! 
! P_LOAD.GREG	Load an image in variable &1 
! 
! 	The image is defined by variable 'NAME' and 'TYPE' 
!	Extrema are computed if needed 
! 
on error "RETURN BASE" 
define integer new$date 
define logical change 
sic\compute new$date date 'name'.'type' 
let change new$date.ne.&1$date 
sic\if (.not.change) then 
  let change change.or.name.ne.&1$name 
  let change change.or.type.ne.&1$type 
sic\endif 
sic\if (change) then 
  say "Changing to new (or updated) file " 'name'.'type' 
  if (exist(&1)) then 
    delete /variable &1 
  endif 
  define header &1 'name'.'type' read /global 
  if (&1%extrema.eq.0) then 
    delete /var &1 
    run extrema pr:greg/extrema.init /nowindow 
  else 
    delete /var &1 
  endif 
  define image &1 'name'.'type' read /global 
  let &1$date new$date 
  let &1$name 'name' 
  let &1$type 'type' 
endif 
delete /variable new$date 
symbol drawn &1%