C     SUBROUTINE CFFTI(N,WSAVE)                                                 
C                                                                               
C     SUBROUTINE CFFTI INITIALIZES THE ARRAY WSAVE WHICH IS USED IN             
C     BOTH CFFTF AND CFFTB. THE PRIME FACTORIZATION OF N TOGETHER WITH          
C     A TABULATION OF THE TRIGONOMETRIC FUNCTIONS ARE COMPUTED AND              
C     STORED IN WSAVE.                                                          
C                                                                               
C     INPUT PARAMETER                                                           
C                                                                               
C     N       THE LENGTH OF THE SEQUENCE TO BE TRANSFORMED                      
C                                                                               
C     OUTPUT PARAMETER                                                          
C                                                                               
C     WSAVE   A WORK ARRAY WHICH MUST BE DIMENSIONED AT LEAST 4*N+15            
C             THE SAME WORK ARRAY CAN BE USED FOR BOTH CFFTF AND CFFTB          
C             AS LONG AS N REMAINS UNCHANGED. DIFFERENT WSAVE ARRAYS            
C             ARE REQUIRED FOR DIFFERENT VALUES OF N. THE CONTENTS OF           
C             WSAVE MUST NOT BE CHANGED BETWEEN CALLS OF CFFTF OR CFFTB.        
C                                                                               
      SUBROUTINE CFFTI (N,WSAVE)                                                
      DIMENSION       WSAVE(*)                                                  
C                                                                               
      IF (N .EQ. 1) RETURN                                                      
      IW1 = N+N+1                                                               
      IW2 = IW1+N+N                                                             
      CALL CFFTI1 (N,WSAVE(IW1),WSAVE(IW2))                                     
      RETURN                                                                    
      END