Plotting MATLAB values in two different colors

Question

Anyway, I wish to plot two column vectors, filled with random numbers with no negative values in them, on a 2D plot(x and y).

The 'x-vector' I can leave as it is, but with the 'y vector', I wish to plot that any y values that is equal to zero as a different color(Say red) to the other positive non-zero values(Say blue).

Please try to keep solution relatively simple, if possible, as I myself am relatively new to MATLAB as well as to this site.

Answer 1

I'm not sure what you mean by 2D plot but I assuming you mean just a normal curve. Try this:

x = rand(10, 1);
y = rand(10, 1);

y([5 8]) = 0; %Force a couple of values to be 0 for visualisation

t = 1:10;    

plot(t, x);
hold on
plot(t, y, 'g');
ind = y == 0; %Make a logical index that masks all the value where y is not 0
plot(t(ind), y(ind), 'r*');