public static void Main(string[] args)
{
Combinatorics obj = new Combinatorics();
int[] array = new int[] { 1, 2, 3, 4, 5};
obj.Permute(array);
obj.Combine(array);
}
public static void Main(string[] args)
{
Combinatorics obj = new Combinatorics();
int[] array = new int[] { 1, 2, 3, 4, 5 };
obj.Permute(array);
obj.Combine(array);
}
/// <summary>
/// Создает ConvexHull из системы линейных уравнений A*x <= b
/// </summary>
/// <param name="A">Матрица A</param>
/// <param name="b">вектор b</param>
/// <returns></returns>
public static ConvexHull CreateFromHPolytope(double[][] A, double[] b)
{
int[] rowsNumbers = A.Select((x, i) => i).ToArray();
int varsCount = A[0].Count();
List <double[]> vertices = new List <double[]>();
foreach (var combination in Combinatorics.Combinations(rowsNumbers, varsCount))
{
double[,] Acomb = new double[varsCount, varsCount];
double[] bcomb = new double[varsCount];
for (int i = 0; i < varsCount; i++)
{
for (int j = 0; j < varsCount; j++)
{
Acomb[i, j] = A[combination[i]][j];
}
bcomb[i] = b[combination[i]];
}
if (!Acomb.IsSingular())
{
var potentialV = Acomb.Solve(bcomb);
if (A.Dot(potentialV).Subtract(b).All(x => x <= EPS))
{
vertices.Add(potentialV);
}
}
}
if (vertices.Count() > 0)
{
return(new ConvexHull(vertices));
}
else
{
return(null);
}
}
