| 1 | !--------------------------------------------------------------------------------------------------! |
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| 2 | ! This file is part of the PALM model system. |
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| 3 | ! |
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| 4 | ! PALM is free software: you can redistribute it and/or modify it under the terms of the GNU General |
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| 5 | ! Public License as published by the Free Software Foundation, either version 3 of the License, or |
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| 6 | ! (at your option) any later version. |
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| 7 | ! |
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| 8 | ! PALM is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the |
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| 9 | ! implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General |
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| 10 | ! Public License for more details. |
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| 11 | ! |
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| 12 | ! You should have received a copy of the GNU General Public License along with PALM. If not, see |
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| 13 | ! <http://www.gnu.org/licenses/>. |
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| 14 | ! |
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| 15 | ! Copyright 1997-2020 Leibniz Universitaet Hannover |
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| 16 | !--------------------------------------------------------------------------------------------------! |
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| 17 | ! |
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| 18 | ! Current revisions: |
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| 19 | ! ------------------ |
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| 20 | ! |
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| 21 | ! |
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| 22 | ! Former revisions: |
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| 23 | ! ----------------- |
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| 24 | ! $Id: global_min_max.f90 4646 2020-08-24 16:02:40Z suehring $ |
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| 25 | ! file re-formatted to follow the PALM coding standard |
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| 26 | ! |
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| 27 | ! 4429 2020-02-27 15:24:30Z raasch |
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| 28 | ! bugfix: cpp-directives added for serial mode |
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| 29 | ! |
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| 30 | ! 4360 2020-01-07 11:25:50Z suehring |
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| 31 | ! OpenACC support added |
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| 32 | ! |
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| 33 | ! 4182 2019-08-22 15:20:23Z scharf |
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| 34 | ! Corrected "Former revisions" section |
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| 35 | ! |
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| 36 | ! 3655 2019-01-07 16:51:22Z knoop |
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| 37 | ! Corrected "Former revisions" section |
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| 38 | ! |
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| 39 | ! Revision 1.1 1997/07/24 11:14:03 raasch |
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| 40 | ! Initial revision |
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| 41 | ! |
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| 42 | ! |
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| 43 | ! Description: |
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| 44 | ! ------------ |
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| 45 | !> Determine the array minimum/maximum and the corresponding indices. |
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| 46 | !--------------------------------------------------------------------------------------------------! |
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| 47 | SUBROUTINE global_min_max( i1, i2, j1, j2, k1, k2, ar, mode, offset, value, value_ijk, value1, & |
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| 48 | value1_ijk ) |
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| 49 | |
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| 50 | |
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| 51 | USE indices, & |
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| 52 | ONLY: nbgp, ny, nx |
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| 53 | |
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| 54 | USE kinds |
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| 55 | |
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| 56 | USE pegrid |
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| 57 | |
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| 58 | IMPLICIT NONE |
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| 59 | |
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| 60 | CHARACTER (LEN=*) :: mode !< |
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| 61 | |
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| 62 | INTEGER(iwp) :: i !< |
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| 63 | INTEGER(iwp) :: i1 !< |
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| 64 | INTEGER(iwp) :: i2 !< |
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| 65 | #if defined( __parallel ) |
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| 66 | INTEGER(iwp) :: id_fmax !< |
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| 67 | INTEGER(iwp) :: id_fmin !< |
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| 68 | #endif |
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| 69 | INTEGER(iwp) :: j !< |
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| 70 | INTEGER(iwp) :: j1 !< |
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| 71 | INTEGER(iwp) :: j2 !< |
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| 72 | INTEGER(iwp) :: k !< |
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| 73 | INTEGER(iwp) :: k1 !< |
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| 74 | INTEGER(iwp) :: k2 !< |
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| 75 | INTEGER(iwp) :: value_ijk(3) !< |
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| 76 | |
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| 77 | INTEGER(iwp), DIMENSION(3) :: fmax_ijk !< |
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| 78 | INTEGER(iwp), DIMENSION(3) :: fmax_ijk_l !< |
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| 79 | INTEGER(iwp), DIMENSION(3) :: fmin_ijk !< |
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| 80 | INTEGER(iwp), DIMENSION(3) :: fmin_ijk_l !< |
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| 81 | |
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| 82 | INTEGER(iwp), DIMENSION(3), OPTIONAL :: value1_ijk !< |
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| 83 | |
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| 84 | REAL(wp) :: offset !< |
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| 85 | REAL(wp) :: value !< |
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| 86 | REAL(wp), OPTIONAL :: value1 !< |
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| 87 | |
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| 88 | REAL(wp) :: ar(i1:i2,j1:j2,k1:k2) !< |
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| 89 | |
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| 90 | #if defined( __ibm ) |
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| 91 | REAL(sp) :: fmax(2) !< |
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| 92 | REAL(sp) :: fmax_l(2) !< |
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| 93 | REAL(sp) :: fmin(2) !< |
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| 94 | REAL(sp) :: fmin_l(2) !< |
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| 95 | ! on 32bit-machines MPI_2REAL must not be replaced |
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| 96 | ! by MPI_2DOUBLE_PRECISION |
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| 97 | #else |
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| 98 | REAL(wp), DIMENSION(2) :: fmax !< |
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| 99 | REAL(wp), DIMENSION(2) :: fmax_l !< |
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| 100 | REAL(wp), DIMENSION(2) :: fmin !< |
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| 101 | REAL(wp), DIMENSION(2) :: fmin_l !< |
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| 102 | #endif |
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| 103 | |
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| 104 | #if defined( _OPENACC ) |
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| 105 | INTEGER(iwp) :: count_eq !< counter for locations of maximum |
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| 106 | REAL(wp) :: red !< scalar for reduction with OpenACC |
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| 107 | #endif |
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| 108 | |
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| 109 | |
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| 110 | ! |
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| 111 | !-- Determine array minimum |
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| 112 | IF ( mode == 'min' .OR. mode == 'minmax' ) THEN |
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| 113 | |
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| 114 | ! |
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| 115 | !-- Determine the local minimum |
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| 116 | fmin_ijk_l = MINLOC( ar ) |
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| 117 | fmin_ijk_l(1) = i1 + fmin_ijk_l(1) - 1 ! MINLOC assumes lowerbound = 1 |
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| 118 | fmin_ijk_l(2) = j1 + fmin_ijk_l(2) - nbgp |
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| 119 | fmin_ijk_l(3) = k1 + fmin_ijk_l(3) - nbgp |
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| 120 | fmin_l(1) = ar(fmin_ijk_l(1),fmin_ijk_l(2),fmin_ijk_l(3)) |
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| 121 | |
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| 122 | #if defined( __parallel ) |
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| 123 | fmin_l(2) = myid |
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| 124 | IF ( collective_wait ) CALL MPI_BARRIER( comm2d, ierr ) |
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| 125 | CALL MPI_ALLREDUCE( fmin_l, fmin, 1, MPI_2REAL, MPI_MINLOC, comm2d, ierr ) |
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| 126 | |
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| 127 | ! |
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| 128 | !-- Determine the global minimum. Result stored on PE0. |
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| 129 | id_fmin = fmin(2) |
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| 130 | IF ( id_fmin /= 0 ) THEN |
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| 131 | IF ( myid == 0 ) THEN |
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| 132 | CALL MPI_RECV( fmin_ijk, 3, MPI_INTEGER, id_fmin, 0, comm2d, status, ierr ) |
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| 133 | ELSEIF ( myid == id_fmin ) THEN |
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| 134 | CALL MPI_SEND( fmin_ijk_l, 3, MPI_INTEGER, 0, 0, comm2d, ierr ) |
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| 135 | ENDIF |
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| 136 | ELSE |
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| 137 | fmin_ijk = fmin_ijk_l |
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| 138 | ENDIF |
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| 139 | ! |
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| 140 | !-- Send the indices of the just determined array minimum to other PEs |
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| 141 | CALL MPI_BCAST( fmin_ijk, 3, MPI_INTEGER, 0, comm2d, ierr ) |
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| 142 | #else |
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| 143 | fmin(1) = fmin_l(1) |
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| 144 | fmin_ijk = fmin_ijk_l |
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| 145 | #endif |
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| 146 | |
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| 147 | ENDIF |
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| 148 | |
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| 149 | ! |
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| 150 | !-- Determine array maximum |
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| 151 | IF ( mode == 'max' .OR. mode == 'minmax' ) THEN |
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| 152 | |
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| 153 | ! |
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| 154 | !-- Determine the local maximum |
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| 155 | fmax_ijk_l = MAXLOC( ar ) |
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| 156 | fmax_ijk_l(1) = i1 + fmax_ijk_l(1) - 1 ! MAXLOC assumes lowerbound = 1 |
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| 157 | fmax_ijk_l(2) = j1 + fmax_ijk_l(2) - nbgp |
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| 158 | fmax_ijk_l(3) = k1 + fmax_ijk_l(3) - nbgp |
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| 159 | fmax_l(1) = ar(fmax_ijk_l(1),fmax_ijk_l(2),fmax_ijk_l(3)) |
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| 160 | |
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| 161 | #if defined( __parallel ) |
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| 162 | fmax_l(2) = myid |
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| 163 | IF ( collective_wait ) CALL MPI_BARRIER( comm2d, ierr ) |
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| 164 | CALL MPI_ALLREDUCE( fmax_l, fmax, 1, MPI_2REAL, MPI_MAXLOC, comm2d, ierr ) |
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| 165 | |
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| 166 | ! |
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| 167 | !-- Determine the global maximum. Result stored on PE0. |
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| 168 | id_fmax = fmax(2) |
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| 169 | IF ( id_fmax /= 0 ) THEN |
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| 170 | IF ( myid == 0 ) THEN |
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| 171 | CALL MPI_RECV( fmax_ijk, 3, MPI_INTEGER, id_fmax, 0, comm2d, status, ierr ) |
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| 172 | ELSEIF ( myid == id_fmax ) THEN |
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| 173 | CALL MPI_SEND( fmax_ijk_l, 3, MPI_INTEGER, 0, 0, comm2d, ierr ) |
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| 174 | ENDIF |
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| 175 | ELSE |
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| 176 | fmax_ijk = fmax_ijk_l |
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| 177 | ENDIF |
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| 178 | ! |
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| 179 | !-- Send the indices of the just determined array maximum to other PEs |
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| 180 | CALL MPI_BCAST( fmax_ijk, 3, MPI_INTEGER, 0, comm2d, ierr ) |
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| 181 | #else |
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| 182 | fmax(1) = fmax_l(1) |
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| 183 | fmax_ijk = fmax_ijk_l |
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| 184 | #endif |
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| 185 | |
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| 186 | ENDIF |
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| 187 | |
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| 188 | ! |
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| 189 | !-- Determine absolute array maximum |
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| 190 | IF ( mode == 'abs' ) THEN |
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| 191 | |
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| 192 | #if defined( _OPENACC ) |
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| 193 | red = 0.0_wp |
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| 194 | !$ACC PARALLEL LOOP COLLAPSE(3) PRIVATE(i, j, k) & |
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| 195 | !$ACC PRESENT(ar) COPY(red) REDUCTION(MAX: red) |
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| 196 | DO k = k1, k2 |
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| 197 | DO j = j1, j2 |
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| 198 | DO i = i1, i2 |
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| 199 | IF ( ABS( ar(i,j,k) ) > red ) THEN |
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| 200 | red = ABS( ar(i,j,k) ) |
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| 201 | ENDIF |
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| 202 | ENDDO |
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| 203 | ENDDO |
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| 204 | ENDDO |
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| 205 | fmax_l(1) = red |
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| 206 | |
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| 207 | ! |
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| 208 | !-- Determine the maximum's position and count how often it is found. |
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| 209 | count_eq = 0 |
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| 210 | !$ACC PARALLEL LOOP COLLAPSE(3) PRIVATE(i, j, k) & |
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| 211 | !$ACC PRESENT(ar) COPY(fmax_ijk_l(1:3), count_eq) & |
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| 212 | !$ACC REDUCTION(+:count_eq) |
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| 213 | DO k = k1, k2 |
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| 214 | DO j = j1, j2 |
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| 215 | DO i = i1, i2 |
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| 216 | IF ( ABS( ar(i,j,k) ) == red ) THEN |
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| 217 | fmax_ijk_l(1) = i |
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| 218 | fmax_ijk_l(2) = j |
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| 219 | fmax_ijk_l(3) = k |
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| 220 | count_eq = count_eq + 1 |
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| 221 | ENDIF |
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| 222 | ENDDO |
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| 223 | ENDDO |
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| 224 | ENDDO |
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| 225 | |
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| 226 | IF ( count_eq == 1 ) THEN |
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| 227 | ! |
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| 228 | !-- We found a single maximum element and correctly got its position. Transfer its value to |
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| 229 | !-- handle the negative case correctly. |
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| 230 | !$ACC UPDATE HOST(ar(fmax_ijk_l(1):fmax_ijk_l(1),fmax_ijk_l(2),fmax_ijk_l(3))) |
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| 231 | ELSE |
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| 232 | ! |
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| 233 | !-- We found no maximum element (?) or multiple, so the position is not correct. |
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| 234 | !-- Copy the full array to the host and determine the maximum sequentially... |
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| 235 | !$ACC UPDATE HOST(ar(i1:i2,j1:j2,k1:k2)) |
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| 236 | #endif |
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| 237 | |
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| 238 | ! |
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| 239 | !-- Determine the local absolut maximum |
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| 240 | fmax_l(1) = 0.0_wp |
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| 241 | fmax_ijk_l(1) = i1 |
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| 242 | fmax_ijk_l(2) = j1 |
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| 243 | fmax_ijk_l(3) = k1 |
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| 244 | DO k = k1, k2 |
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| 245 | DO j = j1, j2 |
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| 246 | DO i = i1, i2 |
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| 247 | IF ( ABS( ar(i,j,k) ) > fmax_l(1) ) THEN |
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| 248 | fmax_l(1) = ABS( ar(i,j,k) ) |
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| 249 | fmax_ijk_l(1) = i |
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| 250 | fmax_ijk_l(2) = j |
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| 251 | fmax_ijk_l(3) = k |
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| 252 | ENDIF |
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| 253 | ENDDO |
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| 254 | ENDDO |
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| 255 | ENDDO |
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| 256 | |
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| 257 | #if defined( _OPENACC ) |
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| 258 | ! |
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| 259 | !-- Close ELSE case from above |
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| 260 | ENDIF |
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| 261 | #endif |
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| 262 | |
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| 263 | ! |
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| 264 | !-- Set a flag in case that the determined value is negative. |
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| 265 | !-- A constant offset has to be subtracted in order to handle the special case i=0 correctly. |
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| 266 | IF ( ar(fmax_ijk_l(1),fmax_ijk_l(2),fmax_ijk_l(3)) < 0.0_wp ) THEN |
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| 267 | fmax_ijk_l(1) = -fmax_ijk_l(1) - 10 |
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| 268 | ENDIF |
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| 269 | |
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| 270 | #if defined( __parallel ) |
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| 271 | fmax_l(2) = myid |
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| 272 | IF ( collective_wait ) CALL MPI_BARRIER( comm2d, ierr ) |
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| 273 | CALL MPI_ALLREDUCE( fmax_l, fmax, 1, MPI_2REAL, MPI_MAXLOC, comm2d, ierr ) |
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| 274 | |
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| 275 | ! |
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| 276 | !-- Determine the global absolut maximum. Result stored on PE0. |
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| 277 | id_fmax = fmax(2) |
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| 278 | IF ( id_fmax /= 0 ) THEN |
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| 279 | IF ( myid == 0 ) THEN |
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| 280 | CALL MPI_RECV( fmax_ijk, 3, MPI_INTEGER, id_fmax, 0, comm2d, status, ierr ) |
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| 281 | ELSEIF ( myid == id_fmax ) THEN |
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| 282 | CALL MPI_SEND( fmax_ijk_l, 3, MPI_INTEGER, 0, 0, comm2d, ierr ) |
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| 283 | ENDIF |
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| 284 | ELSE |
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| 285 | fmax_ijk = fmax_ijk_l |
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| 286 | ENDIF |
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| 287 | ! |
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| 288 | !-- Send the indices of the just determined absolut maximum to other PEs |
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| 289 | CALL MPI_BCAST( fmax_ijk, 3, MPI_INTEGER, 0, comm2d, ierr ) |
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| 290 | #else |
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| 291 | fmax(1) = fmax_l(1) |
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| 292 | fmax_ijk = fmax_ijk_l |
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| 293 | #endif |
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| 294 | |
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| 295 | ENDIF |
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| 296 | |
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| 297 | ! |
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| 298 | !-- Determine absolute maximum of ( array - offset ) |
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| 299 | IF ( mode == 'absoff' ) THEN |
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| 300 | |
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| 301 | ! |
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| 302 | !-- Determine the local absolut maximum |
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| 303 | fmax_l(1) = 0.0_wp |
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| 304 | fmax_ijk_l(1) = i1 |
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| 305 | fmax_ijk_l(2) = j1 |
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| 306 | fmax_ijk_l(3) = k1 |
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| 307 | DO k = k1, k2 |
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| 308 | DO j = j1, j2 |
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| 309 | ! |
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| 310 | !-- Attention: the lowest gridpoint is excluded here, because there is no advection at |
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| 311 | !-- ---------- nzb=0 and mode 'absoff' is only used for calculating u,v extrema for |
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| 312 | !-- CFL-criteria. |
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| 313 | DO i = i1+1, i2 |
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| 314 | IF ( ABS( ar(i,j,k) - offset ) > fmax_l(1) ) THEN |
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| 315 | fmax_l(1) = ABS( ar(i,j,k) - offset ) |
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| 316 | fmax_ijk_l(1) = i |
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| 317 | fmax_ijk_l(2) = j |
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| 318 | fmax_ijk_l(3) = k |
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| 319 | ENDIF |
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| 320 | ENDDO |
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| 321 | ENDDO |
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| 322 | ENDDO |
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| 323 | |
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| 324 | ! |
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| 325 | !-- Set a flag in case that the determined value is negative. |
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| 326 | !-- A constant offset has to be subtracted in order to handle the special case i=0 correctly. |
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| 327 | IF ( ar(fmax_ijk_l(1),fmax_ijk_l(2),fmax_ijk_l(3)) < 0.0_wp ) THEN |
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| 328 | fmax_ijk_l(1) = -fmax_ijk_l(1) - 10 |
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| 329 | ENDIF |
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| 330 | |
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| 331 | #if defined( __parallel ) |
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| 332 | fmax_l(2) = myid |
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| 333 | IF ( collective_wait ) CALL MPI_BARRIER( comm2d, ierr ) |
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| 334 | CALL MPI_ALLREDUCE( fmax_l, fmax, 1, MPI_2REAL, MPI_MAXLOC, comm2d, ierr ) |
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| 335 | |
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| 336 | ! |
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| 337 | !-- Determine the global absolut maximum. Result stored on PE0. |
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| 338 | id_fmax = fmax(2) |
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| 339 | IF ( id_fmax /= 0 ) THEN |
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| 340 | IF ( myid == 0 ) THEN |
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| 341 | CALL MPI_RECV( fmax_ijk, 3, MPI_INTEGER, id_fmax, 0, comm2d, status, ierr ) |
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| 342 | ELSEIF ( myid == id_fmax ) THEN |
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| 343 | CALL MPI_SEND( fmax_ijk_l, 3, MPI_INTEGER, 0, 0, comm2d, ierr ) |
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| 344 | ENDIF |
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| 345 | ELSE |
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| 346 | fmax_ijk = fmax_ijk_l |
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| 347 | ENDIF |
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| 348 | ! |
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| 349 | !-- Send the indices of the just determined absolut maximum to other PEs |
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| 350 | CALL MPI_BCAST( fmax_ijk, 3, MPI_INTEGER, 0, comm2d, ierr ) |
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| 351 | #else |
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| 352 | fmax(1) = fmax_l(1) |
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| 353 | fmax_ijk = fmax_ijk_l |
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| 354 | #endif |
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| 355 | |
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| 356 | ENDIF |
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| 357 | |
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| 358 | ! |
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| 359 | !-- Determine output parameters |
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| 360 | SELECT CASE( mode ) |
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| 361 | |
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| 362 | CASE( 'min' ) |
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| 363 | |
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| 364 | value = fmin(1) |
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| 365 | value_ijk = fmin_ijk |
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| 366 | |
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| 367 | CASE( 'max' ) |
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| 368 | |
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| 369 | value = fmax(1) |
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| 370 | value_ijk = fmax_ijk |
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| 371 | |
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| 372 | CASE( 'minmax' ) |
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| 373 | |
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| 374 | value = fmin(1) |
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| 375 | value_ijk = fmin_ijk |
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| 376 | value1 = fmax(1) |
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| 377 | value1_ijk = fmax_ijk |
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| 378 | |
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| 379 | CASE( 'abs', 'absoff' ) |
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| 380 | |
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| 381 | value = fmax(1) |
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| 382 | value_ijk = fmax_ijk |
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| 383 | IF ( fmax_ijk(1) < 0 ) THEN |
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| 384 | value = -value |
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| 385 | value_ijk(1) = -value_ijk(1) - 10 !??? |
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| 386 | ENDIF |
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| 387 | |
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| 388 | END SELECT |
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| 389 | |
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| 390 | ! |
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| 391 | !-- Limit index values to the range 0..nx, 0..ny |
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| 392 | IF ( value_ijk(3) < 0 ) value_ijk(3) = nx +1 + value_ijk(3) |
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| 393 | IF ( value_ijk(3) > nx ) value_ijk(3) = value_ijk(3) - (nx+1) |
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| 394 | IF ( value_ijk(2) < 0 ) value_ijk(2) = ny +1 + value_ijk(2) |
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| 395 | IF ( value_ijk(2) > ny ) value_ijk(2) = value_ijk(2) - (ny+1) |
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| 396 | |
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| 397 | |
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| 398 | END SUBROUTINE global_min_max |
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