Soft-Margin 2-norm Bias Calculator

function [ bias ] = GetSoftBiasDos( weights, kernel, labels, C)
[xm xn] = size(kernel);
counter = 0;
bias = 0;

for i = 1:xm
    if weights(i) > (10^-10)  %calculate first <w xi>
        sgnLastY = labels(i) > 0;
        partialSum = 0;
        for j = 1:xm
            partialSum = partialSum + labels(j) * kernel(i,j) * weights(j);
        end
       
        %reset partial sum
        wXi = partialSum;
        partialSum = 0;
       
        for j = i:xm
            if weights(i) > (10^-10) && sgnLastY ~= (labels(j) > 0)
              for j = 1:xm
                 partialSum = partialSum + labels(j) * kernel(i,j) * weights(j);
              end
             
              %save second <w xj>
              wXj = partialSum;
              bias = bias + -(wXi + wXj) / 2 - (labels(i) * weights(i) - labels(j) * weights(j)) / (2 * C);
              counter = counter + 1;
            end
        end
    end
end

bias = bias / counter;