npts = 100
clat = new(npts,float)
clon = new(npts,float)
nggcog (40.,-105,7.0,clat,clon)

print(clat)
print(clon)

wks = gsn_open_wks("png","nggcog_ncl")

res = True
res@gsnMaximize        = True
res@xyLineColor        = "navyblue"
res@xyLineThicknessF   = 3.0
res@trYMinF            = 32
res@trYMaxF            = 48
res@trXMinF            = -116
res@trXMaxF            = -95
res@tiMainString       = "NCL version of nggcog"

;---Draw great circle as an XY plot
plot = gsn_csm_xy(wks,clon,clat,res)

;---Draw a map
mpres              = True
mpres@gsnMaximize  = True
mpres@gsnFrame     = False
mpres@mpLimitMode  = "LatLon"
mpres@mpMinLatF    = 20
mpres@mpMaxLatF    = 60
mpres@mpMinLonF    = -120
mpres@mpMaxLonF    = -70
mpres@mpFillOn     = False
mpres@tiMainString = "NCL version of nggcog"
mpres@pmTickMarkDisplayMode = "Always" ; nicer tickmarks
map = gsn_csm_map(wks,mpres)

;---Draw the markers
mkres = True
mkres@gsMarkerIndex = 16
gsn_polymarker(wks,map,clon,clat,mkres)

;---Advance the frame
frame(wks)