} // forward
// * The 1-D reverse version of the Discrete Fourier Transform (DFT); The input
// * array arrFreq is organized by a class called Complex keeping real and
// * imaginary part of a complex number. The output arrTime is organized by the
// * same scheme.
// *
// * @date 23.11.2010 19:02:12
// * @author Christian Scheiblich
// * @param arrFreq
// * array of type Complex keeping the discrete fourier transform
// * coefficients
// * @return array of type Complex keeping coefficients of tiem domain
public override Complex[] reverse(Complex[] arrFreq)
{
int n = arrFreq.Length;
Complex[] arrTime = new Complex[n]; // result
for (int i = 0; i < n; i++)
{
arrTime[i] = new Complex(); // 0. , 0.
double arg = 2.0 * Math.PI * (double)i / (double)n;
for (int k = 0; k < n; k++)
{
double cos = Math.Cos(k * arg);
double sin = Math.Sin(k * arg);
double real = arrFreq[k].Re;
double imag = arrFreq[k].Im;
arrTime[i].Re += (real * cos - imag * sin);
arrTime[i].Im += (real * sin + imag * cos);
} // k
} // i
return(arrTime);
} // reverse
} // forward
// * The 1-D reverse version of the Discrete Fourier Transform (DFT); The input
// * array arrFreq is organized by a class called Complex keeping real and
// * imaginary part of a complex number. The output arrTime is organized by the
// * same scheme.
// *
// * @date 23.11.2010 19:02:12
// * @author Christian Scheiblich
// * @param arrFreq
// * array of type Complex keeping the discrete fourier transform
// * coefficients
// * @return array of type Complex keeping coefficients of tiem domain
public override Complex[] reverse(Complex[] arrFreq)
{
int n = arrFreq.Length;
Complex[] arrTime = new Complex[n]; // result
for(int i = 0; i < n; i++)
{
arrTime[i] = new Complex(); // 0. , 0.
double arg = 2.0 * Math.PI * (double)i / (double)n;
for(int k = 0; k < n; k++)
{
double cos = Math.Cos(k * arg);
double sin = Math.Sin(k * arg);
double real = arrFreq[k].Re;
double imag = arrFreq[k].Im;
arrTime[i].Re += (real * cos - imag * sin);
arrTime[i].Im += (real * sin + imag * cos);
} // k
} // i
return arrTime;
} // reverse
} // reverse
// * The 1-D forward version of the Discrete Fourier Transform (DFT); The input
// * array arrTime is organized by a class called Complex keeping real and
// * imaginary part of a complex number. The output arrFreq is organized by the
// * same scheme.
// *
// * @date 23.11.2010 18:57:34
// * @author Christian Scheiblich
// * @param arrTime
// * array of type Complex keeping coefficients of complex numbers
// * @return array of type Complex keeping the discrete fourier transform
// * coefficients
public override Complex[] forward(Complex[] arrTime)
{
int n = arrTime.Length;
Complex[] arrFreq = new Complex[n]; // result
for(int i = 0; i < n; i++)
{
arrFreq[i] = new Complex(); // 0. , 0.
double arg = -2.0 * Math.PI * (double)i / (double)n;
for(int k = 0; k < n; k++)
{
double cos = Math.Cos(k * arg);
double sin = Math.Sin(k * arg);
double real = arrTime[k].Re;
double imag = arrTime[k].Im;
arrFreq[i].Re += (real * cos - imag * sin);
arrFreq[i].Im += (real * sin + imag * cos);
} // k
arrFreq[i].Re *= (1.0 / (double)n);
arrFreq[i].Im *= (1.0 / (double)n);
} // i
return arrFreq;
} // forward
} // forward
// * Performs the reverse transform from frequency or Hilbert domain to time
// * domain for a given array depending on the used transform algorithm by
// * inheritance.
// *
// * @date 23.11.2010 19:17:59
// * @author Christian Scheiblich
// * @param arrFreq
// * coefficients of 1-D frequency or Hilbert domain
// * @return coefficients of 1-D time domain
public virtual Complex[] reverse(Complex[] arrFreq)
{
return null;
} // reverse
// * Performs the forward transform from time domain to frequency or Hilbert
// * domain for a given array depending on the used transform algorithm by
// * inheritance.
// *
// * @date 23.11.2010 19:17:46
// * @author Christian Scheiblich
// * @param arrTime
// * coefficients of 1-D time domain
// * @return coefficients of 1-D frequency or Hilbert domain
public virtual Complex[] forward(Complex[] arrTime)
{
return null;
} // forward
} // forward
// * Performs the reverse transform from frequency or Hilbert domain to time
// * domain for a given array depending on the used transform algorithm by
// * inheritance.
// *
// * @date 23.11.2010 19:19:33
// * @author Christian Scheiblich
// * @param arrFreq
// * coefficients of 1-D frequency or Hilbert domain
// * @return coefficients of 1-D time domain
public virtual Complex[] reverse(Complex[] arrFreq)
{
return ((BasicTransform)_transform).reverse(arrFreq);
} // reverse
} // reverse
// * Performs the forward transform from time domain to frequency or Hilbert
// * domain for a given array depending on the used transform algorithm by
// * inheritance.
// *
// * @date 23.11.2010 19:19:24
// * @author Christian Scheiblich
// * @param arrTime
// * coefficients of 1-D time domain
// * @return coefficients of 1-D frequency or Hilbert domain
public virtual Complex[] forward(Complex[] arrTime)
{
return ((BasicTransform)_transform).forward(arrTime);
} // forward
