Jog,
I am not sure what it is that you are asking for. The result of the simulation will be stored in usr_ans if you run the simulation with usr_ans = sim(...) as you mentioned in your question. This is still true when the simulation is stoped with the stop block. You can view the variable by typing the variable name, or you can plot it with plot(usr_ans).
Since you mentioned scripts it might be the case that you are using a MathScript function (.msf) or command (.msc) in which case the variables are local to the function or command. To return the variable it would have to be one of the values that are returned to by the function. You would need to modify the script to enable it to return the value that you are interested in.
Carl L.
National Instruments
