// -------------- RNG methods ------
private Numeric <T, C> ___nextFromMinusOneToPlusOne()
{
// Берем число в [0; 1)
// и вычитаем число из [0; 1)
// Получаем число от -1 до +1 :)
return(Numeric <T, C> .Calculator.dif(generator.Next_SingleInterval(), generator.Next_SingleInterval()));
}
/// <summary>
/// Performs a high-quality random shuffling of the list.
/// Uses a user-provided random number generator, which
/// </summary>
/// <typeparam name="T">The type of elements in the list.</typeparam>
/// <typeparam name="N">The type of numbers generated by the random numbers generator.</typeparam>
/// <param name="list">The calling list object.</param>
/// <param name="generator">A floating-point random number generator for the <typeparamref name="N"/> type.</param>
/// <param name="numericComparer">An optional numeric comparer for <typeparamref name="N"/> type. If <c>null</c>, a standard comparer will be used (if exists, otherwise, an exception will be thrown).</param>
public static void Shuffle <T, N>(this IList <T> list, IRandomFloatingPoint <N> generator, IComparer <N> numericComparer = null)
{
Contract.Requires <ArgumentNullException>(list != null, "list");
Contract.Requires <ArgumentNullException>(generator != null, "generator");
if (numericComparer == null)
{
numericComparer = Comparer <N> .Default;
}
// Генерируем массив пар со случайными ключами,
// сортируем их по ключу (а значения оказываются случайно перемешанными).
List <KeyValuePair <N, T> > pairList = new List <KeyValuePair <N, T> >(list.Count);
foreach (T element in list)
{
pairList.Add(new KeyValuePair <N, T>(generator.Next_SingleInterval(), element));
}
IComparer <KeyValuePair <N, T> > pairComparer = numericComparer.createKVPComparerOnKey <N, T>();
pairList.Sort(pairComparer);
// Восстанавливаем.
for (int i = 0; i < pairList.Count; i++)
{
list[i] = pairList[i].Value;
}
}
/// <summary>
/// Constructs a Fibonacci lagged pseudo-random number generator using the lag values and
/// another generator for the first sequence members.
///
/// Examples of recommended lag values:
///
/// a) 17; 5
/// b) 55; 24
/// c) 97; 33.
///
/// It is not recommended to provide random lag values as it will affect
/// the quality of the generator randomization.
/// </summary>
/// <param name="firstGenerator">The IRandom(T) implementer object to receive the first values of the pseudo-random sequence.</param>
/// <param name="a">The first lag of the fibonacci generator. Optional. By default, equals 97.</param>
/// <param name="b">The second lag of the fibonacci generator. Optional. By default, equals 33.</param>
public RandomLaggedFibonacci(IRandomFloatingPoint <double> firstGenerator, int a = 97, int b = 33)
{
this.a = a;
this.b = b;
this.max = Math.Max(a, b);
for (int i = 0; i < max; i++)
{
list.AddLast(firstGenerator.Next_SingleInterval());
}
xkmaNode = list.First;
xkmbNode = list.First;
for (int i = 0; i < max - a; i++)
{
xkmaNode = xkmaNode.Next;
}
for (int i = 0; i < max - b; i++)
{
xkmbNode = xkmbNode.Next;
}
return;
}
