CASE CLOSED. THANKS YOU

I have 1440 data of tidal elevation (24 hours recording every 1 minute), I attached my data (Book1.xlsx). My question is how can I do High Pass Filter with those data? My experience in this case is zero.

Answer 1

[Mathieu NOE]

hello Nabil

the code below implements low and high pass filtering

hope it helps

T = readtable('Book1.xlsx');
time = T.Var1;
y = T.Var2;

dt = 60; % seconds (data sampled every min)
Fs = 1/dt;
samples = length(y);
t = (0:samples - 1)*dt/3600; % now in hours

%%% filter data %%%
N = 20;
y_LP = smoothdata(y, 'gaussian' , N); % low pass filtered data
y_HP = y - y_LP; % high pass filtered data

%%% plot data %%%
figure(1)
subplot(211),plot(t,y,t,y_LP);legend('Raw','low pass filtered');
title(['Data samples at Fs = ' num2str(Fs) ' Hz / filtered with smoothdata' ]);
xlabel('Time (hours) ')
ylabel('Tidal depth () ')
subplot(212),plot(t,y_HP);legend('high pass filtered');
title(['Data samples at Fs = ' num2str(Fs) ' Hz / filtered with smoothdata' ]);
xlabel('Time (hours) ')
ylabel('Tidal depth () ')

[Nabil Amirul]

Thank you very much sir, I am very appreciate it

[Mathieu NOE]

My pleasure