SUBROUTINE user_3d_data_averaging( mode, variable )

!------------------------------------------------------------------------------!
! Current revisions:
! -----------------
! 
!
! Former revisions:
! -----------------
! $Id: user_3d_data_averaging.f90 667 2010-12-23 12:06:00Z helmke $
!
! 211 2008-11-11 04:46:24Z raasch
! Former file user_interface.f90 split into one file per subroutine
!
! Description:
! ------------
! Sum up and time-average user-defined output quantities as well as allocate
! the array necessary for storing the average.
!------------------------------------------------------------------------------!

    USE control_parameters
    USE indices
    USE user

    IMPLICIT NONE

    CHARACTER (LEN=*) ::  mode, variable

    INTEGER ::  i, j, k


    IF ( mode == 'allocate' )  THEN

       SELECT CASE ( TRIM( variable ) )

!
!--       Uncomment and extend the following lines, if necessary.
!--       The arrays for storing the user defined quantities (here u2_av) have
!--       to be declared and defined by the user!
!--       Sample for user-defined output:
!          CASE ( 'u2' )
!             IF ( .NOT. ALLOCATED( u2_av ) )  THEN
!                ALLOCATE( u2_av(nzb:nzt+1,nysg:nyng,nxlg:nxrg) )
!             ENDIF
!             u2_av = 0.0

          CASE DEFAULT
             CONTINUE

       END SELECT

    ELSEIF ( mode == 'sum' )  THEN

       SELECT CASE ( TRIM( variable ) )

!
!--       Uncomment and extend the following lines, if necessary.
!--       The arrays for storing the user defined quantities (here u2 and
!--       u2_av) have to be declared and defined by the user!
!--       Sample for user-defined output:
!          CASE ( 'u2' )
!             DO  i = nxlg, nxrg
!                DO  j = nysg, nyng
!                   DO  k = nzb, nzt+1
!                      u2_av(k,j,i) = u2_av(k,j,i) + u2(k,j,i)
!                   ENDDO
!                ENDDO
!             ENDDO

          CASE DEFAULT
             CONTINUE

       END SELECT

    ELSEIF ( mode == 'average' )  THEN

       SELECT CASE ( TRIM( variable ) )

!
!--       Uncomment and extend the following lines, if necessary.
!--       The arrays for storing the user defined quantities (here u2_av) have
!--       to be declared and defined by the user!
!--       Sample for user-defined output:
!          CASE ( 'u2' )
!             DO  i = nxlg, nxrg
!                DO  j = nysg, nyng
!                   DO  k = nzb, nzt+1
!                      u2_av(k,j,i) = u2_av(k,j,i) / REAL( average_count_3d )
!                   ENDDO
!                ENDDO
!             ENDDO

       END SELECT

    ENDIF


 END SUBROUTINE user_3d_data_averaging