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source: palm/trunk/SOURCE/init_pegrid.f90 @ 4477

Last change on this file since 4477 was 4461, checked in by raasch, 5 years ago
extensions to allow usage of alternative communicators in exchange_horiz
Property svn:keywords set to `Id`
File size: 53.6 KB

Rev	Line
[1682]	1	!> @file init_pegrid.f90
[2000]	2	!------------------------------------------------------------------------------!
[2696]	3	! This file is part of the PALM model system.
[1036]	4	!
[2000]	5	! PALM is free software: you can redistribute it and/or modify it under the
	6	! terms of the GNU General Public License as published by the Free Software
	7	! Foundation, either version 3 of the License, or (at your option) any later
	8	! version.
[1036]	9	!
	10	! PALM is distributed in the hope that it will be useful, but WITHOUT ANY
	11	! WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
	12	! A PARTICULAR PURPOSE. See the GNU General Public License for more details.
	13	!
	14	! You should have received a copy of the GNU General Public License along with
	15	! PALM. If not, see <http://www.gnu.org/licenses/>.
	16	!
[4360]	17	! Copyright 1997-2020 Leibniz Universitaet Hannover
[2000]	18	!------------------------------------------------------------------------------!
[1036]	19	!
[254]	20	! Current revisions:
[1322]	21	! ------------------
[2201]	22	!
[3553]	23	!
[1321]	24	! Former revisions:
	25	! -----------------
	26	! $Id: init_pegrid.f90 4461 2020-03-12 16:51:59Z maronga $
[4461]	27	! communicator configurations for four virtual pe grids defined
	28	!
	29	! 4444 2020-03-05 15:59:50Z raasch
[4444]	30	! bugfix: cpp-directives for serial mode added
	31	!
	32	! 4360 2020-01-07 11:25:50Z suehring
[4301]	33	! changed message PA0467
	34	!
	35	! 4264 2019-10-15 16:00:23Z scharf
[4264]	36	! corrected error message string
	37	!
	38	! 4241 2019-09-27 06:32:47Z raasch
[4241]	39	! Check added to ensure that subdomain grid has at least the size as given by the number
	40	! of ghost points
	41	!
	42	! 4182 2019-08-22 15:20:23Z scharf
[4182]	43	! Corrected "Former revisions" section
	44	!
	45	! 4045 2019-06-21 10:58:47Z raasch
[4045]	46	! bugfix: kind attribute added to nint function to allow for large integers which may appear in
	47	! case of default recycling width and small grid spacings
	48	!
	49	! 3999 2019-05-23 16:09:37Z suehring
[3999]	50	! Spend 3 ghost points also in case of pw-scheme when nesting is applied
	51	!
	52	! 3897 2019-04-15 11:51:14Z suehring
[3897]	53	! Minor revision of multigrid check; give warning instead of an abort.
	54	!
	55	! 3890 2019-04-12 15:59:20Z suehring
[3890]	56	! Check if grid coarsening is possible on subdomain, in order to avoid that
	57	! multigrid approach effectively reduces to a Gauss-Seidel scheme.
	58	!
	59	! 3885 2019-04-11 11:29:34Z kanani
[3885]	60	! Changes related to global restructuring of location messages and introduction
	61	! of additional debug messages
	62	!
	63	! 3884 2019-04-10 13:31:55Z Giersch
[3884]	64	! id_recycling is only calculated in case of tubulent inflow
	65	!
	66	! 3761 2019-02-25 15:31:42Z raasch
[3761]	67	! unused variable removed
	68	!
	69	! 3655 2019-01-07 16:51:22Z knoop
[3553]	70	! variables documented
[2259]	71	!
[4182]	72	! Revision 1.1 1997/07/24 11:15:09 raasch
	73	! Initial revision
	74	!
	75	!
[1]	76	! Description:
	77	! ------------
[1682]	78	!> Determination of the virtual processor topology (if not prescribed by the
	79	!> user)and computation of the grid point number and array bounds of the local
	80	!> domains.
[2696]	81	!> @todo: remove MPI-data types for 2D exchange on coarse multigrid level (not
	82	!> used any more)
[1]	83	!------------------------------------------------------------------------------!
[1682]	84	SUBROUTINE init_pegrid
	85
[1]	86
[1320]	87	USE control_parameters, &
[3182]	88	ONLY: bc_dirichlet_l, bc_dirichlet_n, bc_dirichlet_r, bc_dirichlet_s, &
	89	bc_lr, bc_ns, bc_radiation_l, bc_radiation_n, bc_radiation_r, &
[4444]	90	bc_radiation_s, &
[3241]	91	grid_level, grid_level_count, maximum_grid_level, &
[4444]	92	message_string, mg_switch_to_pe0_level, &
	93	psolver
[1]	94
[4444]	95
	96	#if defined( __parallel )
	97	USE control_parameters, &
	98	ONLY: coupling_mode, coupling_topology, gathered_size, momentum_advec, &
	99	outflow_source_plane, recycling_width, scalar_advec, subdomain_size, &
	100	turbulent_inflow, turbulent_outflow, y_shift
	101
[1320]	102	USE grid_variables, &
	103	ONLY: dx
[4444]	104	#endif
[1320]	105
	106	USE indices, &
[4444]	107	ONLY: nnx, nny, nnz, nx, nxl, nxl_mg, &
	108	nxlu, nxr, nxr_mg, ny, nyn, nyn_mg, nys, nys_mg, &
[1320]	109	nysv, nz, nzb, nzt, nzt_mg, wall_flags_1, wall_flags_2, &
	110	wall_flags_3, wall_flags_4, wall_flags_5, wall_flags_6, &
	111	wall_flags_7, wall_flags_8, wall_flags_9, wall_flags_10
[1]	112
[4444]	113	#if defined( __parallel )
	114	USE indices, &
	115	ONLY: mg_loc_ind, nbgp, nx_a, nx_o, ny_a, ny_o
	116	#endif
	117
[1320]	118	USE kinds
	119
	120	USE pegrid
[3999]	121
[4444]	122	#if defined( __parallel )
[3999]	123	USE pmc_interface, &
	124	ONLY: nested_run
[4444]	125
[1833]	126	USE spectra_mod, &
[4444]	127	ONLY: calculate_spectra
[1833]	128
[2259]	129	USE synthetic_turbulence_generator_mod, &
[2938]	130	ONLY: id_stg_left, id_stg_north, id_stg_right, id_stg_south, &
	131	use_syn_turb_gen
[4444]	132	#endif
[2259]	133
[1320]	134	USE transpose_indices, &
[4444]	135	ONLY: nxl_y, nxl_z, nxr_y, nxr_z, nyn_x, nyn_z, nys_x,&
	136	nys_z, nzb_x, nzb_y, nzt_x, nzt_y
[667]	137
[4444]	138	#if defined( __parallel )
	139	USE transpose_indices, &
	140	ONLY: nxl_yd, nxr_yd, nzb_yd, nzt_yd
	141
[2365]	142	USE vertical_nesting_mod, &
	143	ONLY: vnested, vnest_init_pegrid_domain, vnest_init_pegrid_rank
[4444]	144	#endif
[2365]	145
[1]	146	IMPLICIT NONE
	147
[3552]	148	INTEGER(iwp) :: i !< running index over number of processors or number of multigrid level
[4444]	149	#if defined( __parallel )
[3552]	150	INTEGER(iwp) :: id_inflow_l !< ID indicating processors located at the left inflow boundary
[2050]	151	INTEGER(iwp) :: id_outflow_l !< local value of id_outflow
	152	INTEGER(iwp) :: id_outflow_source_l !< local value of id_outflow_source
[3552]	153	INTEGER(iwp) :: id_recycling_l !< ID indicating processors located at the recycling plane
[2938]	154	INTEGER(iwp) :: id_stg_left_l !< left lateral boundary local core id in case of turbulence generator
	155	INTEGER(iwp) :: id_stg_north_l !< north lateral boundary local core id in case of turbulence generator
	156	INTEGER(iwp) :: id_stg_right_l !< right lateral boundary local core id in case of turbulence generator
	157	INTEGER(iwp) :: id_stg_south_l !< south lateral boundary local core id in case of turbulence generator
[3552]	158	INTEGER(iwp) :: ind(5) !< array containing the subdomain bounds
[4444]	159	#endif
[3552]	160	INTEGER(iwp) :: j !< running index, used for various loops
	161	INTEGER(iwp) :: k !< number of vertical grid points in different multigrid level
	162	INTEGER(iwp) :: maximum_grid_level_l !< maximum number of grid level without switching to PE 0
	163	INTEGER(iwp) :: mg_levels_x !< maximum number of grid level allowed along x-direction
	164	INTEGER(iwp) :: mg_levels_y !< maximum number of grid level allowed along y-direction
	165	INTEGER(iwp) :: mg_levels_z !< maximum number of grid level allowed along z-direction
	166	INTEGER(iwp) :: mg_switch_to_pe0_level_l !< maximum number of grid level with switching to PE 0
[4444]	167	#if defined( __parallel )
[3552]	168	INTEGER(iwp) :: nnx_y !< quotient of number of grid points along x-direction and number of PEs used along y-direction
	169	INTEGER(iwp) :: nny_x !< quotient of number of grid points along y-direction and number of PEs used along x-direction
	170	INTEGER(iwp) :: nny_z !< quotient of number of grid points along y-direction and number of PEs used along x-direction
	171	INTEGER(iwp) :: nnz_x !< quotient of number of grid points along z-direction and number of PEs used along x-direction
	172	INTEGER(iwp) :: nnz_y !< quotient of number of grid points along z-direction and number of PEs used along x-direction
	173	INTEGER(iwp) :: numproc_sqr !< square root of the number of processors
[4444]	174	#endif
[3552]	175	INTEGER(iwp) :: nxl_l !< lower index bound along x-direction on subdomain and different multigrid level
	176	INTEGER(iwp) :: nxr_l !< upper index bound along x-direction on subdomain and different multigrid level
	177	INTEGER(iwp) :: nyn_l !< lower index bound along y-direction on subdomain and different multigrid level
	178	INTEGER(iwp) :: nys_l !< upper index bound along y-direction on subdomain and different multigrid level
[4444]	179	#if defined( __parallel )
[3552]	180	INTEGER(iwp) :: nzb_l !< lower index bound along z-direction on subdomain and different multigrid level
[4444]	181	#endif
[3552]	182	INTEGER(iwp) :: nzt_l !< upper index bound along z-direction on subdomain and different multigrid level
	183	!$ INTEGER(iwp) :: omp_get_num_threads !< number of OpenMP threads
[1]	184
[4444]	185	#if defined( __parallel )
[3552]	186	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: ind_all !< dummy array containing index bounds on subdomain, used for gathering
	187	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nxlf !< lower index bound allong x-direction for every PE
	188	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nxrf !< upper index bound allong x-direction for every PE
	189	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nynf !< lower index bound allong y-direction for every PE
	190	INTEGER(iwp), DIMENSION(:), ALLOCATABLE :: nysf !< lower index bound allong y-direction for every PE
[1]	191
[3552]	192	INTEGER(iwp), DIMENSION(2) :: pdims_remote !< number of PEs used for coupled model (only in atmospher-ocean coupling)
[2372]	193	INTEGER(iwp) :: lcoord(2) !< PE coordinates of left neighbor along x and y
	194	INTEGER(iwp) :: rcoord(2) !< PE coordinates of right neighbor along x and y
[4444]	195	#endif
[667]	196
[1]	197	!
	198	!-- Get the number of OpenMP threads
	199	!$OMP PARALLEL
	200	!$ threads_per_task = omp_get_num_threads()
	201	!$OMP END PARALLEL
	202
	203
	204	#if defined( __parallel )
[667]	205
[3885]	206	CALL location_message( 'creating virtual PE grids + MPI derived data types', 'start' )
[1764]	207
[1]	208	!
[2177]	209	!-- Determine the processor topology or check it, if prescribed by the user
[1779]	210	IF ( npex == -1 .AND. npey == -1 ) THEN
[1]	211
	212	!
[2177]	213	!-- Automatic determination of the topology
[1779]	214	numproc_sqr = SQRT( REAL( numprocs, KIND=wp ) )
	215	pdims(1) = MAX( numproc_sqr , 1 )
[2180]	216	DO WHILE ( MOD( numprocs , pdims(1) ) /= 0 )
[1779]	217	pdims(1) = pdims(1) - 1
	218	ENDDO
[2180]	219	pdims(2) = numprocs / pdims(1)
[1]	220
[1779]	221	ELSEIF ( npex /= -1 .AND. npey /= -1 ) THEN
[1]	222
	223	!
[1779]	224	!-- Prescribed by user. Number of processors on the prescribed topology
	225	!-- must be equal to the number of PEs available to the job
	226	IF ( ( npex * npey ) /= numprocs ) THEN
[3045]	227	WRITE( message_string, * ) 'number of PEs of the prescribed ', &
[3046]	228	'topology (', npex*npey,') does not match & the number of ', &
[1779]	229	'PEs available to the job (', numprocs, ')'
	230	CALL message( 'init_pegrid', 'PA0221', 1, 2, 0, 6, 0 )
	231	ENDIF
	232	pdims(1) = npex
	233	pdims(2) = npey
[1]	234
[1779]	235	ELSE
[1]	236	!
[1779]	237	!-- If the processor topology is prescribed by the user, the number of
	238	!-- PEs must be given in both directions
[3045]	239	message_string = 'if the processor topology is prescribed by th' // &
[3046]	240	'e user & both values of "npex" and "npey" must be given' // &
[1779]	241	' in the &NAMELIST-parameter file'
	242	CALL message( 'init_pegrid', 'PA0222', 1, 2, 0, 6, 0 )
[1]	243
	244	ENDIF
	245
	246	!
[4461]	247	!-- Create four default MPI communicators for the 2d virtual PE grid. One of them will be used
	248	!-- as the main communicator for this run, while others might be used for specific quantities like
	249	!-- aerosol, chemical species, or passive scalars), if their horizontal boundary conditions shall
	250	!-- be different from those of the other quantities (e.g. non-cyclic conditions for aerosols, and
	251	!-- cyclic conditions for all others).
	252	DO i = 1, 4
	253
	254	IF ( i == 1 ) cyclic = (/ .TRUE., .TRUE. /) ! cyclic along x and y
	255	IF ( i == 2 ) cyclic = (/ .TRUE., .FALSE. /) ! cyclic along x
	256	IF ( i == 3 ) cyclic = (/ .FALSE., .TRUE. /) ! cyllic along y
	257	IF ( i == 4 ) cyclic = (/ .FALSE., .FALSE. /) ! non-cyclic
	258
	259	CALL MPI_CART_CREATE( comm_palm, ndim, pdims, cyclic, reorder, &
	260	communicator_configurations(i)%mpi_communicator, ierr )
	261
	262	CALL MPI_CART_SHIFT( communicator_configurations(i)%mpi_communicator, 0, 1, &
	263	communicator_configurations(i)%pleft, &
	264	communicator_configurations(i)%pright, ierr )
	265
	266	CALL MPI_CART_SHIFT( communicator_configurations(i)%mpi_communicator, 1, 1, &
	267	communicator_configurations(i)%psouth, &
	268	communicator_configurations(i)%pnorth, ierr )
	269
	270	ENDDO
	271
	272	!
[1]	273	!-- If necessary, set horizontal boundary conditions to non-cyclic
[722]	274	IF ( bc_lr /= 'cyclic' ) cyclic(1) = .FALSE.
	275	IF ( bc_ns /= 'cyclic' ) cyclic(2) = .FALSE.
[1]	276
[807]	277
[1]	278	!
[4461]	279	!-- Set the main communicator (virtual pe grid) for this run
	280	IF ( bc_lr == 'cyclic' .AND. bc_ns == 'cyclic' ) i = 1
	281	IF ( bc_lr == 'cyclic' .AND. bc_ns /= 'cyclic' ) i = 2
	282	IF ( bc_lr /= 'cyclic' .AND. bc_ns == 'cyclic' ) i = 3
	283	IF ( bc_lr /= 'cyclic' .AND. bc_ns /= 'cyclic' ) i = 4
	284
	285	comm2d = communicator_configurations(i)%mpi_communicator
	286	pleft = communicator_configurations(i)%pleft
	287	pright = communicator_configurations(i)%pright
	288	psouth = communicator_configurations(i)%psouth
	289	pnorth = communicator_configurations(i)%pnorth
	290
	291	!
	292	!-- Set rank and coordinates of the main communicator
[1]	293	CALL MPI_COMM_RANK( comm2d, myid, ierr )
[1468]	294	WRITE (myid_char,'(''_'',I6.6)') myid
[1]	295
	296	CALL MPI_CART_COORDS( comm2d, myid, ndim, pcoord, ierr )
[4461]	297
[1]	298	!
[2372]	299	!-- In case of cyclic boundary conditions, a y-shift at the boundaries in
	300	!-- x-direction can be introduced via parameter y_shift. The shift is done
	301	!-- by modifying the processor grid in such a way that processors located
	302	!-- at the x-boundary communicate across it to processors with y-coordinate
	303	!-- shifted by y_shift relative to their own. This feature can not be used
	304	!-- in combination with an fft pressure solver. It has been implemented to
	305	!-- counter the effect of streak structures in case of cyclic boundary
	306	!-- conditions. For a description of these see Munters
	307	!-- (2016; dx.doi.org/10.1063/1.4941912)
	308	!--
	309	!-- Get coordinates of left and right neighbor on PE grid
	310	IF ( y_shift /= 0 ) THEN
[4301]	311	IF ( bc_lr == 'cyclic' ) THEN
	312	IF ( TRIM( psolver ) /= 'multigrid' .AND. &
	313	TRIM( psolver ) /= 'multigrid_noopt') &
	314	THEN
	315	message_string = 'y_shift /= 0 requires a multigrid pressure solver '
	316	CALL message( 'check_parameters', 'PA0468', 1, 2, 0, 6, 0 )
	317	ENDIF
[2372]	318
[4301]	319	CALL MPI_CART_COORDS( comm2d, pright, ndim, rcoord, ierr )
	320	CALL MPI_CART_COORDS( comm2d, pleft, ndim, lcoord, ierr )
[2372]	321
[4301]	322	!
	323	!-- If the x(y)-coordinate of the right (left) neighbor is smaller (greater)
	324	!-- than that of the calling process, then the calling process is located on
	325	!-- the right (left) boundary of the processor grid. In that case,
	326	!-- the y-coordinate of that neighbor is increased (decreased) by y_shift.
	327	!-- The rank of the process with that coordinate is then inquired and the
	328	!-- neighbor rank for MPI_SENDRECV, pright (pleft) is set to it.
	329	!-- In this way, the calling process receives a new right (left) neighbor
	330	!-- for all future MPI_SENDRECV calls. That neighbor has a y-coordinate
	331	!-- of y+(-)y_shift, where y is the original right (left) neighbor's
	332	!-- y-coordinate. The modulo-operation ensures that if the neighbor's
	333	!-- y-coordinate exceeds the grid-boundary, it will be relocated to
	334	!-- the opposite part of the grid cyclicly.
	335	IF ( rcoord(1) < pcoord(1) ) THEN
	336	rcoord(2) = MODULO( rcoord(2) + y_shift, pdims(2) )
	337	CALL MPI_CART_RANK( comm2d, rcoord, pright, ierr )
	338	ENDIF
[2372]	339
[4301]	340	IF ( lcoord(1) > pcoord(1) ) THEN
	341	lcoord(2) = MODULO( lcoord(2) - y_shift, pdims(2) )
	342	CALL MPI_CART_RANK( comm2d, lcoord, pleft, ierr )
	343	ENDIF
	344
	345	ELSE
[2372]	346	!
[4301]	347	!-- y-shift for non-cyclic boundary conditions is only implemented
	348	!-- for the turbulence recycling method in inflow_turbulence.f90
	349	IF ( .NOT. turbulent_inflow ) THEN
	350	message_string = 'y_shift /= 0 is only allowed for cyclic ' // &
	351	'boundary conditions in both directions ' // &
	352	'or with turbulent_inflow == .TRUE.'
	353	CALL message( 'check_parameters', 'PA0467', 1, 2, 0, 6, 0 )
	354	ENDIF
[2372]	355	ENDIF
	356	ENDIF
[4461]	357
[2372]	358	!
[2365]	359	!-- Vertical nesting: store four lists that identify partner ranks to exchange
	360	!-- data
	361	IF ( vnested ) CALL vnest_init_pegrid_rank
	362
	363	!
[1]	364	!-- Determine sub-topologies for transpositions
	365	!-- Transposition from z to x:
	366	remain_dims(1) = .TRUE.
	367	remain_dims(2) = .FALSE.
	368	CALL MPI_CART_SUB( comm2d, remain_dims, comm1dx, ierr )
	369	CALL MPI_COMM_RANK( comm1dx, myidx, ierr )
	370	!
	371	!-- Transposition from x to y
	372	remain_dims(1) = .FALSE.
	373	remain_dims(2) = .TRUE.
	374	CALL MPI_CART_SUB( comm2d, remain_dims, comm1dy, ierr )
	375	CALL MPI_COMM_RANK( comm1dy, myidy, ierr )
	376
	377
	378	!
[1003]	379	!-- Calculate array bounds along x-direction for every PE.
[3045]	380	ALLOCATE( nxlf(0:pdims(1)-1), nxrf(0:pdims(1)-1), nynf(0:pdims(2)-1), &
[1003]	381	nysf(0:pdims(2)-1) )
[1]	382
[1003]	383	IF ( MOD( nx+1 , pdims(1) ) /= 0 ) THEN
[3045]	384	WRITE( message_string, * ) 'x-direction: gridpoint number (',nx+1,') ', &
[4264]	385	'is not an& integral multiple of the number',&
	386	' of processors (',pdims(1),')'
[254]	387	CALL message( 'init_pegrid', 'PA0225', 1, 2, 0, 6, 0 )
[1]	388	ELSE
[1003]	389	nnx = ( nx + 1 ) / pdims(1)
[4264]	390	ENDIF
[1]	391
	392	!
	393	!-- Left and right array bounds, number of gridpoints
	394	DO i = 0, pdims(1)-1
	395	nxlf(i) = i * nnx
	396	nxrf(i) = ( i + 1 ) * nnx - 1
	397	ENDDO
	398
	399	!
	400	!-- Calculate array bounds in y-direction for every PE.
[1003]	401	IF ( MOD( ny+1 , pdims(2) ) /= 0 ) THEN
[274]	402	WRITE( message_string, * ) 'y-direction: gridpoint number (',ny+1,') ', &
[4264]	403	'is not an& integral multiple of the number',&
	404	' of processors (',pdims(2),')'
[254]	405	CALL message( 'init_pegrid', 'PA0227', 1, 2, 0, 6, 0 )
[1]	406	ELSE
[1003]	407	nny = ( ny + 1 ) / pdims(2)
[4264]	408	ENDIF
[1]	409
	410	!
	411	!-- South and north array bounds
	412	DO j = 0, pdims(2)-1
	413	nysf(j) = j * nny
	414	nynf(j) = ( j + 1 ) * nny - 1
	415	ENDDO
	416
	417	!
	418	!-- Local array bounds of the respective PEs
[1003]	419	nxl = nxlf(pcoord(1))
	420	nxr = nxrf(pcoord(1))
	421	nys = nysf(pcoord(2))
	422	nyn = nynf(pcoord(2))
	423	nzb = 0
	424	nzt = nz
	425	nnz = nz
[1]	426
	427	!
[707]	428	!-- Set switches to define if the PE is situated at the border of the virtual
	429	!-- processor grid
	430	IF ( nxl == 0 ) left_border_pe = .TRUE.
	431	IF ( nxr == nx ) right_border_pe = .TRUE.
	432	IF ( nys == 0 ) south_border_pe = .TRUE.
	433	IF ( nyn == ny ) north_border_pe = .TRUE.
	434
	435	!
[1]	436	!-- Calculate array bounds and gridpoint numbers for the transposed arrays
	437	!-- (needed in the pressure solver)
	438	!-- For the transposed arrays, cyclic boundaries as well as top and bottom
	439	!-- boundaries are omitted, because they are obstructive to the transposition
	440
	441	!
	442	!-- 1. transposition z --> x
[1001]	443	!-- This transposition is not neccessary in case of a 1d-decomposition along x
[2938]	444	IF ( psolver == 'poisfft' .OR. calculate_spectra ) THEN
[1304]	445
[1922]	446	IF ( pdims(2) /= 1 ) THEN
	447	IF ( MOD( nz , pdims(1) ) /= 0 ) THEN
[4264]	448	WRITE( message_string, * ) 'transposition z --> x:& ', &
	449	'nz=',nz,' is not an integral multiple ',&
	450	'of pdims(1)=',pdims(1)
[1922]	451	CALL message( 'init_pegrid', 'PA0230', 1, 2, 0, 6, 0 )
	452	ENDIF
[1]	453	ENDIF
[1922]	454
	455	nys_x = nys
	456	nyn_x = nyn
	457	nny_x = nny
	458	nnz_x = nz / pdims(1)
	459	nzb_x = 1 + myidx * nnz_x
	460	nzt_x = ( myidx + 1 ) * nnz_x
	461	sendrecvcount_zx = nnx * nny * nnz_x
	462
[1]	463	ENDIF
	464
[1922]	465
[4264]	466	IF ( psolver == 'poisfft' ) THEN
[1]	467	!
[1922]	468	!-- 2. transposition x --> y
	469	IF ( MOD( nx+1 , pdims(2) ) /= 0 ) THEN
[4264]	470	WRITE( message_string, * ) 'transposition x --> y:& ', &
	471	'nx+1=',nx+1,' is not an integral ', &
	472	'multiple of pdims(2)=',pdims(2)
[1922]	473	CALL message( 'init_pegrid', 'PA0231', 1, 2, 0, 6, 0 )
	474	ENDIF
[1]	475
[1922]	476	nnz_y = nnz_x
	477	nzb_y = nzb_x
	478	nzt_y = nzt_x
	479	nnx_y = (nx+1) / pdims(2)
	480	nxl_y = myidy * nnx_y
	481	nxr_y = ( myidy + 1 ) * nnx_y - 1
	482	sendrecvcount_xy = nnx_y * nny_x * nnz_y
[1]	483	!
[4264]	484	!-- 3. transposition y --> z
[1922]	485	!-- (ELSE: x --> y in case of 1D-decomposition along x)
	486	nxl_z = nxl_y
	487	nxr_z = nxr_y
	488	nny_z = (ny+1) / pdims(1)
	489	nys_z = myidx * nny_z
	490	nyn_z = ( myidx + 1 ) * nny_z - 1
	491	sendrecvcount_yz = nnx_y * nny_z * nnz_y
[1304]	492
[1922]	493	IF ( pdims(2) /= 1 ) THEN
[1]	494	!
[1922]	495	!-- y --> z
	496	!-- This transposition is not neccessary in case of a 1d-decomposition
	497	!-- along x, except that the uptream-spline method is switched on
	498	IF ( MOD( ny+1 , pdims(1) ) /= 0 ) THEN
[4264]	499	WRITE( message_string, * ) 'transposition y --> z:& ', &
	500	'ny+1=',ny+1,' is not an integral ', &
	501	'multiple of pdims(1)=',pdims(1)
[1922]	502	CALL message( 'init_pegrid', 'PA0232', 1, 2, 0, 6, 0 )
	503	ENDIF
[1]	504
[1922]	505	ELSE
[1]	506	!
[1922]	507	!-- x --> y
	508	!-- This condition must be fulfilled for a 1D-decomposition along x
	509	IF ( MOD( ny+1 , pdims(1) ) /= 0 ) THEN
[4264]	510	WRITE( message_string, * ) 'transposition x --> y:& ', &
	511	'ny+1=',ny+1,' is not an integral ', &
	512	'multiple of pdims(1)=',pdims(1)
[1922]	513	CALL message( 'init_pegrid', 'PA0233', 1, 2, 0, 6, 0 )
	514	ENDIF
	515
[1]	516	ENDIF
	517
	518	ENDIF
	519
	520	!
	521	!-- Indices for direct transpositions z --> y (used for calculating spectra)
[1922]	522	IF ( calculate_spectra ) THEN
[1003]	523	IF ( MOD( nz, pdims(2) ) /= 0 ) THEN
[1922]	524	WRITE( message_string, * ) 'direct transposition z --> y (needed ', &
[4264]	525	'for spectra):& nz=',nz,' is not an ', &
	526	'integral multiple of pdims(2)=',pdims(2)
[254]	527	CALL message( 'init_pegrid', 'PA0234', 1, 2, 0, 6, 0 )
[1]	528	ELSE
[1003]	529	nxl_yd = nxl
	530	nxr_yd = nxr
	531	nzb_yd = 1 + myidy * ( nz / pdims(2) )
	532	nzt_yd = ( myidy + 1 ) * ( nz / pdims(2) )
	533	sendrecvcount_zyd = nnx * nny * ( nz / pdims(2) )
[1]	534	ENDIF
	535	ENDIF
	536
[1922]	537	IF ( psolver == 'poisfft' .OR. calculate_spectra ) THEN
[1]	538	!
[1922]	539	!-- Indices for direct transpositions y --> x
	540	!-- (they are only possible in case of a 1d-decomposition along x)
	541	IF ( pdims(2) == 1 ) THEN
	542	nny_x = nny / pdims(1)
	543	nys_x = myid * nny_x
	544	nyn_x = ( myid + 1 ) * nny_x - 1
	545	nzb_x = 1
	546	nzt_x = nz
	547	sendrecvcount_xy = nnx * nny_x * nz
	548	ENDIF
	549
[1]	550	ENDIF
	551
[1922]	552	IF ( psolver == 'poisfft' ) THEN
[1]	553	!
[1922]	554	!-- Indices for direct transpositions x --> y
	555	!-- (they are only possible in case of a 1d-decomposition along y)
	556	IF ( pdims(1) == 1 ) THEN
	557	nnx_y = nnx / pdims(2)
	558	nxl_y = myid * nnx_y
	559	nxr_y = ( myid + 1 ) * nnx_y - 1
	560	nzb_y = 1
	561	nzt_y = nz
	562	sendrecvcount_xy = nnx_y * nny * nz
	563	ENDIF
	564
[1]	565	ENDIF
	566
	567	!
	568	!-- Arrays for storing the array bounds are needed any more
	569	DEALLOCATE( nxlf , nxrf , nynf , nysf )
	570
[807]	571
[145]	572	!
	573	!-- Collect index bounds from other PEs (to be written to restart file later)
	574	ALLOCATE( hor_index_bounds(4,0:numprocs-1) )
	575
	576	IF ( myid == 0 ) THEN
	577
	578	hor_index_bounds(1,0) = nxl
	579	hor_index_bounds(2,0) = nxr
	580	hor_index_bounds(3,0) = nys
	581	hor_index_bounds(4,0) = nyn
	582
	583	!
	584	!-- Receive data from all other PEs
	585	DO i = 1, numprocs-1
	586	CALL MPI_RECV( ibuf, 4, MPI_INTEGER, i, MPI_ANY_TAG, comm2d, status, &
	587	ierr )
	588	hor_index_bounds(:,i) = ibuf(1:4)
	589	ENDDO
	590
	591	ELSE
	592	!
	593	!-- Send index bounds to PE0
	594	ibuf(1) = nxl
	595	ibuf(2) = nxr
	596	ibuf(3) = nys
	597	ibuf(4) = nyn
	598	CALL MPI_SEND( ibuf, 4, MPI_INTEGER, 0, myid, comm2d, ierr )
	599
	600	ENDIF
	601
[807]	602
[1]	603	#if defined( __print )
	604	!
	605	!-- Control output
	606	IF ( myid == 0 ) THEN
	607	PRINT, ' processor topology *'
	608	PRINT*, ' '
	609	PRINT*, 'myid pcoord left right south north idx idy nxl: nxr',&
	610	&' nys: nyn'
	611	PRINT*, '------------------------------------------------------------',&
	612	&'-----------'
	613	WRITE (*,1000) 0, pcoord(1), pcoord(2), pleft, pright, psouth, pnorth, &
	614	myidx, myidy, nxl, nxr, nys, nyn
	615	1000 FORMAT (I4,2X,'(',I3,',',I3,')',3X,I4,2X,I4,3X,I4,2X,I4,2X,I3,1X,I3, &
	616	2(2X,I4,':',I4))
	617
	618	!
[108]	619	!-- Receive data from the other PEs
[1]	620	DO i = 1,numprocs-1
	621	CALL MPI_RECV( ibuf, 12, MPI_INTEGER, i, MPI_ANY_TAG, comm2d, status, &
	622	ierr )
	623	WRITE (*,1000) i, ( ibuf(j) , j = 1,12 )
	624	ENDDO
	625	ELSE
	626
	627	!
	628	!-- Send data to PE0
	629	ibuf(1) = pcoord(1); ibuf(2) = pcoord(2); ibuf(3) = pleft
	630	ibuf(4) = pright; ibuf(5) = psouth; ibuf(6) = pnorth; ibuf(7) = myidx
	631	ibuf(8) = myidy; ibuf(9) = nxl; ibuf(10) = nxr; ibuf(11) = nys
	632	ibuf(12) = nyn
	633	CALL MPI_SEND( ibuf, 12, MPI_INTEGER, 0, myid, comm2d, ierr )
	634	ENDIF
	635	#endif
	636
[667]	637	!
[709]	638	!-- Determine the number of ghost point layers
[3347]	639	IF ( scalar_advec == 'ws-scheme' .OR. &
[3999]	640	momentum_advec == 'ws-scheme' .OR. nested_run ) THEN
[667]	641	nbgp = 3
	642	ELSE
	643	nbgp = 1
[709]	644	ENDIF
[667]	645
[102]	646	!
[4241]	647	!-- Check that the number of computational grid points is not smaller than the number of
	648	!-- ghost points.
	649	IF ( nnx < nbgp ) THEN
	650	WRITE( message_string, * ) 'number of subdomain grid points along x (', nnx, ') is smaller',&
	651	'than the number of ghost points (', nbgp, ')'
	652	CALL message( 'init_pegrid', 'PA0682', 1, 2, 0, 6, 0 )
	653	ENDIF
	654	IF ( nny < nbgp ) THEN
	655	WRITE( message_string, * ) 'number of subdomain grid points along y (', nny, ') is smaller',&
	656	'than the number of ghost points (', nbgp, ')'
	657	CALL message( 'init_pegrid', 'PA0683', 1, 2, 0, 6, 0 )
	658	ENDIF
	659
	660	!
[709]	661	!-- Create a new MPI derived datatype for the exchange of surface (xy) data,
	662	!-- which is needed for coupled atmosphere-ocean runs.
	663	!-- First, calculate number of grid points of an xy-plane.
[667]	664	ngp_xy = ( nxr - nxl + 1 + 2 * nbgp ) * ( nyn - nys + 1 + 2 * nbgp )
[102]	665	CALL MPI_TYPE_VECTOR( ngp_xy, 1, nzt-nzb+2, MPI_REAL, type_xy, ierr )
	666	CALL MPI_TYPE_COMMIT( type_xy, ierr )
[667]	667
[2365]	668	IF ( TRIM( coupling_mode ) /= 'uncoupled' .AND. .NOT. vnested ) THEN
[667]	669
	670	!
	671	!-- Pass the number of grid points of the atmosphere model to
	672	!-- the ocean model and vice versa
	673	IF ( coupling_mode == 'atmosphere_to_ocean' ) THEN
	674
	675	nx_a = nx
	676	ny_a = ny
	677
[709]	678	IF ( myid == 0 ) THEN
	679
	680	CALL MPI_SEND( nx_a, 1, MPI_INTEGER, numprocs, 1, comm_inter, &
	681	ierr )
	682	CALL MPI_SEND( ny_a, 1, MPI_INTEGER, numprocs, 2, comm_inter, &
	683	ierr )
	684	CALL MPI_SEND( pdims, 2, MPI_INTEGER, numprocs, 3, comm_inter, &
	685	ierr )
	686	CALL MPI_RECV( nx_o, 1, MPI_INTEGER, numprocs, 4, comm_inter, &
	687	status, ierr )
	688	CALL MPI_RECV( ny_o, 1, MPI_INTEGER, numprocs, 5, comm_inter, &
	689	status, ierr )
	690	CALL MPI_RECV( pdims_remote, 2, MPI_INTEGER, numprocs, 6, &
[667]	691	comm_inter, status, ierr )
	692	ENDIF
	693
[709]	694	CALL MPI_BCAST( nx_o, 1, MPI_INTEGER, 0, comm2d, ierr )
	695	CALL MPI_BCAST( ny_o, 1, MPI_INTEGER, 0, comm2d, ierr )
	696	CALL MPI_BCAST( pdims_remote, 2, MPI_INTEGER, 0, comm2d, ierr )
[667]	697
	698	ELSEIF ( coupling_mode == 'ocean_to_atmosphere' ) THEN
	699
	700	nx_o = nx
	701	ny_o = ny
	702
	703	IF ( myid == 0 ) THEN
[709]	704
	705	CALL MPI_RECV( nx_a, 1, MPI_INTEGER, 0, 1, comm_inter, status, &
	706	ierr )
	707	CALL MPI_RECV( ny_a, 1, MPI_INTEGER, 0, 2, comm_inter, status, &
	708	ierr )
	709	CALL MPI_RECV( pdims_remote, 2, MPI_INTEGER, 0, 3, comm_inter, &
	710	status, ierr )
	711	CALL MPI_SEND( nx_o, 1, MPI_INTEGER, 0, 4, comm_inter, ierr )
	712	CALL MPI_SEND( ny_o, 1, MPI_INTEGER, 0, 5, comm_inter, ierr )
	713	CALL MPI_SEND( pdims, 2, MPI_INTEGER, 0, 6, comm_inter, ierr )
[667]	714	ENDIF
	715
	716	CALL MPI_BCAST( nx_a, 1, MPI_INTEGER, 0, comm2d, ierr)
	717	CALL MPI_BCAST( ny_a, 1, MPI_INTEGER, 0, comm2d, ierr)
	718	CALL MPI_BCAST( pdims_remote, 2, MPI_INTEGER, 0, comm2d, ierr)
	719
	720	ENDIF
	721
[709]	722	ngp_a = ( nx_a+1 + 2 * nbgp ) * ( ny_a+1 + 2 * nbgp )
	723	ngp_o = ( nx_o+1 + 2 * nbgp ) * ( ny_o+1 + 2 * nbgp )
[667]	724
	725	!
[709]	726	!-- Determine if the horizontal grid and the number of PEs in ocean and
	727	!-- atmosphere is same or not
	728	IF ( nx_o == nx_a .AND. ny_o == ny_a .AND. &
[667]	729	pdims(1) == pdims_remote(1) .AND. pdims(2) == pdims_remote(2) ) &
	730	THEN
	731	coupling_topology = 0
	732	ELSE
	733	coupling_topology = 1
	734	ENDIF
	735
	736	!
	737	!-- Determine the target PEs for the exchange between ocean and
	738	!-- atmosphere (comm2d)
[709]	739	IF ( coupling_topology == 0 ) THEN
	740	!
	741	!-- In case of identical topologies, every atmosphere PE has exactly one
	742	!-- ocean PE counterpart and vice versa
	743	IF ( TRIM( coupling_mode ) == 'atmosphere_to_ocean' ) THEN
[667]	744	target_id = myid + numprocs
	745	ELSE
	746	target_id = myid
	747	ENDIF
	748
	749	ELSE
	750	!
	751	!-- In case of nonequivalent topology in ocean and atmosphere only for
	752	!-- PE0 in ocean and PE0 in atmosphere a target_id is needed, since
[709]	753	!-- data echxchange between ocean and atmosphere will be done only
	754	!-- between these PEs.
	755	IF ( myid == 0 ) THEN
	756
	757	IF ( TRIM( coupling_mode ) == 'atmosphere_to_ocean' ) THEN
[667]	758	target_id = numprocs
	759	ELSE
	760	target_id = 0
	761	ENDIF
[709]	762
[667]	763	ENDIF
[709]	764
[667]	765	ENDIF
	766
	767	ENDIF
	768
[2365]	769	!
	770	!-- Store partner grid point co-ordinates as lists.
	771	!-- Create custom MPI vector datatypes for contiguous data transfer
	772	IF ( vnested ) CALL vnest_init_pegrid_domain
[667]	773
[1]	774	#else
	775
	776	!
	777	!-- Array bounds when running on a single PE (respectively a non-parallel
	778	!-- machine)
[1003]	779	nxl = 0
	780	nxr = nx
	781	nnx = nxr - nxl + 1
	782	nys = 0
	783	nyn = ny
	784	nny = nyn - nys + 1
	785	nzb = 0
	786	nzt = nz
	787	nnz = nz
[1]	788
[145]	789	ALLOCATE( hor_index_bounds(4,0:0) )
	790	hor_index_bounds(1,0) = nxl
	791	hor_index_bounds(2,0) = nxr
	792	hor_index_bounds(3,0) = nys
	793	hor_index_bounds(4,0) = nyn
	794
[1]	795	!
	796	!-- Array bounds for the pressure solver (in the parallel code, these bounds
	797	!-- are the ones for the transposed arrays)
[1003]	798	nys_x = nys
	799	nyn_x = nyn
	800	nzb_x = nzb + 1
	801	nzt_x = nzt
[1]	802
[1003]	803	nxl_y = nxl
	804	nxr_y = nxr
	805	nzb_y = nzb + 1
	806	nzt_y = nzt
[1]	807
[1003]	808	nxl_z = nxl
	809	nxr_z = nxr
	810	nys_z = nys
	811	nyn_z = nyn
[1]	812
	813	#endif
	814
	815	!
	816	!-- Calculate number of grid levels necessary for the multigrid poisson solver
	817	!-- as well as the gridpoint indices on each level
[1575]	818	IF ( psolver(1:9) == 'multigrid' ) THEN
[1]	819
	820	!
	821	!-- First calculate number of possible grid levels for the subdomains
	822	mg_levels_x = 1
	823	mg_levels_y = 1
	824	mg_levels_z = 1
	825
	826	i = nnx
	827	DO WHILE ( MOD( i, 2 ) == 0 .AND. i /= 2 )
	828	i = i / 2
	829	mg_levels_x = mg_levels_x + 1
	830	ENDDO
	831
	832	j = nny
	833	DO WHILE ( MOD( j, 2 ) == 0 .AND. j /= 2 )
	834	j = j / 2
	835	mg_levels_y = mg_levels_y + 1
	836	ENDDO
	837
[181]	838	k = nz ! do not use nnz because it might be > nz due to transposition
	839	! requirements
[1]	840	DO WHILE ( MOD( k, 2 ) == 0 .AND. k /= 2 )
	841	k = k / 2
	842	mg_levels_z = mg_levels_z + 1
	843	ENDDO
[2197]	844	!
	845	!-- The optimized MG-solver does not allow odd values for nz at the coarsest
	846	!-- grid level
	847	IF ( TRIM( psolver ) /= 'multigrid_noopt' ) THEN
	848	IF ( MOD( k, 2 ) /= 0 ) mg_levels_z = mg_levels_z - 1
[3057]	849	!
	850	!-- An odd value of nz does not work. The finest level must have an even
	851	!-- value.
	852	IF ( mg_levels_z == 0 ) THEN
	853	message_string = 'optimized multigrid method requires nz to be even'
[3058]	854	CALL message( 'init_pegrid', 'PA0495', 1, 2, 0, 6, 0 )
[3057]	855	ENDIF
[2197]	856	ENDIF
[1]	857
	858	maximum_grid_level = MIN( mg_levels_x, mg_levels_y, mg_levels_z )
[3890]	859	!
	860	!-- Check if subdomain sizes prevents any coarsening.
	861	!-- This case, the maximum number of grid levels is 1, i.e. effectively
	862	!-- a Gauss-Seidel scheme is applied rather than a multigrid approach.
[3897]	863	!-- Give a warning in this case.
	864	IF ( maximum_grid_level == 1 .AND. mg_switch_to_pe0_level == -1 ) THEN
	865	message_string = 'No grid coarsening possible, multigrid ' // &
	866	'approach effectively reduces to a Gauss-Seidel ' //&
	867	'scheme.'
	868
	869	CALL message( 'poismg', 'PA0648', 0, 1, 0, 6, 0 )
[3890]	870	ENDIF
[1]	871
	872	!
	873	!-- Find out, if the total domain allows more levels. These additional
[709]	874	!-- levels are identically processed on all PEs.
[197]	875	IF ( numprocs > 1 .AND. mg_switch_to_pe0_level /= -1 ) THEN
[709]	876
[1]	877	IF ( mg_levels_z > MIN( mg_levels_x, mg_levels_y ) ) THEN
[709]	878
[1]	879	mg_switch_to_pe0_level_l = maximum_grid_level
	880
	881	mg_levels_x = 1
	882	mg_levels_y = 1
	883
	884	i = nx+1
	885	DO WHILE ( MOD( i, 2 ) == 0 .AND. i /= 2 )
	886	i = i / 2
	887	mg_levels_x = mg_levels_x + 1
	888	ENDDO
	889
	890	j = ny+1
	891	DO WHILE ( MOD( j, 2 ) == 0 .AND. j /= 2 )
	892	j = j / 2
	893	mg_levels_y = mg_levels_y + 1
	894	ENDDO
	895
	896	maximum_grid_level_l = MIN( mg_levels_x, mg_levels_y, mg_levels_z )
	897
	898	IF ( maximum_grid_level_l > mg_switch_to_pe0_level_l ) THEN
	899	mg_switch_to_pe0_level_l = maximum_grid_level_l - &
	900	mg_switch_to_pe0_level_l + 1
	901	ELSE
	902	mg_switch_to_pe0_level_l = 0
	903	ENDIF
[709]	904
[1]	905	ELSE
[3057]	906
[1]	907	mg_switch_to_pe0_level_l = 0
	908	maximum_grid_level_l = maximum_grid_level
[709]	909
[1]	910	ENDIF
	911
	912	!
	913	!-- Use switch level calculated above only if it is not pre-defined
	914	!-- by user
	915	IF ( mg_switch_to_pe0_level == 0 ) THEN
	916	IF ( mg_switch_to_pe0_level_l /= 0 ) THEN
	917	mg_switch_to_pe0_level = mg_switch_to_pe0_level_l
	918	maximum_grid_level = maximum_grid_level_l
	919	ENDIF
	920
	921	ELSE
	922	!
	923	!-- Check pre-defined value and reset to default, if neccessary
[3045]	924	IF ( mg_switch_to_pe0_level < mg_switch_to_pe0_level_l .OR. &
[1]	925	mg_switch_to_pe0_level >= maximum_grid_level_l ) THEN
[3045]	926	message_string = 'mg_switch_to_pe0_level ' // &
[2271]	927	'out of range and reset to 0'
[254]	928	CALL message( 'init_pegrid', 'PA0235', 0, 1, 0, 6, 0 )
[1]	929	mg_switch_to_pe0_level = 0
	930	ELSE
	931	!
	932	!-- Use the largest number of possible levels anyway and recalculate
	933	!-- the switch level to this largest number of possible values
	934	maximum_grid_level = maximum_grid_level_l
	935
	936	ENDIF
[709]	937
[1]	938	ENDIF
	939
	940	ENDIF
	941
[1056]	942	ALLOCATE( grid_level_count(maximum_grid_level), &
	943	nxl_mg(0:maximum_grid_level), nxr_mg(0:maximum_grid_level), &
	944	nyn_mg(0:maximum_grid_level), nys_mg(0:maximum_grid_level), &
	945	nzt_mg(0:maximum_grid_level) )
[1]	946
	947	grid_level_count = 0
[1056]	948	!
	949	!-- Index zero required as dummy due to definition of arrays f2 and p2 in
	950	!-- recursive subroutine next_mg_level
	951	nxl_mg(0) = 0; nxr_mg(0) = 0; nyn_mg(0) = 0; nys_mg(0) = 0; nzt_mg(0) = 0
[778]	952
[1]	953	nxl_l = nxl; nxr_l = nxr; nys_l = nys; nyn_l = nyn; nzt_l = nzt
	954
	955	DO i = maximum_grid_level, 1 , -1
	956
	957	IF ( i == mg_switch_to_pe0_level ) THEN
[1804]	958	#if defined( __parallel )
[1]	959	!
	960	!-- Save the grid size of the subdomain at the switch level, because
	961	!-- it is needed in poismg.
	962	ind(1) = nxl_l; ind(2) = nxr_l
	963	ind(3) = nys_l; ind(4) = nyn_l
	964	ind(5) = nzt_l
	965	ALLOCATE( ind_all(5*numprocs), mg_loc_ind(5,0:numprocs-1) )
	966	CALL MPI_ALLGATHER( ind, 5, MPI_INTEGER, ind_all, 5, &
	967	MPI_INTEGER, comm2d, ierr )
	968	DO j = 0, numprocs-1
	969	DO k = 1, 5
	970	mg_loc_ind(k,j) = ind_all(k+j*5)
	971	ENDDO
	972	ENDDO
	973	DEALLOCATE( ind_all )
	974	!
[709]	975	!-- Calculate the grid size of the total domain
[1]	976	nxr_l = ( nxr_l-nxl_l+1 ) * pdims(1) - 1
	977	nxl_l = 0
	978	nyn_l = ( nyn_l-nys_l+1 ) * pdims(2) - 1
	979	nys_l = 0
	980	!
	981	!-- The size of this gathered array must not be larger than the
	982	!-- array tend, which is used in the multigrid scheme as a temporary
[778]	983	!-- array. Therefore the subdomain size of an PE is calculated and
	984	!-- the size of the gathered grid. These values are used in
	985	!-- routines pres and poismg
	986	subdomain_size = ( nxr - nxl + 2 * nbgp + 1 ) * &
	987	( nyn - nys + 2 * nbgp + 1 ) * ( nzt - nzb + 2 )
[3045]	988	gathered_size = ( nxr_l - nxl_l + 3 ) * ( nyn_l - nys_l + 3 ) * &
[1]	989	( nzt_l - nzb + 2 )
	990
[1804]	991	#else
[3045]	992	message_string = 'multigrid gather/scatter impossible ' // &
[1]	993	'in non parallel mode'
[254]	994	CALL message( 'init_pegrid', 'PA0237', 1, 2, 0, 6, 0 )
[1]	995	#endif
	996	ENDIF
	997
	998	nxl_mg(i) = nxl_l
	999	nxr_mg(i) = nxr_l
	1000	nys_mg(i) = nys_l
	1001	nyn_mg(i) = nyn_l
	1002	nzt_mg(i) = nzt_l
	1003
	1004	nxl_l = nxl_l / 2
	1005	nxr_l = nxr_l / 2
	1006	nys_l = nys_l / 2
	1007	nyn_l = nyn_l / 2
	1008	nzt_l = nzt_l / 2
[3890]	1009
[1]	1010	ENDDO
	1011
[780]	1012	!
[3045]	1013	!-- Temporary problem: Currently calculation of maxerror in routine poismg crashes
[780]	1014	!-- if grid data are collected on PE0 already on the finest grid level.
	1015	!-- To be solved later.
	1016	IF ( maximum_grid_level == mg_switch_to_pe0_level ) THEN
	1017	message_string = 'grid coarsening on subdomain level cannot be performed'
	1018	CALL message( 'poismg', 'PA0236', 1, 2, 0, 6, 0 )
	1019	ENDIF
	1020
[1]	1021	ELSE
	1022
[667]	1023	maximum_grid_level = 0
[1]	1024
	1025	ENDIF
	1026
[722]	1027	!
	1028	!-- Default level 0 tells exchange_horiz that all ghost planes have to be
	1029	!-- exchanged. grid_level is adjusted in poismg, where only one ghost plane
	1030	!-- is required.
	1031	grid_level = 0
[1]	1032
[1804]	1033	#if defined( __parallel )
[1]	1034	!
	1035	!-- Gridpoint number for the exchange of ghost points (y-line for 2D-arrays)
[667]	1036	ngp_y = nyn - nys + 1 + 2 * nbgp
[1]	1037
	1038	!
[709]	1039	!-- Define new MPI derived datatypes for the exchange of ghost points in
	1040	!-- x- and y-direction for 2D-arrays (line)
[1968]	1041	CALL MPI_TYPE_VECTOR( nxr-nxl+1+2*nbgp, nbgp, ngp_y, MPI_REAL, type_x, &
[709]	1042	ierr )
[1]	1043	CALL MPI_TYPE_COMMIT( type_x, ierr )
	1044
[667]	1045	CALL MPI_TYPE_VECTOR( nbgp, ngp_y, ngp_y, MPI_REAL, type_y, ierr )
	1046	CALL MPI_TYPE_COMMIT( type_y, ierr )
[1968]	1047	!
	1048	!-- Define new MPI derived datatypes for the exchange of ghost points in
[3542]	1049	!-- x- and y-direction for 2D-INTEGER arrays (line) - on normal grid.
	1050	!-- Define types for 32-bit and 8-bit Integer. The 8-bit Integer are only
	1051	!-- required on normal grid, while 32-bit Integer may be also required on
	1052	!-- coarser grid level in case of multigrid solver.
	1053	!
	1054	!-- 8-bit Integer
	1055	CALL MPI_TYPE_VECTOR( nxr-nxl+1+2*nbgp, nbgp, ngp_y, MPI_BYTE, &
	1056	type_x_byte, ierr )
	1057	CALL MPI_TYPE_COMMIT( type_x_byte, ierr )
	1058
	1059	CALL MPI_TYPE_VECTOR( nbgp, ngp_y, ngp_y, MPI_BYTE, &
	1060	type_y_byte, ierr )
	1061	CALL MPI_TYPE_COMMIT( type_y_byte, ierr )
	1062	!
	1063	!-- 32-bit Integer
[1968]	1064	ALLOCATE( type_x_int(0:maximum_grid_level), &
	1065	type_y_int(0:maximum_grid_level) )
[3542]	1066
[1968]	1067	CALL MPI_TYPE_VECTOR( nxr-nxl+1+2*nbgp, nbgp, ngp_y, MPI_INTEGER, &
	1068	type_x_int(0), ierr )
	1069	CALL MPI_TYPE_COMMIT( type_x_int(0), ierr )
[667]	1070
[1968]	1071	CALL MPI_TYPE_VECTOR( nbgp, ngp_y, ngp_y, MPI_INTEGER, type_y_int(0), ierr )
	1072	CALL MPI_TYPE_COMMIT( type_y_int(0), ierr )
[1]	1073	!
	1074	!-- Calculate gridpoint numbers for the exchange of ghost points along x
	1075	!-- (yz-plane for 3D-arrays) and define MPI derived data type(s) for the
	1076	!-- exchange of ghost points in y-direction (xz-plane).
	1077	!-- Do these calculations for the model grid and (if necessary) also
	1078	!-- for the coarser grid levels used in the multigrid method
[2696]	1079	ALLOCATE ( ngp_xz(0:maximum_grid_level), &
	1080	ngp_xz_int(0:maximum_grid_level), &
	1081	ngp_yz(0:maximum_grid_level), &
	1082	ngp_yz_int(0:maximum_grid_level), &
	1083	type_xz(0:maximum_grid_level), &
	1084	type_xz_int(0:maximum_grid_level), &
	1085	type_yz(0:maximum_grid_level), &
	1086	type_yz_int(0:maximum_grid_level) )
[1]	1087
	1088	nxl_l = nxl; nxr_l = nxr; nys_l = nys; nyn_l = nyn; nzb_l = nzb; nzt_l = nzt
[709]	1089
[667]	1090	!
	1091	!-- Discern between the model grid, which needs nbgp ghost points and
	1092	!-- grid levels for the multigrid scheme. In the latter case only one
	1093	!-- ghost point is necessary.
[709]	1094	!-- First definition of MPI-datatypes for exchange of ghost layers on normal
[667]	1095	!-- grid. The following loop is needed for data exchange in poismg.f90.
	1096	!
	1097	!-- Determine number of grid points of yz-layer for exchange
	1098	ngp_yz(0) = (nzt - nzb + 2) * (nyn - nys + 1 + 2 * nbgp)
[709]	1099
[667]	1100	!
[709]	1101	!-- Define an MPI-datatype for the exchange of left/right boundaries.
	1102	!-- Although data are contiguous in physical memory (which does not
	1103	!-- necessarily require an MPI-derived datatype), the data exchange between
	1104	!-- left and right PE's using the MPI-derived type is 10% faster than without.
[667]	1105	CALL MPI_TYPE_VECTOR( nxr-nxl+1+2nbgp, nbgp(nzt-nzb+2), ngp_yz(0), &
[709]	1106	MPI_REAL, type_xz(0), ierr )
[667]	1107	CALL MPI_TYPE_COMMIT( type_xz(0), ierr )
[1]	1108
[709]	1109	CALL MPI_TYPE_VECTOR( nbgp, ngp_yz(0), ngp_yz(0), MPI_REAL, type_yz(0), &
	1110	ierr )
[667]	1111	CALL MPI_TYPE_COMMIT( type_yz(0), ierr )
[709]	1112
[667]	1113	!
[2696]	1114	!-- Define data types for exchange of 3D Integer arrays.
	1115	ngp_yz_int(0) = (nzt - nzb + 2) * (nyn - nys + 1 + 2 * nbgp)
	1116
	1117	CALL MPI_TYPE_VECTOR( nxr-nxl+1+2nbgp, nbgp(nzt-nzb+2), ngp_yz_int(0), &
	1118	MPI_INTEGER, type_xz_int(0), ierr )
	1119	CALL MPI_TYPE_COMMIT( type_xz_int(0), ierr )
	1120
	1121	CALL MPI_TYPE_VECTOR( nbgp, ngp_yz_int(0), ngp_yz_int(0), MPI_INTEGER, &
	1122	type_yz_int(0), ierr )
	1123	CALL MPI_TYPE_COMMIT( type_yz_int(0), ierr )
	1124
	1125	!
[709]	1126	!-- Definition of MPI-datatypes for multigrid method (coarser level grids)
[1575]	1127	IF ( psolver(1:9) == 'multigrid' ) THEN
[667]	1128	!
[709]	1129	!-- Definition of MPI-datatyoe as above, but only 1 ghost level is used
	1130	DO i = maximum_grid_level, 1 , -1
[1968]	1131	!
[2696]	1132	!-- For 3D-exchange on different multigrid level, one ghost point for
	1133	!-- REAL arrays, two ghost points for INTEGER arrays
[1575]	1134	ngp_xz(i) = (nzt_l - nzb_l + 2) * (nxr_l - nxl_l + 3)
[667]	1135	ngp_yz(i) = (nzt_l - nzb_l + 2) * (nyn_l - nys_l + 3)
	1136
[2696]	1137	ngp_xz_int(i) = (nzt_l - nzb_l + 2) * (nxr_l - nxl_l + 3)
	1138	ngp_yz_int(i) = (nzt_l - nzb_l + 2) * (nyn_l - nys_l + 3)
	1139	!
	1140	!-- MPI data type for REAL arrays, for xz-layers
	1141	CALL MPI_TYPE_VECTOR( nxr_l-nxl_l+3, nzt_l-nzb_l+2, ngp_yz(i), &
[709]	1142	MPI_REAL, type_xz(i), ierr )
[667]	1143	CALL MPI_TYPE_COMMIT( type_xz(i), ierr )
[1]	1144
[2696]	1145	!
	1146	!-- MPI data type for INTEGER arrays, for xz-layers
	1147	CALL MPI_TYPE_VECTOR( nxr_l-nxl_l+3, nzt_l-nzb_l+2, ngp_yz_int(i), &
	1148	MPI_INTEGER, type_xz_int(i), ierr )
	1149	CALL MPI_TYPE_COMMIT( type_xz_int(i), ierr )
	1150
	1151	!
	1152	!-- MPI data type for REAL arrays, for yz-layers
[709]	1153	CALL MPI_TYPE_VECTOR( 1, ngp_yz(i), ngp_yz(i), MPI_REAL, type_yz(i), &
	1154	ierr )
[667]	1155	CALL MPI_TYPE_COMMIT( type_yz(i), ierr )
[2696]	1156	!
	1157	!-- MPI data type for INTEGER arrays, for yz-layers
	1158	CALL MPI_TYPE_VECTOR( 1, ngp_yz_int(i), ngp_yz_int(i), MPI_INTEGER, &
	1159	type_yz_int(i), ierr )
	1160	CALL MPI_TYPE_COMMIT( type_yz_int(i), ierr )
[667]	1161
[1968]	1162
	1163	!-- For 2D-exchange of INTEGER arrays on coarser grid level, where 2 ghost
[3542]	1164	!-- points need to be exchanged. Only required for 32-bit Integer arrays.
	1165	CALL MPI_TYPE_VECTOR( nxr_l-nxl_l+5, 2, nyn_l-nys_l+5, MPI_INTEGER, &
[1968]	1166	type_x_int(i), ierr )
	1167	CALL MPI_TYPE_COMMIT( type_x_int(i), ierr )
	1168
	1169
[3542]	1170	CALL MPI_TYPE_VECTOR( 2, nyn_l-nys_l+5, nyn_l-nys_l+5, MPI_INTEGER, &
[1968]	1171	type_y_int(i), ierr )
	1172	CALL MPI_TYPE_COMMIT( type_y_int(i), ierr )
	1173
[667]	1174	nxl_l = nxl_l / 2
	1175	nxr_l = nxr_l / 2
	1176	nys_l = nys_l / 2
	1177	nyn_l = nyn_l / 2
	1178	nzt_l = nzt_l / 2
[709]	1179
[667]	1180	ENDDO
[709]	1181
	1182	ENDIF
[1677]	1183
[1]	1184	#endif
	1185
[1804]	1186	#if defined( __parallel )
[1]	1187	!
[1933]	1188	!-- Setting of flags for inflow/outflow/nesting conditions.
[1964]	1189	IF ( pleft == MPI_PROC_NULL ) THEN
[3182]	1190	IF ( bc_lr == 'dirichlet/radiation' .OR. bc_lr == 'nested' .OR. &
	1191	bc_lr == 'nesting_offline' ) THEN
	1192	bc_dirichlet_l = .TRUE.
[1964]	1193	ELSEIF ( bc_lr == 'radiation/dirichlet' ) THEN
[3182]	1194	bc_radiation_l = .TRUE.
[1]	1195	ENDIF
	1196	ENDIF
[1933]	1197
[1964]	1198	IF ( pright == MPI_PROC_NULL ) THEN
	1199	IF ( bc_lr == 'dirichlet/radiation' ) THEN
[3182]	1200	bc_radiation_r = .TRUE.
	1201	ELSEIF ( bc_lr == 'radiation/dirichlet' .OR. bc_lr == 'nested' .OR. &
	1202	bc_lr == 'nesting_offline' ) THEN
	1203	bc_dirichlet_r = .TRUE.
[1]	1204	ENDIF
	1205	ENDIF
	1206
[1964]	1207	IF ( psouth == MPI_PROC_NULL ) THEN
	1208	IF ( bc_ns == 'dirichlet/radiation' ) THEN
[3182]	1209	bc_radiation_s = .TRUE.
	1210	ELSEIF ( bc_ns == 'radiation/dirichlet' .OR. bc_ns == 'nested' .OR. &
	1211	bc_ns == 'nesting_offline' ) THEN
	1212	bc_dirichlet_s = .TRUE.
[1]	1213	ENDIF
	1214	ENDIF
	1215
[1964]	1216	IF ( pnorth == MPI_PROC_NULL ) THEN
[3182]	1217	IF ( bc_ns == 'dirichlet/radiation' .OR. bc_ns == 'nested' .OR. &
	1218	bc_ns == 'nesting_offline' ) THEN
	1219	bc_dirichlet_n = .TRUE.
[1964]	1220	ELSEIF ( bc_ns == 'radiation/dirichlet' ) THEN
[3182]	1221	bc_radiation_n = .TRUE.
[1]	1222	ENDIF
	1223	ENDIF
[2938]	1224	!
	1225	!-- In case of synthetic turbulence geneartor determine ids.
	1226	!-- Please note, if no forcing or nesting is applied, the generator is applied
	1227	!-- only at the left lateral boundary.
	1228	IF ( use_syn_turb_gen ) THEN
[3182]	1229	IF ( bc_dirichlet_l ) THEN
[2938]	1230	id_stg_left_l = myidx
	1231	ELSE
	1232	id_stg_left_l = 0
	1233	ENDIF
[3182]	1234	IF ( bc_dirichlet_r ) THEN
[2938]	1235	id_stg_right_l = myidx
	1236	ELSE
	1237	id_stg_right_l = 0
	1238	ENDIF
[3182]	1239	IF ( bc_dirichlet_s ) THEN
[2938]	1240	id_stg_south_l = myidy
	1241	ELSE
	1242	id_stg_south_l = 0
	1243	ENDIF
[3182]	1244	IF ( bc_dirichlet_n ) THEN
[2938]	1245	id_stg_north_l = myidy
	1246	ELSE
	1247	id_stg_north_l = 0
	1248	ENDIF
[1968]	1249
[2938]	1250	IF ( collective_wait ) CALL MPI_BARRIER( comm2d, ierr )
	1251	CALL MPI_ALLREDUCE( id_stg_left_l, id_stg_left, 1, MPI_INTEGER, &
	1252	MPI_SUM, comm1dx, ierr )
	1253
	1254	IF ( collective_wait ) CALL MPI_BARRIER( comm2d, ierr )
	1255	CALL MPI_ALLREDUCE( id_stg_right_l, id_stg_right, 1, MPI_INTEGER, &
	1256	MPI_SUM, comm1dx, ierr )
	1257
	1258	IF ( collective_wait ) CALL MPI_BARRIER( comm2d, ierr )
	1259	CALL MPI_ALLREDUCE( id_stg_south_l, id_stg_south, 1, MPI_INTEGER, &
	1260	MPI_SUM, comm1dy, ierr )
	1261
	1262	IF ( collective_wait ) CALL MPI_BARRIER( comm2d, ierr )
	1263	CALL MPI_ALLREDUCE( id_stg_north_l, id_stg_north, 1, MPI_INTEGER, &
	1264	MPI_SUM, comm1dy, ierr )
	1265
	1266	ENDIF
	1267
[151]	1268	!
	1269	!-- Broadcast the id of the inflow PE
[3182]	1270	IF ( bc_dirichlet_l ) THEN
[163]	1271	id_inflow_l = myidx
[151]	1272	ELSE
	1273	id_inflow_l = 0
	1274	ENDIF
[622]	1275	IF ( collective_wait ) CALL MPI_BARRIER( comm2d, ierr )
[151]	1276	CALL MPI_ALLREDUCE( id_inflow_l, id_inflow, 1, MPI_INTEGER, MPI_SUM, &
	1277	comm1dx, ierr )
	1278
[163]	1279	!
	1280	!-- Broadcast the id of the recycling plane
	1281	!-- WARNING: needs to be adjusted in case of inflows other than from left side!
[3884]	1282	IF ( turbulent_inflow ) THEN
	1283
[4045]	1284	IF ( NINT( recycling_width / dx, KIND=idp ) >= nxl .AND. &
	1285	NINT( recycling_width / dx, KIND=idp ) <= nxr ) THEN
[3884]	1286	id_recycling_l = myidx
	1287	ELSE
	1288	id_recycling_l = 0
	1289	ENDIF
	1290	IF ( collective_wait ) CALL MPI_BARRIER( comm2d, ierr )
	1291	CALL MPI_ALLREDUCE( id_recycling_l, id_recycling, 1, MPI_INTEGER, MPI_SUM, &
	1292	comm1dx, ierr )
	1293
[163]	1294	ENDIF
	1295
[2050]	1296	!
	1297	!-- Broadcast the id of the outflow PE and outflow-source plane
	1298	IF ( turbulent_outflow ) THEN
	1299
[3182]	1300	IF ( bc_radiation_r ) THEN
[2050]	1301	id_outflow_l = myidx
	1302	ELSE
	1303	id_outflow_l = 0
	1304	ENDIF
	1305	IF ( collective_wait ) CALL MPI_BARRIER( comm2d, ierr )
	1306	CALL MPI_ALLREDUCE( id_outflow_l, id_outflow, 1, MPI_INTEGER, MPI_SUM, &
	1307	comm1dx, ierr )
	1308
	1309	IF ( NINT( outflow_source_plane / dx ) >= nxl .AND. &
	1310	NINT( outflow_source_plane / dx ) <= nxr ) THEN
	1311	id_outflow_source_l = myidx
	1312	ELSE
	1313	id_outflow_source_l = 0
	1314	ENDIF
	1315	IF ( collective_wait ) CALL MPI_BARRIER( comm2d, ierr )
	1316	CALL MPI_ALLREDUCE( id_outflow_source_l, id_outflow_source, 1, &
	1317	MPI_INTEGER, MPI_SUM, comm1dx, ierr )
	1318
	1319	ENDIF
	1320
[3885]	1321	CALL location_message( 'creating virtual PE grids + MPI derived data types', 'finished' )
[1384]	1322
[1804]	1323	#else
[1159]	1324	IF ( bc_lr == 'dirichlet/radiation' ) THEN
[3182]	1325	bc_dirichlet_l = .TRUE.
	1326	bc_radiation_r = .TRUE.
[1159]	1327	ELSEIF ( bc_lr == 'radiation/dirichlet' ) THEN
[3182]	1328	bc_radiation_l = .TRUE.
	1329	bc_dirichlet_r = .TRUE.
[1]	1330	ENDIF
	1331
[1159]	1332	IF ( bc_ns == 'dirichlet/radiation' ) THEN
[3182]	1333	bc_dirichlet_n = .TRUE.
	1334	bc_radiation_s = .TRUE.
[1159]	1335	ELSEIF ( bc_ns == 'radiation/dirichlet' ) THEN
[3182]	1336	bc_radiation_n = .TRUE.
	1337	bc_dirichlet_s = .TRUE.
[1]	1338	ENDIF
	1339	#endif
[807]	1340
[106]	1341	!
[978]	1342	!-- At the inflow or outflow, u or v, respectively, have to be calculated for
	1343	!-- one more grid point.
[3182]	1344	IF ( bc_dirichlet_l .OR. bc_radiation_l ) THEN
[106]	1345	nxlu = nxl + 1
	1346	ELSE
	1347	nxlu = nxl
	1348	ENDIF
[3182]	1349	IF ( bc_dirichlet_s .OR. bc_radiation_s ) THEN
[106]	1350	nysv = nys + 1
	1351	ELSE
	1352	nysv = nys
	1353	ENDIF
[1]	1354
[114]	1355	!
	1356	!-- Allocate wall flag arrays used in the multigrid solver
[1575]	1357	IF ( psolver(1:9) == 'multigrid' ) THEN
[114]	1358
	1359	DO i = maximum_grid_level, 1, -1
	1360
	1361	SELECT CASE ( i )
	1362
	1363	CASE ( 1 )
	1364	ALLOCATE( wall_flags_1(nzb:nzt_mg(i)+1, &
	1365	nys_mg(i)-1:nyn_mg(i)+1, &
	1366	nxl_mg(i)-1:nxr_mg(i)+1) )
	1367
	1368	CASE ( 2 )
	1369	ALLOCATE( wall_flags_2(nzb:nzt_mg(i)+1, &
	1370	nys_mg(i)-1:nyn_mg(i)+1, &
	1371	nxl_mg(i)-1:nxr_mg(i)+1) )
	1372
	1373	CASE ( 3 )
	1374	ALLOCATE( wall_flags_3(nzb:nzt_mg(i)+1, &
	1375	nys_mg(i)-1:nyn_mg(i)+1, &
	1376	nxl_mg(i)-1:nxr_mg(i)+1) )
	1377
	1378	CASE ( 4 )
	1379	ALLOCATE( wall_flags_4(nzb:nzt_mg(i)+1, &
	1380	nys_mg(i)-1:nyn_mg(i)+1, &
	1381	nxl_mg(i)-1:nxr_mg(i)+1) )
	1382
	1383	CASE ( 5 )
	1384	ALLOCATE( wall_flags_5(nzb:nzt_mg(i)+1, &
	1385	nys_mg(i)-1:nyn_mg(i)+1, &
	1386	nxl_mg(i)-1:nxr_mg(i)+1) )
	1387
	1388	CASE ( 6 )
	1389	ALLOCATE( wall_flags_6(nzb:nzt_mg(i)+1, &
	1390	nys_mg(i)-1:nyn_mg(i)+1, &
	1391	nxl_mg(i)-1:nxr_mg(i)+1) )
	1392
	1393	CASE ( 7 )
	1394	ALLOCATE( wall_flags_7(nzb:nzt_mg(i)+1, &
	1395	nys_mg(i)-1:nyn_mg(i)+1, &
	1396	nxl_mg(i)-1:nxr_mg(i)+1) )
	1397
	1398	CASE ( 8 )
	1399	ALLOCATE( wall_flags_8(nzb:nzt_mg(i)+1, &
	1400	nys_mg(i)-1:nyn_mg(i)+1, &
	1401	nxl_mg(i)-1:nxr_mg(i)+1) )
	1402
	1403	CASE ( 9 )
	1404	ALLOCATE( wall_flags_9(nzb:nzt_mg(i)+1, &
	1405	nys_mg(i)-1:nyn_mg(i)+1, &
	1406	nxl_mg(i)-1:nxr_mg(i)+1) )
	1407
	1408	CASE ( 10 )
	1409	ALLOCATE( wall_flags_10(nzb:nzt_mg(i)+1, &
	1410	nys_mg(i)-1:nyn_mg(i)+1, &
	1411	nxl_mg(i)-1:nxr_mg(i)+1) )
	1412
	1413	CASE DEFAULT
[254]	1414	message_string = 'more than 10 multigrid levels'
	1415	CALL message( 'init_pegrid', 'PA0238', 1, 2, 0, 6, 0 )
[114]	1416
	1417	END SELECT
	1418
	1419	ENDDO
	1420
	1421	ENDIF
	1422
[1]	1423	END SUBROUTINE init_pegrid

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