Only process the latest data and throw away old data. You need to consider streaming processing of your data. See suggestions below in the code.
n = ceil(app.daqDevice.Rate/10);
%signal = [];
% Pre-allocate memory space for fixed amount of data
% This will make program faster
signal = zeros(nmax, 1); % nmax number of samples
% For data logging, consider fopen and fwrite for speed.
% start measurement
start(app.daqDevice,"continuous")
pause(0.1)
while(1)
% check measurement end condition
if app.Button_2.Value == 1
stop(app.daqDevice)
app.Button.Value = 0;
% save data block by block not in one-go
save(fullfile(app.SaveFolderPath,...
str2double(app.TrialNumber_Value.Text)+...
"_"+app.SpeedList.Value+".mat"),...
'signal')
return;
end
% read data form DataAquisition Obj
data = read(app.daqDevice,n);
% save data here using fwrite
% update measured value
signal(1:nmax-n) = singal(n+1:nmax); % shift data
signal(nmax-n+1:nmax) = data; % attach new data
%signal(nmax ) = [signal; data];
% update time plot
% plot the buffered signal instead of all signal
plot(app.Timeplot, data.Time, data.Variables)
ylim(app.Timeplot,[-1,1])
% compute spectrum on buffered data signal below
% update spectrum plot
[pxx,f] = pwelch(data.Variables,512,256,1024,32000);
plot(app.PSDplot,f, 10*log10(pxx))
end
