Detecting and Quantifying T-Wave Alternans: The PhysioNet/Computing in Cardiology Challenge 2008 1.0.0

File: <base>/sources/Simoliuniene/TWA_spektras.m (457 bytes) 
[m,n]=size(Koeficientai);
w = kaiser(m);
TWAcriteria=0;
for j=1:4
    Koef(:,1)=Koeficientai(:,j)-mean(Koeficientai(:,j),1);
    spektras(:,j)=periodogram(Koef(:,1),w,257);
    SpSum=sum(spektras(:,j),1);
    critt(i,j)=spektras(129,j)/SpSum;
    critc(i,j)=critt(i,j)/(mean(spektras(102:110,j))/SpSum);
    if critc(i,j)>1.9
        TWAcriteria=TWAcriteria+critt(i,j)^2;
    end;
end;
Answer='TWA criteria is:'
TWAcriteria=sqrt(TWAcriteria)