Question

Why aren’t these plotting the same graph?

plot([10 20 30 40 50 60],[10 20 30 40 50 60].*(1-exp(-2*[10 20 30 40 50 60]*tau)));

hold on;
plot(10,10*(1-exp(-2*10*tau)));
plot(20,20*(1-exp(-2*20*tau)));
plot(30,30*(1-exp(-2*30*tau)));
plot(40,40*(1-exp(-2*40*tau)));
plot(50,50*(1-exp(-2*50*tau)));
plot(60,60*(1-exp(-2*60*tau)));
hold off;

The first plot line works but the hold on/ hold off for the 2nd part just shows up blank in the figure.

Answer 1

The figure is not blank, rather very small points are plotted.

Try

plot(10,10*(1-exp(-2*10*tau)),'o');
plot(20,20*(1-exp(-2*20*tau)),'o');
   ...

to see a magnified version of your original plot

The closest way I can think to obtain the same plot as in your original case is by introducing one segment at a time, i.e. you have to introduce couple of points such as

 plot([10 20],[10*(1-exp(-2*10*tau)),20*(1-exp(-2*20*tau))]);
    .... and so on

Of course this goes just for a learning purpose.