% function b = indep(S,gap)
% determines the first row that is dependent on the previous rows of S.
% The coefficients of dependence is returned in b
function b = indep( S,gap)

if nargin == 1
        gap = 1.0e8;
end
[rows,cols] = size(S);
ind = 1;
i = 2;
while ind & i <= rows    
      shortS = S(1:i,:);
      sigma = svd(shortS*shortS');
      len = length(sigma);
      if(sigma(len)/sigma(1) < (eps*max(i,cols)))
        ind =0;
      else
        shsig = [sigma(2:len);sigma(len)];
        if any( (sigma ./shsig) > gap)
           ind = 0;
        else
           ind = 1;
           i = i+1;
        end
      end
end
if ind
        b =[];
else
        c = S(i,:)/S(1:i-1,:);
        c = makezero(c,gap);
        b = [-c 1];
end