private List <double> FastCrossCorrelation(List <double> X1, List <double> X2, int N)
{
FastFourier ff = new FastFourier();
List <List <double> > x1 = new List <List <double> >();
List <List <double> > x2 = new List <List <double> >();
x1 = ff.fastFourier(X1, X1.Count);//iam in frequency domain now
x2 = ff.fastFourier(X2, X2.Count);
List <List <double> > result = new List <List <double> >();
List <double> finalResult = new List <double>();
List <List <double> > conj = new List <List <double> >();
List <List <double> > mul = new List <List <double> >();
if (convolution == true)
{
conj = x1;
}
else
{
conj = conjunction(x1);
}
for (int i = 0; i < N; i++) //multiplication
{
List <double> mulTmp = new List <double>();
mulTmp.Add(conj[i][0] * x2[i][0]);
mulTmp.Add((conj[i][1] * x2[i][0]) + (conj[i][1] * x2[i][1]) + (conj[i][0] * x2[i][1]));
mul.Add(mulTmp);
if (conj[i][1] != 0 && x2[i][1] != 0)
{
mul[i][0] += -(conj[i][1] * x2[i][1]);
}
}
Inverse_Fast_Fourier iff = new Inverse_Fast_Fourier();
result = iff.InvFastFourier(mul, N);
for (int i = 0; i < result.Count; i++)
{
result[i][0] = result[i][0] / N;
result[i][1] = result[i][1] / N;
}
for (int i = 0; i < result.Count; i++) //if you convolution
{
finalResult.Add(result[i][0]);
}
if (convolution == false)
{
for (int i = 0; i < N; i++)
{
finalResult[i] = finalResult[i] / N;
}
}
return(finalResult);
}
private void btnIFFT_Click(object sender, EventArgs e)
{
Inverse_Fast_Fourier i = new Inverse_Fast_Fourier();
i.Show();
}