finding several values close to the set point

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Hello!
I would like to calculate the period in a curve using the mean. However, my attempts to date have not been successful, and I think there is a simple way to do it.
I put random data - eventually I will have a lot of different data and this is to be the method for determining it.
I managed to find the closest value, but unfortunately 1, and I need a few of them to determine the curve's symmetry axis.
Edit: It doesn't search for peaks, because the data on which I work has a few of them on the main peaks, and filtration changes the shape of the plot very much.
Thank you for every advice.
A=[1.5 2.3 3.7 4.6 5.3 4.2 3.8 2.7 1.3 2.6 3.9 4.8 6.1 5.3 4.3 3.6 2.8 1.6 2.4 3.6 4.7 5.4 4.0 2.8 1.5 2.7 3.8 4.7];
A=A';
s = size(A);
t = 1:1:s(1);
plot (t,A)
a = mean(A);
Edit2:
In the attachment I add the real data I work on. From each cell I choose 1 column as X and 3 columns as Y in plot (X, Y).

Accepted Answer

Ameer Hamza
Ameer Hamza on 18 Mar 2020
The following code works by detecting the peak of each cycle and then calculate the average distance between each peak
A=[1.5 2.3 3.7 4.6 5.3 4.2 3.8 2.7 1.3 2.6 3.9 4.8 6.1 5.3 4.3 3.6 2.8 1.6 2.4 3.6 4.7 5.4 4.0 2.8 1.5 2.7 3.8 4.7];
A=A';
t = 1:1:size(A,1);
plot(t,A);
[~, index_peaks] = findpeaks(A);
t_peaks = t(index_peaks);
period = mean(diff(t_peaks));
  8 Comments
Caroline
Caroline on 18 Mar 2020
Analyzing the data, I noticed that the solution has 1 drawback. Peaks occur in different places, therefore the periods are not equal :(.
Ameer Hamza
Ameer Hamza on 18 Mar 2020
Yes, that can be issue, but since you are taking the average of each interval so this difference is somewhat compensated.

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