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Suppose f of x, y, z equals k1, that is my equation, s1 and it gives me a solution s1.
假设我的方程是这样，然后给出了一个解。
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For example, F x y z if I have an equation that looks like this, f of x, y, z.
打个比方，我有个这样的方程。
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It was awkward teaching an introduction Y and probably for that reason while I was teaching Lit 300, which was then called Lit Y, Z Paul de Man was teaching Lit Z.
教入门课非常尴尬,也许正因为这样，我教文学300时，当时它还叫文学，保罗，德，曼教教文学。
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X Y Z It's more interestingly named an X or Y or Z.
你也可以把它命名为。
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That's it. Again, these other p dxy dyz - or the d x y, d y z, those are going to be those more complicated linear combinations, you don't need to worry about them.
同样，这些p轨道,或者，它们是一些,很复杂的线性组合，你们，不用管它。
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This now has, gee, a funny thing, x it says IF x is less than y AND x is less than z, then do something.
代码现在有，啊，一个有趣的东西，代码先是判断x是不是小于y并且,是不是小于z，然后做一些事情。
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XYZ I might as well do it as x, y, z because we are talking about something that is going in three space.
我最好设成,因为我们在讨论,三维的事物。
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x y z And I have another equation f of x, y, z.
若我有另一个方程。
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And just as with variables, you should use some common sense, some style here, and the function's name should X Y communicate what it does, calling it X or Y or Z is generally not all that helpful.
就像变量，你使用一些常识，一些类型，和函数名需要,传达它所做的事情，把它叫做,或者Z通常是没有什么用处的。
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So, you can see, it's much easier to describe that as one term, r here, instead of using both y and z.
所以，你们可以看到，用r而不是y和z来做描述，使得它变得更为简单。
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Um-hmm. So, it's going to be the y z nodal plane, or in other words, we can say it's any place where phi is equal to 90 degrees.
嗯，是ｙｚ平面，换句话说，是在phi等于９０度的面。
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And now we get the p orbitals, remember we want to fill up 1 orbital at a time before we double up, so we'll put one in the 2 p x, then one in the 2 p z, and then one in the 2 p y.
我们到了p轨道，记住在双倍填充之前,我们想要每次填充至一个轨道，所以我们在2px填充一个然后2pz填充一个，然后2py填充一个。
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So you can see if you take phi, and you move it over 90 degrees, we're right here in the y z plane.
你们可以看到，把phi转到９０度，它就是ｙｚ面。
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So, we can have the 2 p x, 2 p y, and 2 p z orbitals.
所以我们有2个px2个py2个pz轨道。
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Z So it would be incorrect to try to assign this to a variable X or Y or Z, because it doesn't actually give me anything back.
这个是错误的，来赋值这个给变量X或Y或,因为它的确没有返回什么给我。
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It adds x to y and stores it into z. But if someone wants to be a even a little more snarky, what does this program do?
它把x加上y，再把结果存到z中，但是如果有人,想要做的有点不合常理点呢，那这个程序会做什么？
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Now, unlike high school math or in algebra Z where you call things X and Y and Z, in programming, in computer science, you're actually dealing with humans where it's useful to have a variable name that's more descriptive than X and Y and Z.
不像高中数学或者代数中,称为X和Y和，在程序设计和计算机科学里，你实际上是在和人打交道,在这里有个描述性比xyz更强的,变量名称是很重要的。
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All right, so one thing that I want to point out, which I said many, many times on Friday, and this is perhaps the last time I'll say it, but one last time is we can think about why we only see a line for the 2 p orbital, versus we don't see separate lines for a 2 p x, a 2 p y, and a 2 p z.
好的，我还要指出一个问题，这个问题我在上周五已经说了很多很多次了，这可能是我最后一次提到它，但是这最后一次让我们来考虑一下,为什么我们只看到了一条，对应于，2，p，轨道的线,而不是分别对应于，2，p，x，2，p，y，2，p，z，的线？
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