SUBROUTINE data_output_mask( av )

!--------------------------------------------------------------------------------!
! This file is part of PALM.
!
! PALM is free software: you can redistribute it and/or modify it under the terms
! of the GNU General Public License as published by the Free Software Foundation,
! either version 3 of the License, or (at your option) any later version.
!
! PALM is distributed in the hope that it will be useful, but WITHOUT ANY
! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
! A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
!
! You should have received a copy of the GNU General Public License along with
! PALM. If not, see <http://www.gnu.org/licenses/>.
!
! Copyright 1997-2012  Leibniz University Hannover
!--------------------------------------------------------------------------------!
!
! Current revisions:
! -----------------
! 
!
! Former revisions:
! -----------------
! $Id: data_output_mask.f90 1093 2013-02-02 12:58:49Z witha $
!
! 1092 2013-02-02 11:24:22Z raasch
! unused variables removed
!
! 1036 2012-10-22 13:43:42Z raasch
! code put under GPL (PALM 3.9)
!
! 1031 2012-10-19 14:35:30Z raasch
! netCDF4 without parallel file support implemented
!
! 1007 2012-09-19 14:30:36Z franke
! Bugfix: calculation of pr must depend on the particle weighting factor,
! missing calculation of ql_vp added
!
! 771 2011-10-27 10:56:21Z heinze
! +lpt
!
! 667 2010-12-23 12:06:00Z suehring/gryschka
! Calls of exchange_horiz are modified.
!
! 564 2010-09-30 13:18:59Z helmke
! start number of mask output files changed to 201, netcdf message identifiers
! of masked output changed, palm message identifiers of masked output changed 
!
! 493 2010-03-01 08:30:24Z raasch
! netcdf_format_mask* and format_parallel_io replaced by netcdf_data_format
!
! 475 2010-02-04 02:26:16Z raasch
! Bugfix in serial branch: arguments from array local_pf removed in N90_PUT_VAR
!
! 410 2009-12-04 17:05:40Z letzel
! Initial version
!
! Description:
! ------------
! Masked data output in netCDF format for current mask (current value of mid).
!------------------------------------------------------------------------------!

#if defined( __netcdf )
    USE arrays_3d
    USE averaging
    USE cloud_parameters
    USE control_parameters
    USE cpulog
    USE grid_variables
    USE indices
    USE interfaces
    USE netcdf
    USE netcdf_control
    USE particle_attributes
    USE pegrid

    IMPLICIT NONE

    INTEGER ::  av, ngp, i, if, j, k, n, psi, sender, &
                ind(6)
    LOGICAL ::  found, resorted
    REAL    ::  mean_r, s_r3, s_r4
    REAL, DIMENSION(:,:,:), ALLOCATABLE ::  local_pf
#if defined( __parallel )
    REAL, DIMENSION(:,:,:), ALLOCATABLE ::  total_pf
#endif
    REAL, DIMENSION(:,:,:), POINTER ::  to_be_resorted

!
!-- Return, if nothing to output
    IF ( domask_no(mid,av) == 0 )  RETURN

    CALL cpu_log (log_point(49),'data_output_mask','start')

!
!-- Open output file.
    IF ( netcdf_output  .AND.  ( myid == 0  .OR.  netcdf_data_format > 4 ) ) &
    THEN
       CALL check_open( 200+mid+av*max_masks )
    ENDIF 

!
!-- Allocate total and local output arrays.
#if defined( __parallel )
    IF ( myid == 0 )  THEN
       ALLOCATE( total_pf(mask_size(mid,1),mask_size(mid,2),mask_size(mid,3)) )
    ENDIF
#endif
    ALLOCATE( local_pf(mask_size_l(mid,1),mask_size_l(mid,2), &
                       mask_size_l(mid,3)) )

!
!-- Update the netCDF time axis.
    domask_time_count(mid,av) = domask_time_count(mid,av) + 1
    IF ( netcdf_output  .AND.  ( myid == 0  .OR.  netcdf_data_format > 4 ) ) &
    THEN
       nc_stat = NF90_PUT_VAR( id_set_mask(mid,av), id_var_time_mask(mid,av), &
                               (/ simulated_time /),                          &
                               start = (/ domask_time_count(mid,av) /),       &
                               count = (/ 1 /) )
       CALL handle_netcdf_error( 'data_output_mask', 460 )
    ENDIF

!
!-- Loop over all variables to be written.
    if = 1

    DO  WHILE ( domask(mid,av,if)(1:1) /= ' ' )
!
!--    Reallocate local_pf on PE 0 since its shape changes during MPI exchange
       IF ( netcdf_data_format < 5   .AND.  myid == 0  .AND.  if > 1 )  THEN
          DEALLOCATE( local_pf )
          ALLOCATE( local_pf(mask_size_l(mid,1),mask_size_l(mid,2), &
                             mask_size_l(mid,3)) )
       ENDIF
!
!--    Store the variable chosen.
       resorted = .FALSE.
       SELECT CASE ( TRIM( domask(mid,av,if) ) )

          CASE ( 'e' )
             IF ( av == 0 )  THEN
                to_be_resorted => e
             ELSE
                to_be_resorted => e_av
             ENDIF

          CASE ( 'lpt' )
             IF ( av == 0 )  THEN
                to_be_resorted => pt
             ELSE
                to_be_resorted => lpt_av
             ENDIF

          CASE ( 'p' )
             IF ( av == 0 )  THEN
                to_be_resorted => p
             ELSE
                to_be_resorted => p_av
             ENDIF

          CASE ( 'pc' )  ! particle concentration (requires ghostpoint exchange)
             IF ( av == 0 )  THEN
                tend = prt_count
                CALL exchange_horiz( tend, nbgp )
                DO  i = 1, mask_size_l(mid,1)
                   DO  j = 1, mask_size_l(mid,2)
                      DO  k = 1, mask_size_l(mid,3)
                         local_pf(i,j,k) =  tend(mask_k(mid,k), &
                                   mask_j(mid,j),mask_i(mid,i))
                      ENDDO
                   ENDDO
                ENDDO
                resorted = .TRUE.
             ELSE
                CALL exchange_horiz( pc_av, nbgp )
                to_be_resorted => pc_av
             ENDIF

          CASE ( 'pr' )  ! mean particle radius
             IF ( av == 0 )  THEN
                DO  i = nxl, nxr
                   DO  j = nys, nyn
                      DO  k = nzb, nzt+1
                         psi = prt_start_index(k,j,i)
                         s_r3 = 0.0
                         s_r4 = 0.0
                         DO  n = psi, psi+prt_count(k,j,i)-1
                            s_r3 = s_r3 + particles(n)%radius**3 * &
                                          particles(n)%weight_factor
                            s_r4 = s_r4 + particles(n)%radius**4 * &
                                          particles(n)%weight_factor
                         ENDDO
                         IF ( s_r3 /= 0.0 )  THEN
                            mean_r = s_r4 / s_r3
                         ELSE
                            mean_r = 0.0
                         ENDIF
                         tend(k,j,i) = mean_r
                      ENDDO
                   ENDDO
                ENDDO
                CALL exchange_horiz( tend, nbgp )
                DO  i = 1, mask_size_l(mid,1)
                   DO  j = 1, mask_size_l(mid,2)
                      DO  k = 1, mask_size_l(mid,3)
                         local_pf(i,j,k) =  tend(mask_k(mid,k), &
                                   mask_j(mid,j),mask_i(mid,i))
                      ENDDO
                   ENDDO
                ENDDO
                resorted = .TRUE.
             ELSE
                CALL exchange_horiz( pr_av, nbgp )
                to_be_resorted => pr_av
             ENDIF

          CASE ( 'pt' )
             IF ( av == 0 )  THEN
                IF ( .NOT. cloud_physics ) THEN
                   to_be_resorted => pt
                ELSE
                   DO  i = 1, mask_size_l(mid,1)
                      DO  j = 1, mask_size_l(mid,2)
                         DO  k = 1, mask_size_l(mid,3)
                            local_pf(i,j,k) =  &
                                 pt(mask_k(mid,k),mask_j(mid,j),mask_i(mid,i)) &
                                 + l_d_cp * pt_d_t(mask_k(mid,k)) * &
                                   ql(mask_k(mid,k),mask_j(mid,j),mask_i(mid,i))
                         ENDDO
                      ENDDO
                   ENDDO
                   resorted = .TRUE.
                ENDIF
             ELSE
                to_be_resorted => pt_av
             ENDIF

          CASE ( 'q' )
             IF ( av == 0 )  THEN
                to_be_resorted => q
             ELSE
                to_be_resorted => q_av
             ENDIF

          CASE ( 'ql' )
             IF ( av == 0 )  THEN
                to_be_resorted => ql
             ELSE
                to_be_resorted => ql_av
             ENDIF

          CASE ( 'ql_c' )
             IF ( av == 0 )  THEN
                to_be_resorted => ql_c
             ELSE
                to_be_resorted => ql_c_av
             ENDIF

          CASE ( 'ql_v' )
             IF ( av == 0 )  THEN
                to_be_resorted => ql_v
             ELSE
                to_be_resorted => ql_v_av
             ENDIF

          CASE ( 'ql_vp' )
             IF ( av == 0 )  THEN
                DO  i = nxl, nxr
                   DO  j = nys, nyn
                      DO  k = nzb, nz_do3d
                         psi = prt_start_index(k,j,i)
                         DO  n = psi, psi+prt_count(k,j,i)-1
                            tend(k,j,i) = tend(k,j,i) + &
                                          particles(n)%weight_factor / &
                                          prt_count(k,j,i)
                         ENDDO
                      ENDDO
                   ENDDO
                ENDDO
                CALL exchange_horiz( tend, nbgp )
                DO  i = 1, mask_size_l(mid,1)
                   DO  j = 1, mask_size_l(mid,2)
                      DO  k = 1, mask_size_l(mid,3)
                         local_pf(i,j,k) =  tend(mask_k(mid,k), &
                                   mask_j(mid,j),mask_i(mid,i))
                      ENDDO
                   ENDDO
                ENDDO
                resorted = .TRUE.
             ELSE
                CALL exchange_horiz( ql_vp_av, nbgp )
                to_be_resorted => ql_vp_av
             ENDIF

          CASE ( 'qv' )
             IF ( av == 0 )  THEN
                DO  i = 1, mask_size_l(mid,1)
                   DO  j = 1, mask_size_l(mid,2)
                      DO  k = 1, mask_size_l(mid,3)
                         local_pf(i,j,k) =  &
                              q(mask_k(mid,k),mask_j(mid,j),mask_i(mid,i)) -  &
                              ql(mask_k(mid,k),mask_j(mid,j),mask_i(mid,i))
                      ENDDO
                   ENDDO
                ENDDO
                resorted = .TRUE.
             ELSE
                to_be_resorted => qv_av
             ENDIF

          CASE ( 'rho' )
             IF ( av == 0 )  THEN
                to_be_resorted => rho
             ELSE
                to_be_resorted => rho_av
             ENDIF

          CASE ( 's' )
             IF ( av == 0 )  THEN
                to_be_resorted => q
             ELSE
                to_be_resorted => s_av
             ENDIF

          CASE ( 'sa' )
             IF ( av == 0 )  THEN
                to_be_resorted => sa
             ELSE
                to_be_resorted => sa_av
             ENDIF

          CASE ( 'u' )
             IF ( av == 0 )  THEN
                to_be_resorted => u
             ELSE
                to_be_resorted => u_av
             ENDIF

          CASE ( 'v' )
             IF ( av == 0 )  THEN
                to_be_resorted => v
             ELSE
                to_be_resorted => v_av
             ENDIF

          CASE ( 'vpt' )
             IF ( av == 0 )  THEN
                to_be_resorted => vpt
             ELSE
                to_be_resorted => vpt_av
             ENDIF

          CASE ( 'w' )
             IF ( av == 0 )  THEN
                to_be_resorted => w
             ELSE
                to_be_resorted => w_av
             ENDIF

          CASE DEFAULT
!
!--          User defined quantity
             CALL user_data_output_mask(av, domask(mid,av,if), found, local_pf )
             resorted = .TRUE.

             IF ( .NOT. found )  THEN
                WRITE ( message_string, * ) 'no output available for: ', &
                                            TRIM( domask(mid,av,if) )
                CALL message( 'data_output_mask', 'PA0327', 0, 0, 0, 6, 0 )
             ENDIF

       END SELECT

!
!--    Resort the array to be output, if not done above
       IF ( .NOT. resorted )  THEN
          DO  i = 1, mask_size_l(mid,1)
             DO  j = 1, mask_size_l(mid,2)
                DO  k = 1, mask_size_l(mid,3)
                   local_pf(i,j,k) =  to_be_resorted(mask_k(mid,k), &
                                      mask_j(mid,j),mask_i(mid,i))
                ENDDO
             ENDDO
          ENDDO
       ENDIF

!
!--    I/O block. I/O methods are implemented
!--    (1) for parallel execution
!--     a. with netCDF 4 parallel I/O-enabled library
!--     b. with netCDF 3 library
!--    (2) for serial execution.
!--    The choice of method depends on the correct setting of preprocessor
!--    directives __parallel and __netcdf4_parallel as well as on the parameter
!--    netcdf_data_format.
#if defined( __parallel )
#if defined( __netcdf4_parallel )
       IF ( netcdf_data_format > 4 )  THEN
!
!--       (1) a. Parallel I/O using netCDF 4 (not yet tested)
          nc_stat = NF90_PUT_VAR( id_set_mask(mid,av),  &
               id_var_domask(mid,av,if),  &
               local_pf,  &
               start = (/ mask_start_l(mid,1), mask_start_l(mid,2),  &
                          mask_start_l(mid,3), domask_time_count(mid,av) /),  &
               count = (/ mask_size_l(mid,1), mask_size_l(mid,2),  &
                          mask_size_l(mid,3), 1 /) )
          CALL handle_netcdf_error( 'data_output_mask', 461 )
       ELSE
#endif
!
!--       (1) b. Conventional I/O only through PE0
!--       PE0 receives partial arrays from all processors of the respective mask
!--       and outputs them. Here a barrier has to be set, because otherwise 
!--       "-MPI- FATAL: Remote protocol queue full" may occur.
          CALL MPI_BARRIER( comm2d, ierr )

          ngp = mask_size_l(mid,1) * mask_size_l(mid,2) * mask_size_l(mid,3)
          IF ( myid == 0 )  THEN
!
!--          Local array can be relocated directly.
             total_pf( &
               mask_start_l(mid,1):mask_start_l(mid,1)+mask_size_l(mid,1)-1, &
               mask_start_l(mid,2):mask_start_l(mid,2)+mask_size_l(mid,2)-1, &
               mask_start_l(mid,3):mask_start_l(mid,3)+mask_size_l(mid,3)-1 ) &
               = local_pf
!
!--          Receive data from all other PEs.
             DO  n = 1, numprocs-1
!
!--             Receive index limits first, then array.
!--             Index limits are received in arbitrary order from the PEs.
                CALL MPI_RECV( ind(1), 6, MPI_INTEGER, MPI_ANY_SOURCE, 0,  &
                     comm2d, status, ierr )
!
!--             Not all PEs have data for the mask
                IF ( ind(1) /= -9999 )  THEN
                   ngp = ( ind(2)-ind(1)+1 ) * (ind(4)-ind(3)+1 ) *  &
                         ( ind(6)-ind(5)+1 )
                   sender = status(MPI_SOURCE)
                   DEALLOCATE( local_pf )
                   ALLOCATE(local_pf(ind(1):ind(2),ind(3):ind(4),ind(5):ind(6)))
                   CALL MPI_RECV( local_pf(ind(1),ind(3),ind(5)), ngp,  &
                        MPI_REAL, sender, 1, comm2d, status, ierr )
                   total_pf(ind(1):ind(2),ind(3):ind(4),ind(5):ind(6)) &
                        = local_pf
                ENDIF
             ENDDO

             nc_stat = NF90_PUT_VAR( id_set_mask(mid,av),  &
                  id_var_domask(mid,av,if), total_pf, &
                  start = (/ 1, 1, 1, domask_time_count(mid,av) /), &
                  count = (/ mask_size(mid,1), mask_size(mid,2), &
                             mask_size(mid,3), 1 /) )
             CALL handle_netcdf_error( 'data_output_mask', 462 )

          ELSE
!
!--          If at least part of the mask resides on the PE, send the index
!--          limits for the target array, otherwise send -9999 to PE0.
             IF ( mask_size_l(mid,1) > 0 .AND.  mask_size_l(mid,2) > 0 .AND. &
                  mask_size_l(mid,3) > 0  ) &
                  THEN
                ind(1) = mask_start_l(mid,1)
                ind(2) = mask_start_l(mid,1) + mask_size_l(mid,1) - 1
                ind(3) = mask_start_l(mid,2)
                ind(4) = mask_start_l(mid,2) + mask_size_l(mid,2) - 1
                ind(5) = mask_start_l(mid,3)
                ind(6) = mask_start_l(mid,3) + mask_size_l(mid,3) - 1
             ELSE
                ind(1) = -9999; ind(2) = -9999
                ind(3) = -9999; ind(4) = -9999
                ind(5) = -9999; ind(6) = -9999
             ENDIF
             CALL MPI_SEND( ind(1), 6, MPI_INTEGER, 0, 0, comm2d, ierr )
!
!--          If applicable, send data to PE0.
             IF ( ind(1) /= -9999 )  THEN
                CALL MPI_SEND( local_pf(1,1,1), ngp, MPI_REAL, 0, 1, comm2d, &
                     ierr )
             ENDIF
          ENDIF
!
!--       A barrier has to be set, because otherwise some PEs may proceed too
!--       fast so that PE0 may receive wrong data on tag 0.
          CALL MPI_BARRIER( comm2d, ierr )
#if defined( __netcdf4_parallel )
       ENDIF
#endif
#else
!
!--    (2) For serial execution of PALM, the single processor (PE0) holds all
!--    data and writes them directly to file.
       nc_stat = NF90_PUT_VAR( id_set_mask(mid,av),  &
            id_var_domask(mid,av,if),       &
            local_pf, &
            start = (/ 1, 1, 1, domask_time_count(mid,av) /), &
            count = (/ mask_size_l(mid,1), mask_size_l(mid,2), &
                       mask_size_l(mid,3), 1 /) )
       CALL handle_netcdf_error( 'data_output_mask', 463 )
#endif

       if = if + 1

    ENDDO

!
!-- Deallocate temporary arrays.
    DEALLOCATE( local_pf )
#if defined( __parallel )
    IF ( myid == 0 )  THEN
       DEALLOCATE( total_pf )
    ENDIF
#endif


    CALL cpu_log (log_point(49),'data_output_mask','stop','nobarrier')
#endif

 END SUBROUTINE data_output_mask