extract points from line plot

I have a line plot and I tried to extract points from the line using YData=get(get(gca,'children'),'YData');, how do I set the number of points that I extracted?

Answer 1

[Walter Roberson]

You cannot set the number of points. You will extract all of them using that code. After you have extracted them all, you can throw some of them away.

If you wanted to restrict the number of objects (e.g., lineseries objects) that you extracted data from, then you could use

MaxObj = 17;  %for example
ch = get(gca, 'Children');
if length(ch) > MaxObj; ch(MaxObj+1:end) = []; end
YData = get(ch, 'YData');

This would not be the same as limiting the number of points, because each line or lineseries object might have a different number of points.