scfftm1dui(3F)

NAME
     scfftm1dui, dzfftm1dui - initialize the coefficient array for real-to-
     complex Multiple 1D FFT modules.

SYNOPSYS
     FORTRAN SPECIFICATION
     subroutine SCFFTM1DUI( n, coeff )
     integer                  n
     real           coeff(n+15)

     subroutine DZFFTM1DUI( n, coeff )
     integer                  n
     real*8              coeff(n+15)

     C SPECIFICATION
     #include <fft.h>
     float *scfftm1dui( int n, float *coeff);

     double *dzfftm1dui( int n, double *coeff);


DESCRIPTION
     Initialize, the coefficient array which is used in the Multiple 1D FFT
     modules.  This array contains the different twiddle factors and the
     factorization of N into prime numbers.
     As the FFT modules scfftm1d or dzfftm1d only read the coeff array, it may
     be reused as long as necessary once it has been initialized.

     In C, if ptr is NULL, scfftm1dui or dzfftm1dui returns a pointer to an
     allocated buffer.

     SCFFTM1DUI should be used to initialize the coefficient array before any
     call to SCFFTM1DU
     DZFFTM1DUI should be used to initialize the coefficient array before any
     call to DZFFTM1DU

PARAMETERS
     N - Integer. Specifies the length of the sequence to be transformed.
      Unchanged on exit.

     COEFF - Array (C or Fortran) or NULL pointer(C).

Example of Calling Sequence
     Initializing a coefficient array for real-to-complex FFTs of size 200.

     Fortran :
          real coeff(200+15)
          call scfftm1dui( 200, coeff)

     C :
          #include <fft.h>
          float *coeff;
         coeff = scfftm1dui( 200, NULL);

SEE ALSO
          fft, scfftm1du, dzfftm1du