public void MetropolisCriterion()
{
var lastError = 10;
var currentError = 20;
var temperature = 0.5d;
var res = HeuristicUtils.MetropolisCriterion(lastError, currentError, temperature);
Assert.AreEqual(Math.Exp((lastError - currentError) / temperature), res);
}
public override T[][] SortMatrix(T[][] matrix)
{
var tagVectors = VectorUtils <T> .InitVectors(matrix);
var temperature = 7f;
var error = 0;
var stagnation = 0;
var rand = new Random();
do
{
TagVector <T> tagVector1, tagVector2;
var previousError = error;
error = ErrorTester.GetError(tagVectors);
do
{
tagVector1 = tagVectors[rand.Next() % tagVectors.Count];
tagVector2 = tagVectors[rand.Next() % tagVectors.Count];
} while (!NeighbourTester.AreNeighbours(tagVector1.Pos, tagVector2.Pos));
VectorUtils <T> .SwapVectorPos(tagVector1, tagVector2);
var newError = ErrorTester.GetError(tagVectors);
if (rand.NextDouble() <= HeuristicUtils.MetropolisCriterion(error, newError, temperature))
{
error = newError;
}
else
{
VectorUtils <T> .SwapVectorPos(tagVector1, tagVector2);
}
stagnation = error == previousError ? stagnation + 1 : 0;
if (stagnation > 600)
{
temperature = 7f;
}
temperature = TemperatureUpdater.UpdateTemperature(temperature, 0.999f);
temperature = MathF.Max(temperature, 0.0f);
} while (error > 0);
return(VectorUtils <T> .ConvertVectorsToMatrix(tagVectors));
}
