And shielding is a little bit of a misnomer because it's not actually that's the electron's blocking the charge from another electron, it's more like you're canceling out a positive attractive force with a negative repulsive force.

屏蔽有一点点用词不当,因为它事实上不是,电子阻挡了来自另一个电子的电荷,它更像你在用一个负排斥力，抵消一个正吸引力,但是屏蔽是考虑这个问题,的很好的方式。

麻省理工公开课 - 化学原理课程节选

And that's a wonderful thing to have because it gives you that modularity, that encapsulation that basically says, when I create a point, the only way I can get at the values, is by using one of the defined methods, in this case it could be Cartesian, Cartesian and get all the pieces of that.

这是很棒的一件事情,因为它让你有了，模块性以及封装性，这基本上也就是说，当我创建了一个点，我能够得到它的值的唯一的方式，就是用一个定义好的方法，在这个例子中也就是。

麻省理工公开课 - 计算机科学及编程导论课程节选