I have a signal and have marked and plot any points that exceed a power threshold. How can I create a new array of the data points that exceed the threshold? The distance between each point is differs slightly so I can't just write x:y:z
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The distance between each point is differs slightly so I can't just write x:y:z. I need to just take exactly the points above the threshold and put them into an array.
The array is from over_x(1):over_x(end), but I don't know how to include all the points in between.
Thanks in advance
2 Comments
dpb
on 19 Jun 2017
If over_x is the array of points
over_x=x(x>threshold);
then you've already got it.
The expression over_x(1):over_x(end) is shorthand for over_x(1):over_x(length(over_x)) and is equivalent to just writing over_x without any subscript expression.
Not sure what the issue is, precisely??? Can you explain more of what the difficulty is you're having?
Answers (1)
Jan
on 19 Jun 2017
Edited: Jan
on 19 Jun 2017
You forgot to mention, how your data are available. If I guess this detail, it might differ from your setup and confuse you. But I try it:
t = sort(rand(1, 1000)); % The non-uniform x values
y = bsxfun(@plus, rand(1, 1000), linspace(0, 2, 1000));
figure;
subplot(1,2,1);
plot(t, y);
Now get all values above a limit:
index = (y > 2);
subplot(1,2,2);
plot(t(index), y(index));
Or perhaps you want to get all values from the first value above the limit to the last one? The question is not clear in this point.
index = find(y > 2);
plot(t(index(1):index(end)), y(index(1):index(end)));
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