Wow, OK, maybe not so wow, but this is now constant. This is constant time access. So I can do searching in constant time which is great.
喔,当然,可能没那么,但是现在是常数级了,这是常数时间的访问。
This doesn't work. Can I meet you in some other time?
如果您觉得这个时间不方便,我能在其他时间见约你吗?”。
And the reason is, and this will come up on the problems and a lot of students end up using this equation, which is why I want to head it off and mention it ahead of time, we can't use an equation because this equation is very specific for light.
原因是,很多同学在解题时,都会用这个方程,所以我要,事先提醒你们一下,我们不能用这个方程,因为它只对光是用。
And my real answer is, go try it out, because obviously you can tell I frequently do this the wrong way and the TAs give me a hard time every time. John.
你可以,而我真正的答案是去试一试吧,因为很明显你可以发现我老是做错,而我的助教总是给我难堪,约翰。
And I think our time is about up, so we'll listen to this and you can go out as we hear the fourth statement of this.
我想我们的时间快要结束了,我们一边听就可以一边走了,我们听到的是第四次表达
D-A-V-I-D Well, if I've got a five-letter word like D-A-V-I-D, well, that's like five bytes and yet we only have the ability thus far in this class to return one thing at a time I can't return five bytes to you, but wait a minute, those bytes by nature of a computer are just stored in RAM.
好的,如果有5个字母的单词,如,那是5个字节,我们只能返回一个东西,而不能返回5个字节,等一下,这些字节被计算机本能地,存储在内存中。
First of all, I'm very pleased when this happens, because I'm pretty confident that I can do this under duress, but I may not do it right every time.
首先,我非常乐意你们指出我的错误,因为虽然我对这些公式了如指掌,但我并不能保证每次都写对
Just a few reminders, if any of you are here for the first time, and I know there are a few, if you go to this particular website, and you can get to this from the classes server as well, you'll see the course website that we've developed and it has a lot more information than if you just go to the classes server and click on the syllabus.
提醒一句,如果有同学是第一次来听课,我看到了有些新面孔,你们可以登录这个网站,从课程服务器也能找到,你们会发现我们更新了课程网站,其中含有大量的信息,若你只访问课程服务器,点击教程大纲
Now this isn't the first time in this course that I've paused over a moment at a crossroads where you can't possibly take both paths but where it is obviously very, very difficult to make up one's mind.
现在是这个课程中第一次,在一个分叉路口停下,我们不可能同时走两条路,但是这也显然是非常难以决定的一个地方。
I can't help thinking this is a complete waste of time.
我忍不住在想,这完全是在浪费时间。
And again, this points out something I wanted to me-- I mentioned last time, list can be heterogeneous, in the sense that the elements can be multiple different types.
这儿又指出了一点我想要告诉大家的,我上节课也提到了,就是数组是多相的,也就是说元素可以是多种类型的。
It's just some random chunk of four bytes that happens to be available at this point in time, but I can put something there.
只是一些随机的四字节的内存块,在这里是可以使用的,但是我可以在那里放置东西。
I can just whip out a variable, this time it's gonna be dynamically stored there.
我们可以临时分配一个变量,将这个值暂时存放在这个变量中。
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?
Yeah, if my machine will come back up, there we go. So, I'm going to now go ahead and write a little piece of code, and I put it here and I hope you can actually see these better this time, let me uncomment that region.
让我们写出代码来吧,好,如果我的电脑能回来的话,好了,那么,我要去写一小块代码,我把它放在这里以期望大家这次,能看的更清楚点。
应用推荐