Line data    Source code

       1             : !--------------------------------------------------------------------------------------------------!
       2             : !   CP2K: A general program to perform molecular dynamics simulations                              !
       3             : !   Copyright 2000-2024 CP2K developers group <https://cp2k.org>                                   !
       4             : !                                                                                                  !
       5             : !   SPDX-License-Identifier: GPL-2.0-or-later                                                      !
       6             : !--------------------------------------------------------------------------------------------------!
       7             : 
       8             : ! **************************************************************************************************
       9             : !> \brief Storage to keep precomputed surface Green's functions
      10             : ! **************************************************************************************************
      11             : MODULE negf_green_cache
      12             :    USE cp_cfm_types,                    ONLY: cp_cfm_release,&
      13             :                                               cp_cfm_type
      14             :    USE kinds,                           ONLY: dp
      15             :    USE util,                            ONLY: sort
      16             : #include "./base/base_uses.f90"
      17             : 
      18             :    IMPLICIT NONE
      19             :    PRIVATE
      20             : 
      21             :    CHARACTER(len=*), PARAMETER, PRIVATE :: moduleN = 'negf_green_cache'
      22             :    LOGICAL, PARAMETER, PRIVATE          :: debug_this_module = .TRUE.
      23             : 
      24             :    PUBLIC :: green_functions_cache_type
      25             : 
      26             :    PUBLIC :: green_functions_cache_expand, &
      27             :              green_functions_cache_reorder, &
      28             :              green_functions_cache_release
      29             : 
      30             : ! **************************************************************************************************
      31             : !> \brief Storage to keep surface Green's functions.
      32             : !> \author Sergey Chulkov
      33             : ! **************************************************************************************************
      34             :    TYPE green_functions_cache_type
      35             :       !> retarded surface Green's functions [ncontacts, nnodes]
      36             :       TYPE(cp_cfm_type), ALLOCATABLE, DIMENSION(:, :)   :: g_surf_contacts
      37             :       !> list of points over the normalised interval [-1 .. 1].
      38             :       !> Coordinates of actual point where Green's functions were evaluated
      39             :       !> can be obtained by using an appropriate rescale_nodes_*() subroutine
      40             :       !> from the module 'negf_integr_utils'.
      41             :       REAL(kind=dp), ALLOCATABLE, DIMENSION(:)           :: tnodes
      42             :    END TYPE green_functions_cache_type
      43             : 
      44             : CONTAINS
      45             : ! **************************************************************************************************
      46             : !> \brief Reallocate storage so it can handle extra 'nnodes_extra' items for each contact.
      47             : !> \param cache        storage to expand
      48             : !> \param ncontacts    number of contacts
      49             : !> \param nnodes_extra number of items to add
      50             : !> \author Sergey Chulkov
      51             : ! **************************************************************************************************
      52         612 :    SUBROUTINE green_functions_cache_expand(cache, ncontacts, nnodes_extra)
      53             :       TYPE(green_functions_cache_type), INTENT(inout)    :: cache
      54             :       INTEGER, INTENT(in)                                :: ncontacts, nnodes_extra
      55             : 
      56             :       INTEGER                                            :: nentries_exist
      57             :       LOGICAL                                            :: is_alloc
      58         612 :       TYPE(cp_cfm_type), ALLOCATABLE, DIMENSION(:, :)    :: g_surf_contacts
      59             : 
      60         612 :       is_alloc = ALLOCATED(cache%g_surf_contacts)
      61             : 
      62         612 :       IF (is_alloc) THEN
      63         164 :          CPASSERT(SIZE(cache%g_surf_contacts, 1) == ncontacts)
      64         164 :          nentries_exist = SIZE(cache%g_surf_contacts, 2)
      65             : 
      66             :       ELSE
      67             :          nentries_exist = 0
      68             :       END IF
      69             : 
      70       45858 :       ALLOCATE (g_surf_contacts(ncontacts, nentries_exist + nnodes_extra))
      71             : 
      72         612 :       IF (is_alloc) THEN
      73       23744 :          g_surf_contacts(1:ncontacts, 1:nentries_exist) = cache%g_surf_contacts(1:ncontacts, 1:nentries_exist)
      74         164 :          DEALLOCATE (cache%g_surf_contacts)
      75             :       END IF
      76             : 
      77         612 :       CALL MOVE_ALLOC(g_surf_contacts, cache%g_surf_contacts)
      78         612 :    END SUBROUTINE green_functions_cache_expand
      79             : 
      80             : ! **************************************************************************************************
      81             : !> \brief Sort cached items in ascending order.
      82             : !> \param cache        storage to reorder
      83             : !> \param tnodes       coordinate of items in storage
      84             : !> \author Sergey Chulkov
      85             : ! **************************************************************************************************
      86          72 :    SUBROUTINE green_functions_cache_reorder(cache, tnodes)
      87             :       TYPE(green_functions_cache_type), INTENT(inout)    :: cache
      88             :       REAL(kind=dp), DIMENSION(:), INTENT(in)            :: tnodes
      89             : 
      90             :       INTEGER                                            :: ind_new, ind_old, ncontacts, nnodes
      91          72 :       INTEGER, ALLOCATABLE, DIMENSION(:)                 :: indices
      92          72 :       TYPE(cp_cfm_type), ALLOCATABLE, DIMENSION(:, :)    :: g_surf_contacts
      93             : 
      94          72 :       nnodes = SIZE(tnodes)
      95             : 
      96          72 :       CPASSERT(ALLOCATED(cache%g_surf_contacts))
      97          72 :       CPASSERT(SIZE(cache%g_surf_contacts, 2) == nnodes)
      98             : 
      99          72 :       ncontacts = SIZE(cache%g_surf_contacts, 1)
     100             : 
     101          72 :       IF (ALLOCATED(cache%tnodes)) DEALLOCATE (cache%tnodes)
     102             : 
     103       11976 :       ALLOCATE (g_surf_contacts(ncontacts, nnodes))
     104         216 :       ALLOCATE (cache%tnodes(nnodes))
     105         216 :       ALLOCATE (indices(nnodes))
     106             : 
     107        3968 :       cache%tnodes(:) = tnodes(:)
     108          72 :       CALL sort(cache%tnodes, nnodes, indices)
     109             : 
     110        3968 :       DO ind_new = 1, nnodes
     111        3896 :          ind_old = indices(ind_new)
     112       11760 :          g_surf_contacts(1:ncontacts, ind_new) = cache%g_surf_contacts(1:ncontacts, ind_old)
     113             :       END DO
     114             : 
     115          72 :       CALL MOVE_ALLOC(g_surf_contacts, cache%g_surf_contacts)
     116          72 :    END SUBROUTINE green_functions_cache_reorder
     117             : 
     118             : ! **************************************************************************************************
     119             : !> \brief Release storage.
     120             : !> \param cache        storage to release
     121             : !> \author Sergey Chulkov
     122             : ! **************************************************************************************************
     123         452 :    SUBROUTINE green_functions_cache_release(cache)
     124             :       TYPE(green_functions_cache_type), INTENT(inout)    :: cache
     125             : 
     126             :       INTEGER                                            :: icontact, ipoint, ncontacts
     127             : 
     128         452 :       IF (ALLOCATED(cache%tnodes)) DEALLOCATE (cache%tnodes)
     129             : 
     130         452 :       IF (ALLOCATED(cache%g_surf_contacts)) THEN
     131         448 :          ncontacts = SIZE(cache%g_surf_contacts, 1)
     132        7058 :          DO ipoint = SIZE(cache%g_surf_contacts, 2), 1, -1
     133       20278 :             DO icontact = ncontacts, 1, -1
     134       19830 :                CALL cp_cfm_release(cache%g_surf_contacts(icontact, ipoint))
     135             :             END DO
     136             :          END DO
     137             : 
     138         448 :          DEALLOCATE (cache%g_surf_contacts)
     139             :       END IF
     140         452 :    END SUBROUTINE green_functions_cache_release
     141           0 : END MODULE negf_green_cache
     142             :