!CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
!                                                                       
!   FFTPACK 5.0                                                         
!                                                                       
!   Authors:  Paul N. Swarztrauber and Richard A. Valent                
!                                                                       
!   $Id: mradb3.f,v 1.2 2004/06/15 21:29:19 rodney Exp $                
!                                                                       
!CCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCCC
                                                                        
      SUBROUTINE MRADB3 (M,IDO,L1,CC,IM1,IN1,CH,IM2,IN2,WA1,WA2) 
      REAL       CC(IN1,IDO,3,L1)    ,CH(IN2,IDO,L1,3),                 &
     &           WA1(IDO)   ,WA2(IDO)                                   
!                                                                       
      M1D = (M-1)*IM1+1 
      M2S = 1-IM2 
      ARG=2.*4.*ATAN(1.0)/3. 
      TAUR=COS(ARG) 
      TAUI=SIN(ARG) 
      DO 101 K=1,L1 
          M2 = M2S 
          DO 1001 M1=1,M1D,IM1 
          M2 = M2+IM2 
         CH(M2,1,K,1) = CC(M1,1,1,K)+2.*CC(M1,IDO,2,K) 
         CH(M2,1,K,2) = CC(M1,1,1,K)+(2.*TAUR)*CC(M1,IDO,2,K)           &
     &   -(2.*TAUI)*CC(M1,1,3,K)                                        
         CH(M2,1,K,3) = CC(M1,1,1,K)+(2.*TAUR)*CC(M1,IDO,2,K)           &
     &   +2.*TAUI*CC(M1,1,3,K)                                          
 1001     CONTINUE 
  101 END DO 
      IF (IDO .EQ. 1) RETURN 
      IDP2 = IDO+2 
      DO 103 K=1,L1 
         DO 102 I=3,IDO,2 
            IC = IDP2-I 
               M2 = M2S 
               DO 1002 M1=1,M1D,IM1 
               M2 = M2+IM2 
        CH(M2,I-1,K,1) = CC(M1,I-1,1,K)+(CC(M1,I-1,3,K)+CC(M1,IC-1,2,K)) 
        CH(M2,I,K,1) = CC(M1,I,1,K)+(CC(M1,I,3,K)-CC(M1,IC,2,K)) 
        CH(M2,I-1,K,2) = WA1(I-2)*                                      &
     & ((CC(M1,I-1,1,K)+TAUR*(CC(M1,I-1,3,K)+CC(M1,IC-1,2,K)))-         &
     & (TAUI*(CC(M1,I,3,K)+CC(M1,IC,2,K))))                             &
     &                   -WA1(I-1)*                                     &
     & ((CC(M1,I,1,K)+TAUR*(CC(M1,I,3,K)-CC(M1,IC,2,K)))+               &
     & (TAUI*(CC(M1,I-1,3,K)-CC(M1,IC-1,2,K))))                         
            CH(M2,I,K,2) = WA1(I-2)*                                    &
     & ((CC(M1,I,1,K)+TAUR*(CC(M1,I,3,K)-CC(M1,IC,2,K)))+               &
     & (TAUI*(CC(M1,I-1,3,K)-CC(M1,IC-1,2,K))))                         &
     &                  +WA1(I-1)*                                      &
     & ((CC(M1,I-1,1,K)+TAUR*(CC(M1,I-1,3,K)+CC(M1,IC-1,2,K)))-         &
     & (TAUI*(CC(M1,I,3,K)+CC(M1,IC,2,K))))                             
              CH(M2,I-1,K,3) = WA2(I-2)*                                &
     & ((CC(M1,I-1,1,K)+TAUR*(CC(M1,I-1,3,K)+CC(M1,IC-1,2,K)))+         &
     & (TAUI*(CC(M1,I,3,K)+CC(M1,IC,2,K))))                             &
     &   -WA2(I-1)*                                                     &
     & ((CC(M1,I,1,K)+TAUR*(CC(M1,I,3,K)-CC(M1,IC,2,K)))-               &
     & (TAUI*(CC(M1,I-1,3,K)-CC(M1,IC-1,2,K))))                         
            CH(M2,I,K,3) = WA2(I-2)*                                    &
     & ((CC(M1,I,1,K)+TAUR*(CC(M1,I,3,K)-CC(M1,IC,2,K)))-               &
     & (TAUI*(CC(M1,I-1,3,K)-CC(M1,IC-1,2,K))))                         &
     &                 +WA2(I-1)*                                       &
     & ((CC(M1,I-1,1,K)+TAUR*(CC(M1,I-1,3,K)+CC(M1,IC-1,2,K)))+         &
     & (TAUI*(CC(M1,I,3,K)+CC(M1,IC,2,K))))                             
 1002          CONTINUE 
  102    CONTINUE 
  103 END DO 
      RETURN 
      END