The online ability to run scripts seems to be broken.
I used MATLAB Online to devise this —
% LD = load('data.mat')
file = websave('data.mat','https://www.mathworks.com/matlabcentral/answers/uploaded_files/1809778/data.mat');
LD = load(file);
data = LD.data;
x = linspace(0, 5.5, numel(data)); % Supply Missing Coordinate
Fs = 1/x(2)
[FTs1,Fv] = FFT1(data,x);
figure
plot(Fv, abs(FTs1)*2)
xlim([0 3])
title('Fourier Transform (Informs Filter Design)')
data_filt = highpass(data, 0.0425, Fs, ImpulseResponse='iir');
[pksf,locsf] = findpeaks(data_filt);
[pks,locs] = findpeaks(data);
locs = [locsf(1) locs]
pks = data(locs)
figure
plot(x, data)
hold on
plot(x(locs), data(locs), 'rv' )
hold off
figure
plot(x, data_filt)
title('Filtered ‘data’')
function [FTs1,Fv] = FFT1(s,t)
% Arguments:
% s: Signal Vector Or Matrix
% t: Associated Time Vector
t = t(:);
L = numel(t);
if size(s,2) == L
s = s.';
end
Fs = 1/mean(diff(t));
Fn = Fs/2;
NFFT = 2^nextpow2(L);
FTs = fft((s - mean(s)) .* hann(L).*ones(1,size(s,2)), NFFT)/sum(hann(L));
Fv = Fs*(0:(NFFT/2))/NFFT;
% Fv = linspace(0, 1, NFFT/2+1)*Fn;
Iv = 1:numel(Fv);
Fv = Fv(:);
FTs1 = FTs(Iv,:);
end
.
