it is 'ylpos', not 'ylops' if you want to use secondary y-axis At 11:34 AM 10/12/2005, you wrote: >Thanks for the reply. However, I need to use 'set ylops 0 r' command to >overlap two different variables in one figure which have different scale >(one is from -100 to 0, the other from 0 0.6). How can I do that using >Grads. > >Thanks. > >Wuhu