public static void Run(Graph graph, Action refresh, Size size)
{
if (!IsRun)
{
IsRun = true;
ThreadPool.QueueUserWorkItem(state =>
{
var avgEdgeLength = graph.SelectMany(x => x.Edges.Select(e => e.GetLength())).Average();
Func <double> GetSolutionCost = () => CalcSolutionCost(graph, avgEdgeLength);
var rand = new Random(DateTime.Now.Millisecond);
Temperature = INITIAL_TEMPERATURE;
double solutionCost = GetSolutionCost();
for (int i = 0; i < COOLING_STEP; i++)
{
Temperature *= COOLING_FRACTION;
var startValue = solutionCost;
for (int j = 0; j < STEPS_PER_TEMP; j++)
{
var vertexIndex = rand.Next(0, graph.Count);
var vertex = graph[vertexIndex];
var moveDirection = (Direction)rand.Next(0, 7);
var moveDistance = (float)rand.NextDouble() * avgEdgeLength;
var position = vertex.Position;
Move(vertex, moveDirection, moveDistance, size);
refresh();
var flip = rand.NextDouble() * 1.1;
var currentSolutionCost = GetSolutionCost();
var delta = solutionCost - currentSolutionCost;
var exponent = (-delta / solutionCost) / (K * Temperature);
var merit = Math.Pow(Math.E, exponent);
if (delta < 0) //Принять удачный вариант
{
solutionCost = currentSolutionCost;
refresh();
}
else
{
if (merit > flip) //Принять неудачный вариант
{
solutionCost = currentSolutionCost;
refresh();
}
else //Отклонить
{
vertex.Position = position;
}
}
}
if (solutionCost - startValue < 0)
{
Temperature = Temperature / COOLING_FRACTION;
}
}
IsRun = false;
});
}
}
private static double CalcSolutionCost(Graph graph, float edgeLength)
{
var c = graph.SelectMany(x => x.Edges.Select(e => e.GetLength())).Where(x => Math.Abs(x / edgeLength) > 0.9 && Math.Abs(x / edgeLength) < 1.1).Count() / 2;
return((((double)c * 2) / graph.SelectMany(x => x.Edges).Count()) * 100.0);
}
