!> @file random_generator_parallel_mod.f90 !--------------------------------------------------------------------------------------------------! ! This file is part of the PALM model system. ! ! 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 ! . ! ! Copyright 1997-2021 Leibniz Universitaet Hannover !--------------------------------------------------------------------------------------------------! ! ! ! Current revisions: ! ----------------- ! ! ! Former revisions: ! ----------------- ! $Id: random_generator_parallel_mod.f90 4828 2021-01-05 11:21:41Z raasch $ ! File re-formatted to follow the PALM coding standard ! ! 4545 2020-05-22 13:17:57Z schwenkel ! Add generator (using parallel mode) returning gaussian distributed random number ! ! 4438 2020-03-03 20:49:28Z raasch ! - Rename variables to avoid confusion with subdomain grid indices ! - Some formatting adjustments ! - New routine to initialize spatial 1D-arrays independent on the 2D random-number array ! ! 4360 2020-01-07 11:25:50Z suehring ! Corrected "Former revisions" section ! ! 3655 2019-01-07 16:51:22Z knoop ! Unused variable removed ! ! 1400 2014-05-09 14:03:54Z knoop ! Initial revision ! ! !--------------------------------------------------------------------------------------------------! ! Description: ! ------------ !> This module contains and supports the random number generating routine ran_parallel. !> ran_parallel returns a uniform random deviate between 0.0 and 1.0 (exclusive of the end point !> values). Moreover, it contains a routine returning a normally distributed random number with mean !> zero and unity standard deviation. Additionally, it provides the generator with five integers for !> use as initial state space. The first tree integers (iran, jran, kran) are maintained as non !> negative values, while the last two (mran, nran) have 32-bit nonzero values. Also provided by !> this module is support for initializing or reinitializing the state space to a desired standard !> sequence number, hashing the initial values to random values and allocating and deallocating the !> internal workspace. !> !> This routine is taken from the "numerical recipies vol. 2" !--------------------------------------------------------------------------------------------------! MODULE random_generator_parallel USE kinds IMPLICIT NONE INTEGER(isp), SAVE :: lenran = 0 !< INTEGER(isp), SAVE :: seq = 0 !< INTEGER(isp), SAVE :: iran0 !< INTEGER(isp), SAVE :: jran0 !< INTEGER(isp), SAVE :: kran0 !< INTEGER(isp), SAVE :: mran0 !< INTEGER(isp), SAVE :: nran0 !< INTEGER(isp), SAVE :: rans !< INTEGER(isp), DIMENSION(:, :), POINTER, SAVE :: ranseeds !< INTEGER(isp), DIMENSION(:), POINTER, SAVE :: iran !< INTEGER(isp), DIMENSION(:), POINTER, SAVE :: jran !< INTEGER(isp), DIMENSION(:), POINTER, SAVE :: kran !< INTEGER(isp), DIMENSION(:), POINTER, SAVE :: mran !< INTEGER(isp), DIMENSION(:), POINTER, SAVE :: nran !< INTEGER(isp), DIMENSION(:), POINTER, SAVE :: ranv !< INTEGER(isp), DIMENSION(:,:), ALLOCATABLE :: id_random_array !< INTEGER(isp), DIMENSION(:,:,:), ALLOCATABLE :: seq_random_array !< REAL(wp), SAVE :: amm !< REAL(wp) :: random_dummy = 0.0 !< INTERFACE init_parallel_random_generator MODULE PROCEDURE init_parallel_random_generator_1d MODULE PROCEDURE init_parallel_random_generator_2d END INTERFACE INTERFACE random_number_parallel MODULE PROCEDURE ran0_s END INTERFACE INTERFACE random_number_parallel_gauss MODULE PROCEDURE gasdev_s END INTERFACE INTERFACE random_seed_parallel MODULE PROCEDURE random_seed_parallel END INTERFACE INTERFACE ran_hash MODULE PROCEDURE ran_hash_v END INTERFACE INTERFACE reallocate MODULE PROCEDURE reallocate_iv,reallocate_im END INTERFACE INTERFACE arth MODULE PROCEDURE arth_i END INTERFACE PRIVATE PUBLIC random_number_parallel, & random_seed_parallel, & random_dummy, & id_random_array, & seq_random_array, & init_parallel_random_generator, & random_number_parallel_gauss CONTAINS !--------------------------------------------------------------------------------------------------! ! Description: ! ------------ !> Initialize the parallel random number generator for a 1-dimensional array. !--------------------------------------------------------------------------------------------------! SUBROUTINE init_parallel_random_generator_1d( nxy, ns, ne, id_rand, seq_rand ) USE control_parameters, & ONLY: ensemble_member_nr INTEGER(isp), INTENT(IN) :: nxy !< constant scaling with grid dimensions INTEGER(isp), INTENT(IN) :: ns !< start index on subdomain INTEGER(isp), INTENT(IN) :: ne !< end index on subdomain INTEGER(iwp) :: j !< loop index INTEGER(isp), DIMENSION(ns:ne) :: id_rand !< initial IDs INTEGER(isp), DIMENSION(5,ns:ne) :: seq_rand !< initial random seeds ! !-- Asigning an ID to every vertical gridpoint column dependig on the ensemble run number. DO j = ns, ne id_rand(j) = j * ( nxy + 1.0_wp ) + 1.0_wp + 1E6 * ( ensemble_member_nr - 1000 ) ENDDO ! !-- Initializing with random_seed_parallel for every vertical gridpoint column. random_dummy = 0 DO j = ns, ne CALL random_seed_parallel( random_sequence=id_rand(j) ) CALL random_number_parallel( random_dummy ) CALL random_seed_parallel( get=seq_rand(:,j) ) ENDDO END SUBROUTINE init_parallel_random_generator_1d !--------------------------------------------------------------------------------------------------! ! Description: ! ------------ !> Initialize the parallel random number generator for a specific subdomain. !--------------------------------------------------------------------------------------------------! SUBROUTINE init_parallel_random_generator_2d( nx_l, nys_l, nyn_l, nxl_l, nxr_l ) USE kinds USE control_parameters, & ONLY: ensemble_member_nr IMPLICIT NONE INTEGER(isp), INTENT(IN) :: nx_l !< constant INTEGER(isp), INTENT(IN) :: nys_l !< local lower subdomain bound index in y-direction INTEGER(isp), INTENT(IN) :: nyn_l !< local upper subdomain bound index in y-direction INTEGER(isp), INTENT(IN) :: nxl_l !< local lower subdomain bound index in x-direction INTEGER(isp), INTENT(IN) :: nxr_l !< local upper subdomain bound index in x-direction INTEGER(iwp) :: i !< grid index x-direction INTEGER(iwp) :: j !< grid index y-direction !-- Allocate ID-array and state-space-array ALLOCATE ( seq_random_array(5,nys_l:nyn_l,nxl_l:nxr_l) ) ALLOCATE ( id_random_array(nys_l:nyn_l,nxl_l:nxr_l) ) seq_random_array = 0 id_random_array = 0 !-- Asigning an ID to every vertical gridpoint column dependig on the ensemble run number. DO i = nxl_l, nxr_l DO j = nys_l, nyn_l id_random_array(j,i) = j * ( nx_l + 1.0_wp ) + i + 1.0_wp + 1E6 * & ( ensemble_member_nr - 1000 ) ENDDO ENDDO !-- Initializing with random_seed_parallel for every vertical gridpoint column. random_dummy = 0 DO i = nxl_l, nxr_l DO j = nys_l, nyn_l CALL random_seed_parallel( random_sequence = id_random_array(j,i) ) CALL random_number_parallel( random_dummy ) CALL random_seed_parallel( get = seq_random_array(:,j,i) ) ENDDO ENDDO END SUBROUTINE init_parallel_random_generator_2d !--------------------------------------------------------------------------------------------------! ! Description: ! ------------ !> Lagged Fibonacci generator combined with a Marsaglia shift sequence. Returns as harvest a uniform !> random deviate between 0.0 and 1.0 (exclusive of the end point values). This generator has the !> same calling and initialization conventions as Fortran 90's random_number routine. !> Use random_seed_parallel to initialize or reinitialize to a particular sequence. !> The period of this generator is about 2.0 x 10^28, and it fully vectorizes. !> Validity of the integer model assumed by this generator is tested at initialization. !--------------------------------------------------------------------------------------------------! SUBROUTINE ran0_s( harvest ) USE kinds IMPLICIT NONE REAL(wp), INTENT(OUT) :: harvest !< ! !-- Initialization routine in ran_state. IF ( lenran < 1 ) CALL ran_init( 1 ) ! !-- Update Fibonacci generator, which has period p^2 + p + 1, p = 2^31 - 69. rans = iran0 - kran0 IF ( rans < 0 ) rans = rans + 2147483579_isp iran0 = jran0 jran0 = kran0 kran0 = rans ! !-- Update Marsaglia shift sequence with period 2^32 - 1. nran0 = IEOR( nran0, ISHFT( nran0, 13 ) ) nran0 = IEOR( nran0, ISHFT( nran0, -17 ) ) nran0 = IEOR( nran0, ISHFT( nran0, 5 ) ) ! !-- Combine the generators. rans = IEOR( nran0, rans ) ! !-- Make the result positive definite (note that amm is negative). harvest = amm * MERGE( rans, NOT( rans ), rans < 0 ) END SUBROUTINE ran0_s !--------------------------------------------------------------------------------------------------! ! Description: ! ------------ !> Returns in harvest a normally distributed deviate with zero mean and unit variance, using ran0_s !> as the source of uniform deviates. Following Numerical Recipes in Fortran90 (Press et al., 2nd !> edition, 1996, pp 1152ff). Note, instead of ran1_s, ran0_s is used. !--------------------------------------------------------------------------------------------------! SUBROUTINE gasdev_s( harvest ) REAL(wp), INTENT(OUT) :: harvest !< REAL(wp) :: rsq !< REAL(wp) :: v1 !< REAL(wp) :: v2 !< REAL(wp), SAVE :: g !< LOGICAL, SAVE :: gaus_stored = .FALSE. !< ! !-- We have an extra deviate handy, so return it, and unset the flag. IF ( gaus_stored ) THEN harvest = g gaus_stored = .FALSE. ! !-- We don’t have an extra deviate handy, so pick two uniform numbers in the square extending !-- from -1 to +1 in each direction ELSE DO CALL ran0_s( v1 ) CALL ran0_s( v2 ) v1 = 2.0_wp * v1 - 1.0_wp v2 = 2.0_wp * v2 - 1.0_wp ! !-- See if they are in the unit circle rsq = v1**2 + v2**2 ! !-- Otherwise try again. IF ( rsq > 0.0 .AND. rsq < 1.0 ) EXIT ENDDO ! !-- Now make the Box-Muller transformation to get two normal deviates. !-- Return one and save the other for next time. Set flag. rsq = SQRT( - 2.0_sp * LOG( rsq ) / rsq ) harvest = v1 * rsq g = v2 * rsq gaus_stored = .TRUE. ENDIF END SUBROUTINE gasdev_s !--------------------------------------------------------------------------------------------------! ! Description: ! ------------ !> Initialize or reinitialize the random generator state space to vectors of size length. !> The saved variable seq is hashed (via calls to the module routine ran_hash) to create unique !> starting seeds, different for each vector component. !--------------------------------------------------------------------------------------------------! SUBROUTINE ran_init( length ) USE kinds IMPLICIT NONE INTEGER(isp), INTENT(IN) :: length !< INTEGER(isp) :: hg !< INTEGER(isp) :: hgm !< INTEGER(isp) :: hgng !< INTEGER(isp) :: new !< INTEGER(isp) :: j !< INTEGER(isp) :: hgt !< ! !-- Simply return if enough space is already allocated. IF ( length < lenran ) RETURN hg = HUGE( 1_isp ) hgm = - hg hgng = hgm - 1 hgt = hg !-- The following lines check that kind value isp is in fact a 32-bit integer with the usual !-- properties that we expect it to have (under negation and wrap-around addition). !-- If all of these tests are satisfied, then the routines that use this module are portable, even !-- though they go beyond Fortran 90's integer model. IF ( hg /= 2147483647 ) CALL ran_error( 'arithmetic assumption 1 failed' ) IF ( hgng >= 0 ) CALL ran_error( 'arithmetic assumption 2 failed' ) IF ( hgt + 1 /= hgng ) CALL ran_error( 'arithmetic assumption 3 failed' ) IF ( NOT( hg ) >= 0 ) CALL ran_error( 'arithmetic assumption 4 failed' ) IF ( NOT( hgng ) < 0 ) CALL ran_error( 'arithmetic assumption 5 failed' ) IF ( hg + hgng >= 0 ) CALL ran_error( 'arithmetic assumption 6 failed' ) IF ( NOT( - 1_isp ) < 0 ) CALL ran_error( 'arithmetic assumption 7 failed' ) IF ( NOT( 0_isp ) >= 0 ) CALL ran_error( 'arithmetic assumption 8 failed' ) IF ( NOT( 1_isp ) >= 0 ) CALL ran_error( 'arithmetic assumption 9 failed' ) IF ( lenran > 0 ) THEN ! Reallocate space, or ... ranseeds => reallocate( ranseeds, length, 5 ) ranv => reallocate( ranv, length - 1 ) new = lenran + 1 ELSE ! Allocate space. ALLOCATE( ranseeds(length,5) ) ALLOCATE( ranv(length-1) ) new = 1 !- Index of first location not yet initialized. amm = NEAREST( 1.0_wp, - 1.0_wp ) / hgng ! !-- Use of nearest is to ensure that returned random deviates are strictly less than 1.0. IF ( amm * hgng >= 1.0 .OR. amm * hgng <= 0.0 ) & CALL ran_error( 'arithmetic assumption 10 failed' ) END IF ! !-- Set starting values, unique by seq and vector component. ranseeds(new:,1) = seq ranseeds(new:,2:5) = SPREAD( arth( new, 1, SIZE( ranseeds(new:,1) ) ), 2, 4 ) DO j = 1, 4 ! Hash them. CALL ran_hash( ranseeds(new:,j), ranseeds(new:,j+1) ) END DO WHERE ( ranseeds(new:,1:3) < 0 ) & ranseeds(new:,1:3) = NOT( ranseeds(new:,1:3) ) ! Enforce nonnegativity. WHERE ( ranseeds(new:,4:5) == 0 ) ranseeds(new:,4:5) = 1 ! Enforce nonzero. IF ( new == 1 ) THEN ! Set scalar seeds. iran0 = ranseeds(1,1) jran0 = ranseeds(1,2) kran0 = ranseeds(1,3) mran0 = ranseeds(1,4) nran0 = ranseeds(1,5) rans = nran0 END IF IF ( length > 1 ) THEN ! Point to vector seeds. iran => ranseeds(2:,1) jran => ranseeds(2:,2) kran => ranseeds(2:,3) mran => ranseeds(2:,4) nran => ranseeds(2:,5) ranv = nran END IF lenran = length END SUBROUTINE ran_init !--------------------------------------------------------------------------------------------------! ! Description: ! ------------ !> User interface to release the workspace used by the random number routines. !--------------------------------------------------------------------------------------------------! SUBROUTINE ran_deallocate IF ( lenran > 0 ) THEN DEALLOCATE( ranseeds, ranv ) NULLIFY( ranseeds, ranv, iran, jran, kran, mran, nran ) lenran = 0 END IF END SUBROUTINE ran_deallocate !--------------------------------------------------------------------------------------------------! ! Description: ! ------------ !> User interface for seeding the random number routines. !> Syntax is exactly like Fortran 90's random_seed routine, with one additional argument keyword: !> random_sequence, set to any integer value, causes an immediate new initialization, seeded by that !> integer. !--------------------------------------------------------------------------------------------------! SUBROUTINE random_seed_parallel( random_sequence, state_size, put, get ) IMPLICIT NONE INTEGER(isp), OPTIONAL, INTENT(IN) :: random_sequence !< INTEGER(isp), OPTIONAL, INTENT(OUT) :: state_size !< INTEGER(isp), DIMENSION(:), OPTIONAL, INTENT(IN) :: put !< INTEGER(isp), DIMENSION(:), OPTIONAL, INTENT(OUT) :: get !< IF ( PRESENT( state_size ) ) THEN state_size = 5 * lenran ELSE IF ( PRESENT( put ) ) THEN IF ( lenran == 0 ) RETURN ranseeds = RESHAPE( put, SHAPE( ranseeds ) ) ! !-- Enforce nonnegativity and nonzero conditions on any user-supplied seeds. WHERE ( ranseeds(:,1:3) < 0 ) ranseeds(:,1:3) = NOT( ranseeds(:,1:3) ) WHERE ( ranseeds(:,4:5) == 0 ) ranseeds(:,4:5) = 1 iran0 = ranseeds(1,1) jran0 = ranseeds(1,2) kran0 = ranseeds(1,3) mran0 = ranseeds(1,4) nran0 = ranseeds(1,5) ELSE IF ( PRESENT( get ) ) THEN IF ( lenran == 0 ) RETURN ranseeds(1,1:5) = (/ iran0, jran0, kran0, mran0, nran0 /) get = RESHAPE( ranseeds, SHAPE( get ) ) ELSE IF ( PRESENT( random_sequence ) ) THEN CALL ran_deallocate seq = random_sequence END IF END SUBROUTINE random_seed_parallel !--------------------------------------------------------------------------------------------------! ! Description: ! ------------ !> DES-like hashing of two 32-bit integers, using shifts, xor's, and adds to make the internal !> nonlinear function. !--------------------------------------------------------------------------------------------------! SUBROUTINE ran_hash_v( il, ir ) IMPLICIT NONE INTEGER(isp), DIMENSION(:), INTENT(INOUT) :: il !< INTEGER(isp), DIMENSION(:), INTENT(INOUT) :: ir !< INTEGER(isp), DIMENSION(size(il)) :: is !< INTEGER(isp) :: j !< DO j = 1, 4 is = ir ir = IEOR( ir, ISHFT( ir, 5 ) ) + 1422217823 ir = IEOR( ir, ISHFT( ir, - 16 ) ) + 1842055030 ir = IEOR( ir, ISHFT( ir, 9 ) ) + 80567781 ir = IEOR( il, ir ) il = is END DO END SUBROUTINE ran_hash_v !--------------------------------------------------------------------------------------------------! ! Description: ! ------------ !> User interface to process error-messages produced by the random_number_parallel module. !--------------------------------------------------------------------------------------------------! SUBROUTINE ran_error( string ) USE control_parameters, & ONLY: message_string CHARACTER(LEN=*), INTENT(IN) :: string !< Error message string message_string = 'incompatible integer arithmetic: ' // TRIM( string ) CALL message( 'ran_init', 'PA0453', 1, 2, 0, 6, 0 ) END SUBROUTINE ran_error !--------------------------------------------------------------------------------------------------! ! Description: ! ------------ !> Reallocates the generators state space "ranseeds" to vectors of size length. !--------------------------------------------------------------------------------------------------! FUNCTION reallocate_iv( p, n ) USE control_parameters, & ONLY: message_string INTEGER(isp), DIMENSION(:), POINTER :: p !< INTEGER(isp), DIMENSION(:), POINTER :: reallocate_iv !< INTEGER(isp), INTENT(IN) :: n !< INTEGER(isp) :: nold !< INTEGER(isp) :: ierr !< ALLOCATE( reallocate_iv(n), stat = ierr ) IF ( ierr /= 0 ) THEN message_string = 'problem in attempt to allocate memory' CALL message( 'reallocate_iv', 'PA0454', 1, 2, 0, 6, 0 ) END IF IF ( .NOT. ASSOCIATED( p ) ) RETURN nold = SIZE( p ) reallocate_iv(1:MIN( nold, n )) = p(1:MIN( nold, n )) DEALLOCATE( p ) END FUNCTION reallocate_iv FUNCTION reallocate_im( p, n, m ) USE control_parameters, & ONLY: message_string INTEGER(isp), DIMENSION(:,:), POINTER :: p !< INTEGER(isp), DIMENSION(:,:), POINTER :: reallocate_im !< INTEGER(isp), INTENT(IN) :: m !< INTEGER(isp), INTENT(IN) :: n !< INTEGER(isp) :: mold !< INTEGER(isp) :: nold !< INTEGER(isp) :: ierr !< ALLOCATE( reallocate_im(n,m), stat = ierr ) IF ( ierr /= 0 ) THEN message_string = 'problem in attempt to allocate memory' CALL message( 'reallocate_im', 'PA0454', 1, 2, 0, 6, 0 ) END IF IF ( .NOT. ASSOCIATED( p ) ) RETURN nold = SIZE( p, 1 ) mold = SIZE( p, 2 ) reallocate_im(1:MIN( nold, n ),1:MIN( mold, m )) = p(1:MIN( nold, n ),1:MIN( mold, m )) DEALLOCATE(p) END FUNCTION reallocate_im !--------------------------------------------------------------------------------------------------! ! Description: ! ------------ !> Reallocates the generators state space "ranseeds" to vectors of size length. !--------------------------------------------------------------------------------------------------! FUNCTION arth_i( first, increment, n ) INTEGER(isp), INTENT(IN) :: first !< INTEGER(isp), INTENT(IN) :: increment !< INTEGER(isp), INTENT(IN) :: n !< INTEGER(isp), DIMENSION(n) :: arth_i !< INTEGER(isp) :: k !< INTEGER(isp) :: k2 !< INTEGER(isp) :: temp !< INTEGER(isp), PARAMETER :: npar_arth = 16 !< INTEGER(isp), PARAMETER :: npar2_arth = 8 !< IF ( n > 0 ) arth_i(1) = first IF ( n <= npar_arth ) THEN DO k = 2, n arth_i(k) = arth_i(k-1) + increment END DO ELSE DO k = 2, npar2_arth arth_i(k) = arth_i(k-1) + increment END DO temp = increment * npar2_arth k = npar2_arth DO IF ( k >= n ) EXIT k2 = k + k arth_i(k+1:MIN( k2, n )) = temp + arth_i(1:MIN( k, n - k )) temp = temp + temp k = k2 END DO END IF END FUNCTION arth_i END MODULE random_generator_parallel