/// <summary>
/// Calculates the eigenvalues and the eigenfaces.
/// </summary>
private void CalculateEigenValues()
{
//25 = magicnumber, just needed to initialize double array
this._eigenValues = new double[25];
_s.Diagonal.ExportValues(ref this._eigenValues);
var eigenValuesPow = new double[_eigenValues.Length];
for (var i = 0; i < eigenValuesPow.Length; i++)
{
eigenValuesPow[i] = (double)Math.Pow((double)_eigenValues[i], -0.5);
}
this._eigenVectors.Clear();
for (var i = 0; i < eigenValuesPow.Length; i++)
{
var oneEigenVector = (ILArray <double>)_v.Subarray(new string[]
{
":",
i.ToString()
});
var oneFace = ILMath.multiply(_a, oneEigenVector);
var oneFace2 = ILMath.multiply(oneFace, eigenValuesPow[i]);
//25 = magicnumber, just needed to initialize double array
var eigenVectorArray = new double[25];
oneFace2.ExportValues(ref eigenVectorArray);
var distance = 0.0;
for (var j = 0; j < eigenVectorArray.Length; j++)
{
distance += Math.Pow((double)eigenVectorArray[j], 2.0);
}
distance = Math.Sqrt(distance);
for (var j = 0; j < eigenVectorArray.Length; j++)
{
eigenVectorArray[j] /= (float)distance;
}
this._eigenVectors.Add(eigenVectorArray);
}
this._eigenWeights.Clear();
for (var i = 0; i < this._vectorSet.Count; i++)
{
var existingWeight = this.GetEigenWeight((byte[])this._vectorSet[i], this._eigenVectors.Count);
this._eigenWeights.Add(existingWeight);
}
}