zfft2b (3p)

Name

zfft2b - compute a periodic sequence from its Fourier coefficients. The FFT operations are unnormalized, so a call of ZFFT2F followed by a call of ZFFT2B will multiply the input sequence by M*N.

Synopsis

SUBROUTINE ZFFT2B(M, N, A, LDA, WORK, LWORK)

DOUBLE COMPLEX A(LDA,*)
INTEGER M, N, LDA, LWORK
DOUBLE PRECISION WORK(*)

SUBROUTINE ZFFT2B_64(M, N, A, LDA, WORK, LWORK)

DOUBLE COMPLEX A(LDA,*)
INTEGER*8 M, N, LDA, LWORK
DOUBLE PRECISION WORK(*)




F95 INTERFACE
SUBROUTINE FFT2B(M, N, A, LDA, WORK, LWORK)

COMPLEX(8), DIMENSION(:,:) :: A
INTEGER :: M, N, LDA, LWORK
REAL(8), DIMENSION(:) :: WORK

SUBROUTINE FFT2B_64(M, N, A, LDA, WORK, LWORK)

COMPLEX(8), DIMENSION(:,:) :: A
INTEGER(8) :: M, N, LDA, LWORK
REAL(8), DIMENSION(:) :: WORK




C INTERFACE
#include <sunperf.h>

void  zfft2b(int m, int n, doublecomplex *a, int lda, double *work, int
lwork);

void zfft2b_64(long m, long  n,  doublecomplex  *a,  long  lda,  double
*work, long lwork);

Description

Oracle Solaris Studio Performance Library                           zfft2b(3P)



NAME
       zfft2b  -  compute  a  periodic sequence from its Fourier coefficients.
       The FFT operations are unnormalized, so a call of ZFFT2F followed by  a
       call of ZFFT2B will multiply the input sequence by M*N.


SYNOPSIS
       SUBROUTINE ZFFT2B(M, N, A, LDA, WORK, LWORK)

       DOUBLE COMPLEX A(LDA,*)
       INTEGER M, N, LDA, LWORK
       DOUBLE PRECISION WORK(*)

       SUBROUTINE ZFFT2B_64(M, N, A, LDA, WORK, LWORK)

       DOUBLE COMPLEX A(LDA,*)
       INTEGER*8 M, N, LDA, LWORK
       DOUBLE PRECISION WORK(*)




   F95 INTERFACE
       SUBROUTINE FFT2B(M, N, A, LDA, WORK, LWORK)

       COMPLEX(8), DIMENSION(:,:) :: A
       INTEGER :: M, N, LDA, LWORK
       REAL(8), DIMENSION(:) :: WORK

       SUBROUTINE FFT2B_64(M, N, A, LDA, WORK, LWORK)

       COMPLEX(8), DIMENSION(:,:) :: A
       INTEGER(8) :: M, N, LDA, LWORK
       REAL(8), DIMENSION(:) :: WORK




   C INTERFACE
       #include <sunperf.h>

       void  zfft2b(int m, int n, doublecomplex *a, int lda, double *work, int
                 lwork);

       void zfft2b_64(long m, long  n,  doublecomplex  *a,  long  lda,  double
                 *work, long lwork);



ARGUMENTS
       M (input) Number of rows to be transformed.  These subroutines are most
                 efficient when M is a product of small primes.  M >= 0.


       N (input) Number of columns to be transformed.  These  subroutines  are
                 most  efficient when N is a product of small primes.  N >= 0.


       A (input/output)
                 On entry, a two-dimensional array A(M,N)  that  contains  the
                 sequences to be transformed.


       LDA (input)
                 Leading  dimension  of  the  array  containing the data to be
                 transformed.  LDA >= M.


       WORK (input)
                 On entry, an array with dimension of at  least  LWORK.   WORK
                 must have been initialized by ZFFT2I.


       LWORK (input)
                 The dimension of the array WORK.  LWORK >= (4 * (M + N) + 30)




                                  7 Nov 2015                        zfft2b(3P)