function [y_dst] = conv_decode_metric(s, output, y_src)
% Compute the accumulated Hamming distance for the current symbol s
% .. relative to the current output value.
% Each metric value y is associated with the destination vertex of an edge.
% .. The metric value is a function of the symbol value s for the transition
% .. represented by the edge_array column, 
% .. the output value for the transition represented by that edge, 
% .. and y_src, the metric value of the edge's source vertex.
%
% D.Bozarth 03-14-08 SSU Engineering Science
%
s0 = imag(s); d0 = imag(output);
s1 = real(s); d1 = real(output);

y_dst = y_src + abs(s0 - d0) + abs(s1 - d1);
%
% end function