org.javaseis.fft
Interface IFFT

All Known Implementing Classes:

SeisFft

public interface IFFT

Nested Class Summary

static class	IFFT.Scale
static class	IFFT.Type

Method Summary

void	complexForward(float[] cx) Perform an in-place complex-to-complex forward transform
void	complexForward(float[] cx, float[] cy)
void	complexForward(float[] cx, int offset)
void	complexForward(float[] cx, int xoff, float[] cy, int yoff)
void	complexInverse(float[] cy) Perform an in-place complex-to-complex inverse transform
void	complexInverse(float[] cy, float[] cx)
void	complexInverse(float[] cy, int offset)
void	complexInverse(float[] cy, int yoff, float[] cx, int xoff)
void	complexToReal(float[] cy) Perform an in-place complex-to-real inverse transform
void	complexToReal(float[] cy, float[] rx)
void	complexToReal(float[] cy, int offset)
void	complexToReal(float[] cy, int yoff, float[] rx, int xoff)
int	getArrayLength() Return the length of the transform array in 32 bit words (floats)
int	getLength() Return the transform length
void	realToComplex(float[] rx) Perform an in-place real to complex forward transform
void	realToComplex(float[] rx, float[] cy) Out-of-place transforms that do not modify the input data
void	realToComplex(float[] rx, int offset) In place transforms with optional offset
void	realToComplex(float[] rx, int xoff, float[] cy, int yoff) Out-of-place transforms that do not modify the input data
void	setFftParms(int length, IFFT.Type type, IFFT.Scale scale, float padPercent, int forwardSign) Set transform parameters

Method Detail

complexForward

void complexForward(float[] cx)

Perform an in-place complex-to-complex forward transform

Parameters:

cx - input complex data, output complex forward transform

complexForward

void complexForward(float[] cx,
                    float[] cy)

complexForward

void complexForward(float[] cx,
                    int offset)

complexForward

void complexForward(float[] cx,
                    int xoff,
                    float[] cy,
                    int yoff)

complexInverse

void complexInverse(float[] cy)

Perform an in-place complex-to-complex inverse transform

Parameters:

cy - input complex transform, output complex inverse transform

complexInverse

void complexInverse(float[] cy,
                    float[] cx)

complexInverse

void complexInverse(float[] cy,
                    int offset)

complexInverse

void complexInverse(float[] cy,
                    int yoff,
                    float[] cx,
                    int xoff)

complexToReal

void complexToReal(float[] cy)

Perform an in-place complex-to-real inverse transform

Parameters:

cy - input complex Fourier transform, output real inverse Fourier transform

complexToReal

void complexToReal(float[] cy,
                   float[] rx)

complexToReal

void complexToReal(float[] cy,
                   int offset)

complexToReal

void complexToReal(float[] cy,
                   int yoff,
                   float[] rx,
                   int xoff)

getArrayLength

int getArrayLength()

Return the length of the transform array in 32 bit words (floats)

Returns:

transform array length

getLength

int getLength()

Return the transform length

Returns:

transform length

realToComplex

void realToComplex(float[] rx)

Perform an in-place real to complex forward transform

Parameters:

rx - input real data to be transformed, output complex Fourier transform

realToComplex

void realToComplex(float[] rx,
                   float[] cy)

Out-of-place transforms that do not modify the input data

Parameters:

a - input array to be transformed

b - output array containing transform

realToComplex

void realToComplex(float[] rx,
                   int offset)

In place transforms with optional offset

Parameters:

a - input array to be transformed

offset - starting index for transform within the array

realToComplex

void realToComplex(float[] rx,
                   int xoff,
                   float[] cy,
                   int yoff)

Out-of-place transforms that do not modify the input data

Parameters:

a - input array to be transformed

aindex - start index of the data in the input array

b - output array containing transform

bindex - start index for placing the output data

setFftParms

void setFftParms(int length,
                 IFFT.Type type,
                 IFFT.Scale scale,
                 float padPercent,
                 int forwardSign)

Set transform parameters

Parameters:

length - length of the input data to be transformed

type - transform type from the enum SeisFft.Type.REAL or SeisFft.Type.COMPLEX

scale - transform scaling from the enum SeisFft.Scale.NONE, INVERSE, or SYMMETRIC

padPercent - requested zero padding as a percentage of the input length

isign - forward transform sign, -1 or +1