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module force_utilities |
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use definitions, ONLY : DP |
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use parameter |
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use simulation, ONLY : q,q0,natoms,use_pbc,box,nlocal |
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use status, ONLY: error,info |
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#ifdef MPI |
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use mpi_module |
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#endif |
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implicit none |
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PRIVATE |
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|
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public :: check |
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public :: save_nlist |
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public :: wrap |
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|
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contains |
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|
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subroutine check(update_nlist) |
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|
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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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|
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dispmx = 0.0E0_DP |
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|
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!! calculate the largest displacement of any atom in any direction |
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|
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#ifdef MPI |
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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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do i = 1, natoms |
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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 check |
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|
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subroutine save_nlist() |
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integer :: i |
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#ifdef MPI |
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do i = 1, nlocal |
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#else |
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do i = 1, natoms |
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#endif |
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q0(1,i) = q(1,i) |
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q0(2,i) = q(2,i) |
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q0(3,i) = q(3,i) |
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end do |
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|
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end subroutine save_nlist |
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|
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function wrap(r,dim) result(this_wrap) |
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|
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|
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real( kind = DP ) :: r |
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real( kind = DP ) :: this_wrap |
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integer :: dim |
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|
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if (use_pbc) then |
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! this_wrap = r - box(dim)*dsign(1.0E0_DP,r)*int(abs(r/box(dim)) + 0.5E0_DP) |
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this_wrap = r - box(dim)*nint(r/box(dim)) |
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else |
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this_wrap = r |
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endif |
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|
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return |
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end function wrap |
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|
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|
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end module force_utilities |
