How to plot scales versus time in continuous wavelet transform?

Dear all, I have data set over time. I used continuous wavelet transform as follows:

C = cwt (signal,1:200,'bior3.3','plot')

How can I plot the scales against time (instead of scales against the number of data)?

Sincerely.

Answer 1

[albara]

To plot the Continuous Wavelet Transform (CWT) coefficients with scales against time instead of the number of data points, you can create a time vector that corresponds to your signal and use it on the x-axis of your plot. Here's an example:

% Example signal (Replace this with your actual data)
signal = randn(1, 1000);
% Sampling frequency (Replace this with the correct value for your data)
fs = 1000;
% Calculate the time vector
N = length(signal);
t = (0:N-1) / fs;
% Compute the CWT coefficients
scales = 1:200;
wname = 'bior3.3';
C = cwt(signal, scales, wname);
% Create a meshgrid for the time and scales
[T, S] = meshgrid(t, scales);
% Plot the CWT coefficients with time and scales
figure;
surf(T, S, abs(C), 'EdgeColor', 'none');
view(0, 90); % Set the view to 2D
xlabel('Time (s)');
ylabel('Scale');
title('Continuous Wavelet Transform (CWT) Coefficients');
colorbar;

This code should generate a 2D plot of the CWT coefficients with the correct time and scale axes based on your signal and sampling frequency.

Important: There may be some mistakes in this answer Experts can tell if there are any mistakes

[Navid]

Hello,

I am reporting an issue I faced while using the Morse wavelet. I received an error message stating, "Error when using surf. Data dimensions must agree." I would appreciate your assistance in resolving this problem and any guidance you can offer. Thank you for your time and attention to this matter.

Best regards,

Navid