How to plot contour lines showing 95% confidence interval on surface plot?

Hi,
I am usng cwt to perform wavelet transform on my data. I am using surface command to plot the wavelet power (example is in Fig. 1 or top figure). I want to plot contour lines on this plot to show the region of wavelet power within 95% confidence interval.
I need suggestion on:
  1. How to calculate 95% confidence interval of wavelet power? The cwt returns a matrix of wavelet power which is a n-by-m array of complex numbers. n is the length of frequency vector and m is the length of time vector.
  2. How to plot a contour or line on the surface plot which will show the area that is within this 95% confidence interval? Example of what I need is in Fig. 2 or bottom figure. The white lines are the contours. I have drawn them manually here to show an example.
Thanks in advance.

2 Comments

Try this trick
% A and B your matrices you comparing
C = A - B;
C1 = (C-min(C(:)))/(max(C(:))-min(C(:)));
contour(X,Y,C1,[.95 .95])
I am not comparing any data. I only have one matrix, which consists of wavelet coeeficients.
I tried it without C = A-B; it did not help.

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Answers (1)

it'll automatically show the 95% confidence interval, so it shoud be:
wt( your time series data)
you can also use wtc(v1,v2) to show the coupling btw two variables.
Nisreen

Asked:

on 30 Apr 2020

Answered:

on 16 Sep 2020

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