How to neatly exclude values from a plot?

I'm plotting 2 functions: eta, feta. What I want to do is plot feta for values between 0, 0.5, 0.7, 0.8, 0.95 and exclude the rest.

I tried somethig like this:

plot(eta(eta<0.5 | eta>0.7), feta(eta<0.5 | eta>0.7), 'k') 

but it hasn't worked. Any ideas?

Answer 1

[Image Analyst]

"What I want to do is plot feta for values between 0, 0.5, 0.7, 0.8, 0.95 and exclude the rest. "

So that means you want feta between 0 and 0.95 and nowhere else. So do this:

indexes = (feta > 0) & (feta < 0.95);
plot(eta(indexes), feta(indexes), 'k-', 'LineWidth', 2);
grid on;

[HC98]

ok great! Is there a way I can set values outside this range to nan so they aren't plotted and the lines don't join?? So basically it only plots eta when indexes = true

[Dyuman Joshi]

"Is there a way I can set values outside this range to nan"

Yes, use the indices to assign.

Image Analyst has already shown you how to get the indices, you can utilize that to assign the values.

[Image Analyst]

What I showed you is how to plot only within the range. If you want to plot the whole range but have NaNs where you don't want to plot, you can do that too:

indexes = (feta > 0) & (feta < 0.95);
eta(indexes) = nan;
feta(indexes) = nan;
plot(eta, feta, 'k-', 'LineWidth', 2);
grid on;

Elements that are nan will not plot a marker (if you're using one) at the nan location, and will not have lines (if you're using them) connecting the nan point to adjacent non-nan points.

Not sure what the x axis limits will be in that case, so you might want to use xlim.