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!! Module neighborLists |
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!! Impliments verlet neighbor lists for force modules. |
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!! Automagically expands neighbor list if size too small |
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!! up to maxAllocations times. If after maxAllocations we try to |
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!! expand the neighbor list, we get an error message and quit. |
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!! @author Charles F. Vardeman II |
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!! @author Matthew Meineke |
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!! @author J. Daniel Gezelter |
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!! @version $Id: neighborLists.F90,v 1.4 2003-03-13 17:45:54 gezelter Exp $, |
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|
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module neighborLists |
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|
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use definitions |
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#ifdef IS_MPI |
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use mpiSimulation |
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#endif |
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|
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implicit none |
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PRIVATE |
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|
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!--------------MODULE VARIABLES----------------------> |
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!! Parameter for size > # of long range particles neighbor list |
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!! should be. |
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integer, parameter :: listMultiplier = 80 |
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!! Maximum number of times we should reallocate neighbor list. |
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integer, parameter :: maxAllocations = 5 |
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!! Number of times we have allocated the neighbor list. |
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integer, save :: nAllocations = 0 |
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!! Pointer array to location in list for atom i. |
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integer, dimension(:),public, pointer :: point => null() |
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!! Neighbor list for atom i. |
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integer, dimension(:),public, pointer :: list => null() |
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!! Position array of previous positions for check. Allocated first time |
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!! into saveNeighborList. |
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real( kind = dp ), dimension(:,:), allocatable , save :: q0 |
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!! Current list size |
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integer, save :: listSize |
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!--------------MODULE ACCESS--------------------------> |
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public :: expandNeighborList |
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public :: checkNeighborList |
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public :: saveNeighborList |
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public :: getNeighborListSize |
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|
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contains |
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|
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|
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subroutine expandNeighborList(natoms, error) |
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integer, intent(out) :: error |
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integer :: natoms |
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integer :: alloc_error |
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integer :: oldSize = 0 |
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integer :: newSize = 0 |
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integer :: i |
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integer, dimension(:), pointer :: newList => null() |
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error = 0 |
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|
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|
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!! First time through we should allocate point and list. |
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!! If one is associated and one is not, something is wrong |
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!! and return a error. |
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#ifndef IS_MPI !!/Non MPI |
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if (.not. associated(point) .and. & |
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.not. associated(list) ) then |
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allocate(point(natoms),stat=alloc_error) |
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if (alloc_error /= 0) then |
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error = -1 |
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return |
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end if |
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allocate(list(listMultiplier * natoms),stat=alloc_error) |
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if (alloc_error /= 0) then |
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error = -1 |
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return |
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end if |
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nAllocations = nAllocations + 1 |
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else |
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error = -1 |
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return |
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end if |
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#else !!// MPI |
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if (.not. associated(point) .and. & |
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.not. associated(list) ) then |
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allocate(point(getNRow(plan_row)),stat=alloc_error) |
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if (alloc_error /= 0) then |
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error = -1 |
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return |
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end if |
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allocate(list(listMultiplier * getNCol(plan_col)),stat=alloc_error) |
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if (alloc_error /= 0) then |
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error = -1 |
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return |
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end if |
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nAllocations = nAllocations + 1 |
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return |
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else |
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error = -1 |
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return |
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end if |
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#endif !! //MPI |
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|
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! Expand the neighbor list |
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|
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! Check to see if we have exceeded the maximum number of allocations. |
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if (nAllocations > maxAllocations) then |
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error = -1 |
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return |
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else !! Expand the list. |
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oldSize = size(list) |
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|
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#ifndef IS_MPI !!Not MPI |
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newSize = listMultiplier * natoms + oldSize |
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allocate(newList(newSize), stat=alloc_error) |
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if (alloc_error /= 0) then |
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error = -1 |
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return |
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end if |
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#else !! IS_MPI |
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newSize = listMultiplier * getNCol(plan_col) + oldSize |
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allocate(newList(newSize), stat = alloc_error) |
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if (alloc_error /= 0) then |
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error = -1 |
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return |
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end if |
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#endif !! IS_MPI |
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!! Copy old list to new list |
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do i = 1, oldSize |
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newList(i) = list(i) |
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end do |
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!! Free old list |
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deallocate(list,stat=alloc_error) |
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if (alloc_error /= 0) then |
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error = -1 |
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return |
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end if |
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|
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!! Point list at new list |
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list => newList |
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end if |
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|
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listSize = size(list) |
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end subroutine expandNeighborList |
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|
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!! checks to see if any long range particle has moved |
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!! through the neighbor list skin thickness. |
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subroutine checkNeighborList(natoms, q, rcut, rlist, update_nlist) |
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integer :: natoms |
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real(kind = dp), intent(in) :: rcut, rlist |
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real( kind = dp ), dimension(:,:) :: q |
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integer :: i |
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real( kind = DP ) :: dispmx |
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logical, intent(out) :: update_nlist |
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real( kind = DP ) :: dispmx_tmp |
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real( kind = dp ) :: skin_thickness |
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integer :: nlocal |
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|
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nlocal = natoms |
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skin_thickness = rlist - rcut |
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dispmx = 0.0E0_DP |
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!! calculate the largest displacement of any atom in any direction |
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|
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|
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|
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#ifdef MPI |
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|
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!! If we have changed the particle idents, then we need to update |
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if (.not. allocated(q0) .or. & |
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size(q0) /= nlocal) then |
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update_nlist = .true. |
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return |
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end if |
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|
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dispmx_tmp = 0.0E0_DP |
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do i = 1, nlocal |
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dispmx_tmp = max( abs ( q(1,i) - q0(1,i) ), dispmx ) |
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dispmx_tmp = max( abs ( q(2,i) - q0(2,i) ), dispmx ) |
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dispmx_tmp = max( abs ( q(3,i) - q0(3,i) ), dispmx ) |
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end do |
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call mpi_allreduce(dispmx_tmp,dispmx,1,mpi_double_precision, & |
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mpi_max,mpi_comm_world,mpi_err) |
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#else |
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|
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do i = 1, nlocal |
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dispmx = max( abs ( q(1,i) - q0(1,i) ), dispmx ) |
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dispmx = max( abs ( q(2,i) - q0(2,i) ), dispmx ) |
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dispmx = max( abs ( q(3,i) - q0(3,i) ), dispmx ) |
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end do |
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#endif |
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|
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!! a conservative test of list skin crossings |
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dispmx = 2.0E0_DP * sqrt (3.0E0_DP * dispmx * dispmx) |
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|
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update_nlist = (dispmx.gt.(skin_thickness)) |
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|
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end subroutine checkNeighborList |
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|
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|
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!! Saves neighbor list for comparison in check. |
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!! Save_neighborList will work even if the number of |
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!! local atoms has changed. |
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subroutine saveNeighborList(q) |
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real(kind = dp ), dimension(:,:), intent(in) :: q |
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integer :: list_size |
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|
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!! get size of list |
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list_size = size(q) |
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|
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if (.not. allocated(q0)) then |
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allocate(q0(3,list_size)) |
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else if( list_size > size(q0)) then |
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deallocate(q0) |
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allocate(q0(3,list_size)) |
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endif |
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q0 = q |
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end subroutine saveNeighborList |
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|
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|
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function getNeighborListSize() result(returnListSize) |
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integer :: returnListSize |
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returnListSize = listSize |
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end function getNeighborListSize |
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|
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end module neighborLists |