How to compute frequency and amplitude from a text file?

So far, i have used this code to plot the text file:

[fid,msg] = fopen('Rose.txt','rt');

assert(fid>=3,msg)

C = textscan(fid, '%f%f', 'CommentStyle','#', 'CollectOutput',true);

fclose(fid);

M = C{1};

After this i wish to calculate frequency and amplitude for a duration of 5 seconds at different intervals. Can someone please help me out with the code in order to do so? Thanks in advance :)

[Bob Thompson]

What are you trying to calculate the frequency and amplitude of, exactly? Does the text file contain numeric time data?

[Akshat Shrivastava]

The text file has 2 columns (Time and electrical activity of respiration). The values of text file are float type. I want to calculate the average frequency and amplitude for a duration of 5 seconds at different intervals.

[Bob Thompson]

Ok, so C then is a 2 column matrix with that data. Check out this article:

https://www.mathworks.com/matlabcentral/answers/46500-how-do-i-get-amplitude-and-frequency-from-a-wave-signal

[Akshat Shrivastava]

Hi, I want to tell you that the plot that i get of my text file is not a sine or a cos waveform. Also, i do not know my sampling frequency. Would that link still be useful?`

[Bob Thompson]

Does your data have some kind of time based oscillation? If so then you can use an FFT tool. As for sampling frequency, there should be some way of finding out, but you can always just pick something and get relative results based on the frequency you picked.

Yes, the link is still useful.