Plotting problem - plot only appears after script is run twice.

[John Bingham]

Hi! Can anyone help me. I have loaded 3-6-4 but when I try and plot a scatter graph with a script I get a blank figure, if I rerun the script the scatter plot appears ok.

 

I am using vista

 

the script is as follows:

 

t=[0:.1:100]';

u=-1+0.02*t;

y=sin(0.2*t);

plot(t,y,t,u)

%y (y-axis) is plotted against t (x-axis)

%and u (y-axis) is plotted against t (x-axis).

 

Most grateful for your help

 

John