begin npts = 100 lat = random_uniform( 25, 50,(/2,npts/)) ; Create some dummy lat/lon data lon = random_uniform(235,290,(/2,npts/)) ; containing the position of ; the 2 sets of markers. wks = gsn_open_wks("png","poly2f") ; Open "poly2f.png" file mpres = True ; Map resources desired. mpres@gsnFrame = False ; Don't advance the frame mpres@mpMinLatF = 25 ; Zoom in on United States. mpres@mpMaxLatF = 50 mpres@mpMinLonF = 235 mpres@mpMaxLonF = 290 ; default ocean land inland water mpres@mpFillColors = (/"background","LightBlue","PaleGreen","LightBlue"/) map = gsn_csm_map(wks,mpres) ; Call gsn_csm_map to draw a map. mkres = True ; Plot options for markers. mkres@gsMarkerSizeF = .01 ; Default is 0.007 mkres@gsMarkerIndex = 16 ; Use filled dots for 1st set of markers. mkres@gsMarkerColor = "Brown" ; Color for 1st set of markers gsn_polymarker(wks,map,lon(0,:),lat(0,:),mkres) mkres@gsMarkerSizeF = .01 mkres@gsMarkerIndex = 13 ; Use stars for 2nd set of markers. mkres@gsMarkerColor = "Blue" ; Color for 2nd set of markers gsn_polymarker(wks,map,lon(1,:),lat(1,:),mkres) mkres@gsMarkerSizeF = .02 ; Marker size and thickness mkres@gsMarkerThicknessF = 2 ; for NDC markers. mkres@gsMarkerIndex = 16 mkres@gsMarkerColor = "Brown" gsn_polymarker_ndc(wks,0.1,0.2,mkres) mkres@gsMarkerIndex = 13 mkres@gsMarkerColor = "Blue" gsn_polymarker_ndc(wks,0.65,0.2,mkres) txres = True ; Plot options for text strings. txres@txFontHeightF = 0.03 ; Text font height txres@txJust = "CenterLeft" ; Text justification point gsn_text_ndc(wks,"brown markers",0.13,0.2,txres) gsn_text_ndc(wks,"blue markers",0.68,0.2,txres) frame(wks) end