That hands a small number of coders, tweaking the algorithms that determine who sees whom across the virtual bar, tremendous power to engineer mating outcomes.   

tweaking the algorithns......the virtual bar 这句话做状语还是定语,如果作定语，为什么有逗号。非限制性定语从句不是不可以简化成分词形式吗？如果做状语请问怎么翻译？