;
;------------------------------------------------------------------
;
pro mapset,pos,projcen,perimlat
;
; Calls map_set for polar stereographic projection.
; (note this has to be recalled after labpol, to reestablish mapping
;  coords for trac cursor). Map_set sets !x.type=2 (mapping). The plot
;  commands in labpol set !x.type=0 or 1. Track latlon does not work
;  with !x.type ne 2, e.g., after labpol. Calling labpol before map_set 
;  would work for contours only (imcon=1), but images displayed after 
;  labpol would cover up tic marks from labpol)
;
if (projcen(0) ne -90 and projcen(0) ne 90) then begin
  map_set,projcen(0),projcen(1),/stereo,position=pos,/noborder,/noerase
endif else begin
  if (projcen(0) eq -90.) then begin
    map_set,projcen(0),projcen(1),/stereo,/noerase,$
      position=pos,/noborder,limit=[-90.,-180.,perimlat,180.]
  endif else begin
    map_set,projcen(0),projcen(1),/stereo,/noerase,$
      position=pos,/noborder,limit=[perimlat,-180.,90.,180.]
  endelse
endelse
return
end