fft_fft_multiple_complex

1 Description
2 Syntax
3 Parameters
4 Return
5 Examples
6 Remark
7 See Also
8 header to Include
9 Reference

Description

computes the discrete Fourier transforms of iSequences sequences of iSize complex data values.

Syntax

int fft_fft_multiple_complex( int iSequences, int iSize, double * vSigReal, double * vSigImag, FFT_SIGN iSign = FFT_FORWARD )

Parameters

iSequences: [input] the number of sequences.
iSize: [input] the number of data values in each sequence.
vSigReal: [modify] the real part of the input sequences, and the real part of the output Fourier transforms.
vSigImag: [modify] the imaginary part of the input sequences, and the imaginary part of the output Fourier transforms.
iSign: [input] the transformation to carry out; = FFT_FORWARD: FFT (by default); = FFT_BACKWARD: IFFT.

Return

Returns 0 for success or error codes for failure.

Examples

EX1

//Assume the current Worksheet has 3 sequences of complex data values stored in the first
//two columns. The first column contains the real part, and the second column imaginary
//part. This piece of code computers the discrete Fourier transform. The result is
//output into the third and the fourth columns. An inverse transform is performed,
//and the result is output into the fifth and the sixth columns.

#include <..\originlab\fft.h>    
void TEST_fft_fft_multiple_complex()
{
    int iSeq=3, iL=7, success;
    int n = iSeq*iL;
    Worksheet wks = Project.ActiveLayer();
    if(wks)
    {
        Dataset xx(wks, 0);
        Dataset yy(wks, 1);
        Dataset aa(wks, 2);
        aa.SetSize(n);
        Dataset bb(wks, 3);
        bb.SetSize(n);
        Dataset cc(wks, 4);
        cc.SetSize(n);    
        Dataset dd(wks, 5);
        dd.SetSize(n);            
        
        vector x = xx, y = yy;
    
        ///FT
        success = fft_fft_multiple_complex(iSeq, iL, x, y);
        aa = x;
        bb = y;
        
        ///IFT
        success = fft_fft_multiple_complex(iSeq, iL, x, y, FFT_BACKWARD);
        cc = x;
        dd = y;
    }
}