function SIR=Sir(S,E,W,SN,SOI)
%%%%%%%%%%%%%%%%%%%%%%%%%
%  S=Direction Vector
%  E=energy
%  W=weight vector
%  SN=signal number
%  SOI=signal of interested
%  the function used in computing signal to noise and jammer with
%  the first element is signal element
%%%%%%%%%%%%%%%%%%%%%%%%
totalj=0;
totals=0;
signal=zeros(SOI,1);
jammer=zeros(SN-SOI,1);
for ii=1:SOI
    signal(ii)=abs(W'*S(:,ii))^2*E(ii);
    totals=totals+signal(ii);
end

for ii=1:SN-SOI;
    jammer(ii)=abs(W'*S(:,ii+SOI))^2*E(ii+SOI);
    totalj=totalj+jammer(ii);
end
SIR=totals/(totalj);
% SINR=10*log10(totals/(totalj+abs(W'*W)));