actual.Count);
}
public void SelectChromosomes_InvalidNumber_Exception()
{
var target = new RouletteWheelSelection();
ExceptionAssert.IsThrowing(new ArgumentOutOfRangeException("number", "The number of selected chromosomes should be at least 2."), () => {
target.SelectChromosomes(-1, null);
});
ExceptionAssert.IsThrowing(new ArgumentOutOfRangeException("number", "The number of selected chromosomes should be at least 2."), () => {
target.SelectChromosomes(0, null);
});
ExceptionAssert.IsThrowing(new ArgumentOutOfRangeException("number", "The number of selected chromosomes should be at least 2."), () => {
target.SelectChromosomes(1, null);
});
}
public void SelectChromosomes_NullGeneration_Exception()
{
var target = new RouletteWheelSelection();
ExceptionAssert.IsThrowing(new ArgumentNullException("generation"), () => {
target.SelectChromosomes(2, null);
});
}
public void SelectChromosomes_InvalidNumber_Exception()
{
var target = new RouletteWheelSelection();
Assert.Catch <ArgumentOutOfRangeException>(() =>
{
target.SelectChromosomes(-1, null);
}, "The number of selected chromosomes should be at least 2.");
Assert.Catch <ArgumentOutOfRangeException>(() =>
{
target.SelectChromosomes(0, null);
}, "The number of selected chromosomes should be at least 2.");
Assert.Catch <ArgumentOutOfRangeException>(() =>
{
target.SelectChromosomes(1, null);
}, "The number of selected chromosomes should be at least 2.");
}
public void SelectChromosomes_NullGeneration_Exception()
{
var target = new RouletteWheelSelection();
var actual = Assert.Catch <ArgumentNullException>(() =>
{
target.SelectChromosomes(2, null);
});
Assert.AreEqual("generation", actual.ParamName);
}
public void SelectChromosomes_NullFitness_Exception()
{
var target = new RouletteWheelSelection();
var generation = new Generation(1, new List <IChromosome>
{
new TspChromosome(10),
new TspChromosome(10),
new TspChromosome(10),
new TspChromosome(10),
new TspChromosome(10)
});
var actual = Assert.Catch <SelectionException>(() =>
{
target.SelectChromosomes(2, generation);
});
Assert.AreEqual("RouletteWheelSelection: There are chromosomes with null fitness.", actual.Message);
}
public void SelectChromosomes_Generation_ChromosomesSelected()
{
var target = new RouletteWheelSelection();
var c1 = Substitute.ForPartsOf <ChromosomeBase>(2);
c1.Fitness = 0.1;
var c2 = Substitute.ForPartsOf <ChromosomeBase>(2);
c2.Fitness = 0.5;
var c3 = Substitute.ForPartsOf <ChromosomeBase>(2);
c3.Fitness = 0;
var c4 = Substitute.ForPartsOf <ChromosomeBase>(2);
c4.Fitness = 0.7;
var generation = new Generation(1, new List <IChromosome>()
{
c1, c2, c3, c4
});
// Just one selected chromosome is c1.
FlowAssert.IsAtLeastOneAttemptOk(100, () =>
{
var actual = target.SelectChromosomes(2, generation);
Assert.AreEqual(2, actual.Count);
Assert.AreEqual(1, actual.Count(c => c.Fitness == 0.1));
});
// All selected chromosome is c1.
FlowAssert.IsAtLeastOneAttemptOk(1000, () =>
{
var actual = target.SelectChromosomes(2, generation);
Assert.AreEqual(2, actual.Count);
Assert.IsTrue(actual.All(c => c.Fitness == 0.1));
});
// Just one selected chromosome is c2.
FlowAssert.IsAtLeastOneAttemptOk(100, () =>
{
var actual = target.SelectChromosomes(2, generation);
Assert.AreEqual(2, actual.Count);
Assert.AreEqual(1, actual.Count(c => c.Fitness == 0.5));
});
// All selected chromosome is c2.
FlowAssert.IsAtLeastOneAttemptOk(1000, () =>
{
var actual = target.SelectChromosomes(2, generation);
Assert.AreEqual(2, actual.Count);
Assert.IsTrue(actual.All(c => c.Fitness == 0.5));
});
// None selected chromosome is c3.
FlowAssert.IsAtLeastOneAttemptOk(100, () =>
{
var actual = target.SelectChromosomes(2, generation);
Assert.AreEqual(2, actual.Count);
Assert.AreEqual(0, actual.Count(c => c.Fitness == 0.0));
});
// Just one selected chromosome is c4.
FlowAssert.IsAtLeastOneAttemptOk(100, () =>
{
var actual = target.SelectChromosomes(2, generation);
Assert.AreEqual(2, actual.Count);
Assert.AreEqual(1, actual.Count(c => c.Fitness == 0.7));
});
// All selected chromosome is c4.
FlowAssert.IsAtLeastOneAttemptOk(1000, () =>
{
var actual = target.SelectChromosomes(2, generation);
Assert.AreEqual(2, actual.Count);
Assert.IsTrue(actual.All(c => c.Fitness == 0.7));
});
}