private static void AssertExpectedDistribution(int numberOfSides, DiscreteValueProbabilityDistribution actualDistribution)
{
var rng = MockRepository.GenerateStub <IRandomNumberGenerator>();
var die = new NumericalDie(numberOfSides, rng);
DiscreteValueProbabilityDistribution expectedDistribution = die.ProbabilityDistribution;
AssertEquals(expectedDistribution, actualDistribution);
}
public void Constructor_ExpectedValues(int numberOfSides)
{
// Setup
var rng = MockRepository.GenerateStub <IRandomNumberGenerator>();
// Call
var die = new NumericalDie(numberOfSides, rng);
// Assert
Assert.IsInstanceOf <AbstractDie>(die);
Assert.AreEqual(numberOfSides, die.NumberOfSides);
}
public void ProbabilityDistribution_ForSomeNumberOfSides_DefinesUniformProbabilityDistribution(int numberOfSides)
{
// Setup
var rng = MockRepository.GenerateStub <IRandomNumberGenerator>();
var die = new NumericalDie(numberOfSides, rng);
// Call
DiscreteValueProbabilityDistribution distribution = die.ProbabilityDistribution;
// Assert
double uniformProbability = 1.0 / numberOfSides;
foreach (ValueProbabilityPair pair in distribution.Specification)
{
Assert.AreEqual(uniformProbability, pair.Probability);
}
CollectionAssert.AreEquivalent(Enumerable.Range(1, numberOfSides), distribution.Specification.Select(p => p.Value));
}
public void Roll_ReturnRandomlyGeneratedValuesAccordingToProbabilityDistribution()
{
// Setup
const double uniformProbability = 1.0 / 6.0;
var rngValueAndExpectedResults = new[]
{
Tuple.Create(0.0, 1),
Tuple.Create(0.45 * uniformProbability, 1),
Tuple.Create(uniformProbability, 1),
Tuple.Create(uniformProbability + 1e-6, 2),
Tuple.Create(1.34 * uniformProbability, 2),
Tuple.Create(2 * uniformProbability, 2),
Tuple.Create((2 * uniformProbability) + 1e-6, 3),
Tuple.Create(2.89 * uniformProbability, 3),
Tuple.Create(3 * uniformProbability, 3),
Tuple.Create((3 * uniformProbability) + 1e-6, 4),
Tuple.Create(3.75 * uniformProbability, 4),
Tuple.Create(4 * uniformProbability, 4),
Tuple.Create((4 * uniformProbability) + 1e-6, 5),
Tuple.Create(4.28 * uniformProbability, 5),
Tuple.Create(5 * uniformProbability, 5),
Tuple.Create((5 * uniformProbability) + 1e-6, 6),
Tuple.Create(5.83 * uniformProbability, 6),
Tuple.Create(6 * uniformProbability, 6),
};
var rng = new TestingRandomNumberGenerator();
rng.AddFactorValues(rngValueAndExpectedResults.Select(t => t.Item1));
var die = new NumericalDie(6, rng);
foreach (Tuple <double, int> pair in rngValueAndExpectedResults)
{
// Call
int dieResult = die.Roll();
// Assert
Assert.AreEqual(pair.Item2, dieResult, $"Asserting for probability value {pair.Item1}.");
}
}
public void ProbabilityDistribution_AddingValueTo1D6_ReturnExpectedDistribution(int modifierValue)
{
// Setup
var rng = MockRepository.GenerateStub <IRandomNumberGenerator>();
var die = new NumericalDie(6, rng);
var modifier = new DiceModifier(die, modifierValue, rng);
// Call
DiscreteValueProbabilityDistribution distribution = modifier.ProbabilityDistribution;
// Assert
ReadOnlyCollection <ValueProbabilityPair> specification = die.ProbabilityDistribution.Specification;
Assert.AreEqual(specification.Count, distribution.Specification.Count);
for (int i = 0; i < specification.Count; i++)
{
ValueProbabilityPair referencePair = specification[i];
ValueProbabilityPair actualPair = distribution.Specification[i];
Assert.AreEqual(referencePair.Probability, actualPair.Probability);
Assert.AreEqual(referencePair.Value + modifierValue, actualPair.Value);
}
}
