VB.NET FFT Example

Imports System
Imports System.Globalization
Imports System.Threading
Imports System.Text

Imports CenterSpace.NMath.Core

Namespace CenterSpace.NMath.Core.Examples.VisualBasic

  ' .NET examples in VB.NET showing how to use the basic Fast Fourier Transform (FFT) Modulees.
  Module FFTExample

    Sub Main()

      '
      ' Simple example to compute a forward 1D real 1024 point FFT
      '

      ' Create some random signal data.
      Dim Rand As RandomNumberGenerator = New RandGenMTwist(4230987)
      Dim Data As New DoubleVector(1024, Rand)

      ' Compute the FFT
      ' This will create a complex conjugate symmetric packed result.
      Dim fft1024 As New DoubleForward1DFFT(1024)
      Dim FFTResult As DoubleVector = fft1024.FFT(Data)

      ' Ask the FFT instance for the correct reader, to unpacked the result.
      Dim Reader As DoubleSymmetricSignalReader = fft1024.GetSignalReader(Data)

      ' The reader provides random access to any element in the pack fft result.
      Dim ThirdElement As DoubleComplex = Reader(2)

      Console.WriteLine()
      Console.WriteLine("1D real forward 1024 point FFT computed.")
      Console.WriteLine("-----------------------------------" + Environment.NewLine)

      '
      ' Simple example to compute a backward 1D complex 1000 point FFT
      '

      ' Create some new random signal data.
      Dim CData As New DoubleComplexVector(1000, Rand)

      ' Create the 1D backward complex FFT instance
      Dim fft1000 As New DoubleComplexBackward1DFFT(1000)

      ' Compute the FFT
      ' Complex FFT's generated unpacked results.
      fft1000.FFTInPlace(CData)

      Console.WriteLine("1D complex backward 1000 point FFT computed.")
      Console.WriteLine("-----------------------------------" + Environment.NewLine)


      Console.WriteLine()
      Console.WriteLine("Finished. Press Enter Key.")
      Console.Read()

    End Sub
  End Module
End Namespace