参数的过程中使用的一种求导法则。 具体来说，链式法则是将复合函数的导数表示为各个子函数导数的连乘积的一种方法。在This can be done as A part of an official patch or bug deal with. For open up-source software, for example Linux, a backport is often furnished by a 3rd party and then submitted to the