/// <summary>
/// Creates an array of neighboroperations.
/// Each operation has a chance to get in the array
/// given by the provided probability distribution.
/// </summary>
/// <param name="probDist">The chance for each operation to get in the array</param>
/// <param name="nOps">Length of the neighboroperations array</param>
/// <returns>An array of neighboroperations</returns>
public NeighborOperation[] GetOperations(double[] probDist, int nOps)
{
NeighborOperation[] res = new NeighborOperation[nOps];
for (int j = 0; j < nOps; j++)
{
double acc = 0;
double p = StaticRandom.NextDouble();
for (int i = 0; i < probDist.Length; i++)
{
acc += probDist[i];
if (p <= acc)
{
res[j] = ops[i](this);
break;
}
}
}
return(res);
}
public override bool GetNext(double[] probDist, int nOps)
{
// Create an array of operators that we are going to perform to generate neighbors
List <NOp> ops = new List <NOp>(schedule.GetOperations(probDist, nOps));
// Take a random operator
// if it may be performed
// - Apply it if the operator decreases the score
// - Apply the operator with chance decpending on the temperator if the score is increased
while (ops.Count != 0)
{
int i = StaticRandom.Next(0, ops.Count);
NOp op = ops[i];
ops.RemoveAt(i);
if (op.Evaluate())
{
double delta = op.TotalDelta;
if (delta < 0)
{
op.Apply();
return(true);
}
else
{
double p = Prob(delta, c);
double r = StaticRandom.NextDouble();
if (p > r)
{
op.Apply();
return(true);
}
}
}
c *= a; // Update temperature
}
return(false);
}