Contents


NAME

     dfft3i - initialize the array WSAVE, which is used  in  both
     DFFT3F and DFFT3B.

SYNOPSIS

     SUBROUTINE DFFT3I(M, N, K, WORK)

     INTEGER M, N, K
     DOUBLE PRECISION WORK(*)

     SUBROUTINE DFFT3I_64(M, N, K, WORK)

     INTEGER*8 M, N, K
     DOUBLE PRECISION WORK(*)

  F95 INTERFACE
     SUBROUTINE FFT3I(M, N, K, WORK)

     INTEGER :: M, N, K
     REAL(8), DIMENSION(:) :: WORK

     SUBROUTINE FFT3I_64(M, N, K, WORK)

     INTEGER(8) :: M, N, K
     REAL(8), DIMENSION(:) :: WORK

  C INTERFACE
     #include <sunperf.h>

     void dfft3i(int m, int n, int k, double *work);

     void dfft3i_64(long m, long n, long k, double *work);

ARGUMENTS

     M (input) Number of rows to be transformed.  M >= 0.

     N (input) Number of columns to be transformed.  N >= 0.

     K (input) Number of planes to be transformed.  K >= 0.

     WORK (input/output)
               On entry, an array of dimension (M + 2*(N +  K)  +
               30)  or  greater.   DFFT3I needs to be called only
               once  to  initialize  array  WORK  before  calling
               DFFT3F  and/or  DFFT3B  if M, N, K and WORK remain
               unchanged between these calls.   Thus,  subsequent
               transforms  or inverse transforms of same size can
               be obtained faster than the first  since  they  do
               not require initialization of the workspace.