Nodes of different colours represent the following:
Solid arrows point from a submodule to the (sub)module which it is descended from. Dashed arrows point from a module or program unit to modules which it uses.
subroutine putnode(igrid,ipe) use mod_forest implicit none integer, intent(in) :: igrid, ipe igrid_inuse(igrid,ipe)=.false. end subroutine putnode