mirror of https://gitlab.com/QEF/q-e.git
57 lines
1.7 KiB
Fortran
57 lines
1.7 KiB
Fortran
!
|
|
! Copyright (C) 2001 PWSCF group
|
|
! This file is distributed under the terms of the
|
|
! GNU General Public License. See the file `License'
|
|
! in the root directory of the present distribution,
|
|
! or http://www.gnu.org/copyleft/gpl.txt .
|
|
!
|
|
!-----------------------------------------------------------------------
|
|
subroutine wsinit(rws,nrwsx,nrws,atw)
|
|
!-----------------------------------------------------------------------
|
|
!
|
|
USE kinds, only : DP
|
|
implicit none
|
|
integer i, ii, ir, jr, kr, nrws, nrwsx, nx
|
|
real(DP) rt, eps, rws(0:3,nrwsx), atw(3,3)
|
|
parameter (eps=1.0d-6,nx=2)
|
|
ii = 1
|
|
do ir=-nx,nx
|
|
do jr=-nx,nx
|
|
do kr=-nx,nx
|
|
do i=1,3
|
|
rws(i,ii) = atw(i,1)*ir + atw(i,2)*jr + atw(i,3)*kr
|
|
end do
|
|
rws(0,ii)=rws(1,ii)*rws(1,ii)+rws(2,ii)*rws(2,ii)+ &
|
|
rws(3,ii)*rws(3,ii)
|
|
rws(0,ii)=0.5d0*rws(0,ii)
|
|
if (rws(0,ii).gt.eps) ii = ii + 1
|
|
if (ii.gt.nrwsx) call errore('wsinit', 'ii.gt.nrwsx',1)
|
|
end do
|
|
end do
|
|
end do
|
|
nrws = ii - 1
|
|
return
|
|
end subroutine wsinit
|
|
!
|
|
!-----------------------------------------------------------------------
|
|
function wsweight(r,rws,nrws)
|
|
!-----------------------------------------------------------------------
|
|
!
|
|
USE kinds, only : dp
|
|
implicit none
|
|
integer ir, nreq, nrws
|
|
real(DP) r(3), rrt, ck, eps, rws(0:3,nrws), wsweight
|
|
parameter (eps=1.0d-6)
|
|
!
|
|
wsweight = 0.d0
|
|
nreq = 1
|
|
do ir =1,nrws
|
|
rrt = r(1)*rws(1,ir) + r(2)*rws(2,ir) + r(3)*rws(3,ir)
|
|
ck = rrt-rws(0,ir)
|
|
if ( ck .gt. eps ) return
|
|
if ( abs(ck) .lt. eps ) nreq = nreq + 1
|
|
end do
|
|
wsweight = 1.d0/DBLE(nreq)
|
|
return
|
|
end function wsweight
|