simthlib::FastFourierTrans Class Reference

#include <fft.h>

List of all members.

Public Types
enum	FFT_type { FT = -1, IFT = 1 }
Public Member Functions
	FastFourierTrans ()
	~FastFourierTrans ()
void	FFT (const simth::Array< Complex > &inseq, simth::Array< Complex > *outseq, int space, int fac) const
void	IFFT (const simth::Array< Complex > &inseq, simth::Array< Complex > *outseq, int space, int fac) const

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Detailed Description

Fast Fourier transform. Complex sequences of type Sequence<Complex> or simth::SymSeq can be transformed with the FFT or IFFT into a new sequence. The maximal length of a sequence to be transformed is 4096.

In the FFT and IFFT functions the parameter em space is the oversampling factor of the original sample sequence. If this factor is e.g. 2, then only one out of two samples is used by the FFT. The result is a transformed sequence with half the number of samples containing all of the spectrum of the original sequence (the other samples are zero).

The parameter em fac is the oversampling factor of the transformed sequence. If this factor is e.g. 2, the transformed sequence contains double the number of samples as the original sequence.

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Member Enumeration Documentation

enum simthlib::FastFourierTrans::FFT_type

Flag for Fourier transform: FFT or IFFT. Enumeration values: FT  IFT

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Constructor & Destructor Documentation

simthlib::FastFourierTrans::FastFourierTrans (   )  [inline]

Class constructor.

simthlib::FastFourierTrans::~FastFourierTrans (   )  [inline]

Class destructor.

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Member Function Documentation

void simthlib::FastFourierTrans::FFT (  const simth::Array< Complex > &  inseq, simth::Array< Complex > *  outseq, int  space, int  fac )  const

FFT of a complex sequence.

void simthlib::FastFourierTrans::IFFT (  const simth::Array< Complex > &  inseq, simth::Array< Complex > *  outseq, int  space, int  fac )  const

IFFT of a complex sequence.

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