anchor.diff:    real(dp), intent(in)     :: x,y
     real(dp)                 :: psi
   
  -  psi = half*(x*x+y*y)
  +  psi = half*(x*x+y*y+x*y)
   
     end function psifunc
   
  
positive.code: 
  else
  
  endif
  
  
  
  call stop_error(0,'Ok')
  
  
negative.code: dy = 0.01
  ofile = 'streamline.nc'
  
  ! ... Lineargs
  ! ...
  call lineargs_ini(na)
  if (na.eq.0) call help_write()
  
  call argflg('--h',hlp)
  call argflg('-help',hlp)
  if (hlp) then
    call help_write()
  else
    call header()
  endif
  
  call argstr('-o',out,ofile)
  call argflg('-A',agrid)
  call argflg('-C',cgrid)
  call argdbl('-dx',fdx,dx)
  