samer@1: % this is weird but it works
samer@1: % nan means variable, so max(nan,x)=x
samer@1: % inf means failure so max(inf,x)=inf
samer@1: function z=unify(x,y)
samer@1: 	if ~isfinite(x) || ~isfinite(y), z=max(x,y);
samer@1: 	elseif x==y, z=x; 
samer@1: 	else z=inf; 
samer@1: 	end
samer@1: end