Base drift removal of ecg

Code vb.net - [expand]
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clear;
system('rdsamp -r e0801 -f 17.3 -l 10.0 -p > e0801.txt');  % jump 17.3 seconds, read 10 seconds
[t,y(:,1),y(:,2)] = textread('e0801.txt','%f %f %f');      % read time and voltages from file
fs = 1 / (t(2) - t(1));                 % sample rate, hertz
period = 0.96;                          % cardiac period, seconds
N = length(y);
t = (0 : N-1) / fs;
for n = 1:2                             % for each voltage waveform
  subplot(4,1,n*2-1); plot(t,y(:,n)); xlim([0 max(t)]);
  title('Input Data','FontWeight','bold'); xlabel('Seconds'); ylabel('Millivolts');
  xlim1 = xlim;  ylim1 = ylim;          % remember plot limits
  %
  % Subtract baseline drift. See [url]https://www.dataq.com/applicat/articles/an14.htm[/url]
  z(:,n) = y(:,n) - smooth(y(:,n),round(fs*period));
  subplot(4,1,n*2-0); plot(t,z(:,n)); xlim([0 max(t)]);
  title('Subtract Baseline Drift','FontWeight','bold'); xlabel('Seconds'); ylabel('Millivolts');
  xlim(xlim1);
end;