1function [w1]=optwbm(bWin,n,w,z,beta,mu,snrThresh,amcInds)
 2
 3
 4% adapt everyone under no threshold
 5if isempty(snrThresh) 
 6    w = beta*w + mu*bWin*ones(1,size(z,2))*diag(z(n,:)) / ...
 7            norm(bWin)^2;
 8% threshold certain tracks
 9else 
10    w(:,amcInds) = beta*w(:, amcInds) + mu*bWin*...
11            ones(1,length(find(amcInds))) * diag(z(n,amcInds)) / ...
12            norm(bWin)^2;
13end
14w1=w;
15end