/// <summary>
/// Returns a sorted list of EigenObjects sorted by their corresponding comparator implemention (eigenvalue in our case)
/// </summary>
/// <param name="Decomposition">Decomposition after solving the GEVP</param>
/// <returns></returns>
private List <EigenObject> GetSortedEigenObjects(IEigenvalueDecomposition Decomposition)
{
List <EigenObject> Res = new List <EigenObject>();
IMatrix Eigenvectors = Decomposition.EigenvectorMatrix;
for (int j = 0; j < Eigenvectors.Columns; j++)
{
EigenObject Eigen = new EigenObject();
double[] eigenvector = new double[Eigenvectors.Rows];
double magnitude = 0.0;
double eigenvalue = Decomposition.RealEigenvalues[j];
for (int i = 0; i < Eigenvectors.Rows; i++)
{
eigenvector[i] = Eigenvectors[i, j];
magnitude += Eigenvectors[i, j] * Eigenvectors[i, j];
}
magnitude = Math.Sqrt(magnitude);
Eigen.Magnitude = magnitude;
Eigen.Eigenvalue = eigenvalue;
Eigen.Eigenvector = eigenvector;
Res.Add(Eigen);
}
Res.Sort();
return(Res);
}
public int CompareTo(EigenObject Other)
{
if (Eigenvalue < Other.Eigenvalue)
{
return(1);
}
else if (this.Eigenvalue == Other.Eigenvalue)
{
return(0);
}
return(-1);
}
public int CompareTo(Object obj)
{
if (obj == null)
{
return(1);
}
EigenObject Other = obj as EigenObject;
if (Other != null)
{
return(CompareTo(Other));
}
else
{
throw new ArgumentException("Object is not an EigenFace");
}
}
/// <summary>
/// After solving the GEVP and having sorted the eigen values, we retrieve C-1 eigenvectors
/// </summary>
/// <param name="Eigens"> List of EigenObjects</param>
/// <param name="numVectors">Number of vector.</param>
/// <returns></returns>
private IMatrix GetLDABase(List <EigenObject> Eigens, int numVectors)
{
if (numVectors > (C - 1))
{
throw new ArgumentException("LDA Produces at MOST C-1 eigenvectors.");
}
if (Eigens == null || Eigens.Count < 1)
{
throw new ArgumentException("EigenObject list cannot be empty nor null!");
}
IMatrix Res = new Matrix(Eigens[0].Eigenvector.Length, numVectors);
for (int j = 0; j < numVectors; j++)
{
EigenObject Eg = Eigens[j];
for (int i = 0; i < Eg.Eigenvector.Length; i++)
{
Res[i, j] = Eg.Eigenvector[i] / Eg.Magnitude;
}
Console.WriteLine(j + " : " + Eg.Eigenvalue);
}
return(Res);
}
