Contents

• NAME
• SYNOPSIS
  • F95 INTERFACE
  • C INTERFACE
• ARGUMENTS

NAME

     dcosqi - initialize the array WSAVE, which is used  in  both
     COSQF and COSQB.

SYNOPSIS

     SUBROUTINE DCOSQI(N, WSAVE)

     INTEGER N
     DOUBLE PRECISION WSAVE(*)

     SUBROUTINE DCOSQI_64(N, WSAVE)

     INTEGER*8 N
     DOUBLE PRECISION WSAVE(*)

  F95 INTERFACE
     SUBROUTINE COSQI(N, WSAVE)

     INTEGER :: N
     REAL(8), DIMENSION(:) :: WSAVE

     SUBROUTINE COSQI_64(N, WSAVE)

     INTEGER(8) :: N
     REAL(8), DIMENSION(:) :: WSAVE

  C INTERFACE
     #include <sunperf.h>

     void dcosqi(int n, double *wsave);

     void dcosqi_64(long n, double *wsave);

ARGUMENTS

     N (input) Length of the sequence  to  be  transformed.   The
               method  is  most  efficient when N is a product of
               small primes.

     WSAVE (input)
               On entry, an array of dimension (3 * N  +  15)  or
               greater.   DCOSQI  needs to be called only once to
               initialize  WSAVE  before  calling  DCOSQF  and/or
               DCOSQB  if  N  and  WSAVE 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.