Problem with plotting the sample data from tutorial with command display

[Giannakos Apostolos]

Dear list

I am new in Grads software and i encountered a problem about how you plot
data with the software.

I runed the executable file gradsc
I followed the instructions in the tutorial but i noticed that when i give
the command  >>d ps   it tells me that does Contouring: 500 to 1000
interval 50 but in the Grads window nothing is displayed.

I followed the commands and they  do not give me an error. Does anyone
knows what seems to be the problem and i can not display my data?

I used the  sample data files from the Grads tutorial model.ctl,model.grb,
model.gmp

Thanks in Advance