Remember, we don't do a one-to-one correlation, because p x and p y are some linear combination of the m plus 1 and m minus 1 orbital.
记住,我们不需要把它们一一对应,因为px和py轨道是,m等于正负1轨道的线性组合。
But he said the energy of an X-Y bond is going to be equal to the square root.
但他说XY键的键能,会等于XX键与YY键键能乘积的平方根。
If it's in polar form I passed in a radius and angle and I'll compute what the x- and y- value is.
以及半径和角度,但是现在是这样的,不管我是以哪种形式。
So, it's the x-y plane, you can see there's no electron density anywhere there.
它在xy平面,你们可以看到在这里没有电子密度。
He still incurred -C because he ran and he also has a cost of |x-y| because he doesn't like Mr. Y winning.
他同样有-C的收益因为他参加了竞选,且他还有|x-y|的成本,因为他不喜欢Y先生获胜
Then, I gave you one other very important example of a particle moving in the x-y plane.
下面我再拿一个重要的例子,质点在 x-y 平面内的运动
If x is high relative to x-bar--this is positive-- then y tends to be low relative to its mean y-bar and this is negative.
如果x比x均值要大,这个为正,而y比y均值小,这个为负
y-- >> It adds, like, x to y -- >> David: Okay, good.
>,它会做加法,像x加-,>>,大卫:嗯,好的。
OK, as I said, I want equality in the case of points to be, are the x- and y- coordinates the same?
好,正如我所说,我想要这个例子中的,点相等的意思是?
I was expecting to compare x- and y- values, not radius and angle.
噢,发生了什么?,好吧有错误了。
I said both the x- and y- coordinates are bigger, then I'm going to return something to it.
我说过如果x和y坐标,都是更大的。
Well you know what a point is, it's got an x- and a y- coordinate, it's natural to think about those two things as belonging as a single entity.
把这两个坐标认为,是属于一个独立的实体,是理所当然的事情,因此实现这个目的的。
Right now it's a simple template, but it's a template for creating what a class looks like, and I now have an x- and y- value associated with each instance of this.
那么大家明白了为什么,我说类是一个模板了,对不对?,现在它只是一个简单的模板,但是它是一个用来-,创建形成一个类的模板。
So this first little piece of code right here says, ok you give me 2 points, I'll create another 1 of these lists and I'll simply take the x, sorry I shouldn't say x, I'm going to assume it's the x, the x-values are the two points, add them together, just right there, the y-values, add them together and return that list.
好,为了来认识到这一点,让我们来看一个简单的小例子,在你们的课堂手册上,你可以看到我写了一个小程序,它假设我得到了,这些点中的一些,我想对它们做一些操作,例如我想把它们加到一起,那么这里的第一小片,代码的意思是,好给我两个点,我会再创建一个数组。
It says, if I want to print out something I built in Cartesian form up here, says, again, I'm going to pass it in a pointer to the instance, that self thing, and then I'm going to return a string that I combine together with an open self and close paren, a comma in the middle, and getting the x-value and the y-value and converting them into strings before I put the whole thing together.
这不仅仅是个列表,它是怎么来做的?,流程是:如果我想要返回,一些已经在笛卡尔模式下建好的值,好,再说一遍,我首先要传入一个,指向实例的指针,也就是,然后我会返回一个,由开括号,闭括号,中间的一个逗号,以及提前转换为字符串格式的。
So I don't know don't, John, I would argue if I'd written this better, I would have had a method that returned the x- and the y- value, and it would be cleaner to go after it that way.
我会去辩论这么写是不是更好,我也可以写一个,返回x坐标和y坐标的方法,这么做可能会更清楚一点,这是很棒的缩写,好。
And what we see here is now when we're combining the p, we have our 2 p x and our 2 p y orbitals that are lower in energy, and then our pi anti-bonding orbitals that are higher in energy.
这里我们看到,当我们结合p轨道时,在低能处我们有,2px和2py轨道,π反键轨道在更高的能级处。
Our picture now is going to be some particle that's traveling in the x-y plane.
我们现在的情景是在 x-y 平面内,运动的质点
And similarly, actually, if we're looking at our polar coordinates here, what we see is it's any place where theta is equal to is what's going to put up on the x-y plane.
类似的,如果我们,看这里的极坐标系,我们能看到只要在theta等于,多少的地方就是xy平面。
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。
It's easy to think of a point as just a list of an x- and a y- coordinate.
或者说有两个元素的数组,把一个点认为是含有x坐标。
I take the difference in the x-values, squared, the difference in the y-values, squared, add them up, take the square root of that.
好,是毕达哥拉斯定力对不对?,求x坐标的差,然后平方,求y坐标的差,然后平方,把它们加起来,开平方。
You go back to the same x-y plane; here is some vector A.
回到刚才的 x-y 平面上,这是某个矢量 A
And that's the following. Let's take a particle that is moving in the x-y plane, so that at one instance-- sorry, let me change this graph-- is here--oh, this is bad.
接下来,我们来看一个物体,在 x-y 平面内运动,在这个例子中,对不起,我要重画一下这个图,在这里,这画得不好
For example, suppose you use vertical motion and you use y instead of x; and a would be g or -g; that's a particle falling down under the affect of gravity.
例如,假设在竖直运动中,你用 y 来代替 x,那么 a 就是 g 或者 -g,这就是一个受重力作用下落的质点
For the simplest context in which one can motivate a vector and also motivate the rules for dealing with vectors, is when you look at real space, the coordinates x and y.
对于最简单的情况,我们能用矢量,以及相关的规则来处理的,是实空间,x-y 坐标系
We know it's going around in a circle because if I find the length of this vector, which is the x-square part, plus the y-square part, I just get r square at all times, because sine square plus cosine square is one.
我们之所以知道它做圆周运动,是因为我求出了这个矢量的模长,也就是 x 的平方加上 y 的平方,我就得到了它在任意时刻的模长平方,因为正弦平方加余弦平方始终等于1
So we're talking about an experiment when you generate-- Each experiment generates both an x and a y observation and we know when x is high, y also tends to be high, or whether it's the other way around.
这里说的是由试验产生的,每一次试验可以获得一组x与y的观察值,当x值大的时候,y值可能也大,或者相反
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