# Declare the Landolt UBVRI standards catalog variables catalog V 4 # the V magnitude BV 5 # the (B-V) color UB 6 # the (U-B) color VR 7 # the (V-R) color RI 8 # the (R-I) color VI 9 # the (V-I) color error(V) 12 # the V magnitude error error(BV) 13 # the (B-V) color error error(UB) 14 # the (U-B) color error error(VR) 15 # the (V-R) color error error(RI) 16 # the (R-I) color error error(VI) 17 # the (V-I) color error