# Transforms

## REAL TRIGONOMETRIC FFT

ROUTINE DESCRIPTION
FAST_DFT Computes the Discrete Fourier Transform of a rank-1 complex array, x.
FAST_2DFT Computes the Discrete Fourier Transform (2DFT) of a rank-2 complex array, x.
FAST_3DFT Computes the Discrete Fourier Transform (2DFT) of a rank-3 complex array, x.
FFTRF Computes the Fourier coefficients of a real periodic sequence.
FFTRB Computes the real periodic sequence from its Fourier coefficients.
FFTRI Computes parameters needed by FFTRF and FFTRB.

## COMPLEX EXPONENTIAL FFT

ROUTINE DESCRIPTION
FFTCF Computes the Fourier coefficients of a complex periodic sequence.
FFTCB Computes the complex periodic sequence from its Fourier coefficients.
FFTCI Computes parameters needed by FFTCF and FFTCB.

## REAL SINE AND COSINE FFTS

ROUTINE DESCRIPTION
FSINT Computes the discrete Fourier sine transformation of an odd sequence.
FSINI Computes parameters needed by FSINT.
FCOST Computes the discrete Fourier cosine transformation of an even sequence.
FCOSI Computes parameters needed by FCOST.

## REAL QUARTER SINE AND QUARTER COSINE FFTS

ROUTINE DESCRIPTION
QSINF Computes the coefficients of the sine Fourier transform with only odd wave numbers.
QSINB Computes a sequence from its sine Fourier coefficients with only odd wave numbers.
QSINI Computes parameters needed by QSINF and QSINB.
QCOSF Computes the coefficients of the cosine Fourier transform with only odd wave numbers.
QCOSB Computes a sequence from its cosine Fourier coefficients with only odd wave numbers.
QCOSI Computes parameters needed by QCOSF and QCOSB.

## TWO AND THREE DIMENSIONAL COMPLEX FFTS

ROUTINE DESCRIPTION
FFT2D Computes Fourier coefficients of a complex periodic two-dimensional array.
FFT2B Computes the inverse Fourier transform of a complex periodic two dimensional array.
FFT3F Computes Fourier coefficients of a complex periodic three-dimensional array.
FFT3B Computes the inverse Fourier transform of a complex periodic three-dimensional array.

## CONVOLUTIONS AND CORRELATIONS

ROUTINE DESCRIPTION
RCONV Computes the convolution of two real vectors.
CCONV Computes the convolution of two complex vectors.
RCORL Computes the correlation of two real vectors.
CCORL Computes the correlation of two complex vectors.

## LAPLACE TRANSFORM

ROUTINE DESCRIPTION
INLAP Computes the inverse Laplace transform of a complex function.
SINLP Computes the inverse Laplace transform of a complex function.