pro idl_map2
  ; Define the data by reading the image into IDL,
  ; creating the daymap variable to hold the data.
  READ_JPEG, FILEPATH('Day.jpg', $
     SUBDIR=['examples','data']), daymap
   
  ; Define the latitude and longitude data for the contour.
  longitude = FINDGEN(360) - 180
  latitude = FINDGEN(180) - 90
  cntrdata = SIN(longitude/30) # COS(latitude/30)
   
  ; Display the global image.
  map2 = IMAGE(daymap, $
  LIMIT=[-90,-180,90,180], GRID_UNITS=2, $
     IMAGE_LOCATION=[-180,-90], IMAGE_DIMENSIONS=[360,180],$
     MAP_PROJECTION='Mollweide')
   
  ; Draw the contour on top of the map image.
  cntr2 = CONTOUR(cntrdata, longitude, latitude, $
     GRID_UNITS=2, N_LEVELS=10, RGB_TABLE=34, /OVERPLOT)
stop
end