get_cell_index Subroutine

  subroutine get_cell_index(xp,ipe,igrid,ixc1,ixc2,ixc3)
    ! for given point (xp), provide the corrsponding processor (ipe), 
    ! grid number (igrid) and cell index (ixc^D)

    double precision :: xp(1:ndim)
    integer :: ipe,igrid,ixc1,ixc2,ixc3

    double precision :: x3d(1:3)
    double precision :: dxb1,dxb2,dxb3,xbmin1,xbmin2,xbmin3,xbmax1,xbmax2,&
       xbmax3
    integer :: indomain,ixOmin1,ixOmin2,ixOmin3,ixOmax1,ixOmax2,ixOmax3,j
    integer :: datas(1:ndim+2)

    indomain=0
    if (xp(3)>=xprobmin3 .and. xp(3)<xprobmax3) indomain=indomain+1
    if (xp(2)>=xprobmin2 .and. xp(2)<xprobmax2) indomain=indomain+1
    if (xp(1)>=xprobmin1 .and. xp(1)<xprobmax1) indomain=indomain+1

    if (indomain==ndim) then
      ! find pe and igrid
      x3d=0.d0
      do j=1,ndim
        x3d(j)=xp(j)
      enddo
      call find_particle_ipe(x3d,igrid,ipe)

      if (mype==ipe) then
        ! looking for the cell index
        xbmin1=rnode(rpxmin1_,igrid)
        xbmin2=rnode(rpxmin2_,igrid)
        xbmin3=rnode(rpxmin3_,igrid)
        xbmax1=rnode(rpxmax1_,igrid)
        xbmax2=rnode(rpxmax2_,igrid)
        xbmax3=rnode(rpxmax3_,igrid)
        dxb1=rnode(rpdx1_,igrid)
        dxb2=rnode(rpdx2_,igrid)
        dxb3=rnode(rpdx3_,igrid)
        ixOmin1=ixmlo1
        ixOmin2=ixmlo2
        ixOmin3=ixmlo3
        ixc1=floor((xp(1)-xbmin1)/dxb1)+ixOmin1
        ixc2=floor((xp(2)-xbmin2)/dxb2)+ixOmin2
        ixc3=floor((xp(3)-xbmin3)/dxb3)+ixOmin3
        datas(1)=ixc1
        datas(2)=ixc2
        datas(3)=ixc3
        datas(ndim+1)=ipe
        datas(ndim+2)=igrid
      endif

      call MPI_BCAST(datas,ndim+2,MPI_INTEGER,ipe,icomm,ierrmpi)
    endif

    ixc1=datas(1)
    ixc2=datas(2)
    ixc3=datas(3)
    ipe=datas(ndim+1)
    igrid=datas(ndim+2)

  end subroutine get_cell_index