Thus, we give a make-graph method of conic section on plane with arbitrary point as foci, arbitraryline as directrices and arbitrary positive number as eccentricity.
从而给出了以平面上任意点为焦点、任意直线为准线，任意正数为离心率的圆锥曲线的直接作图方法。
2
The important thing is that the line the animation follows can be any arbitrary path.
重要的事情是，动画沿着的线路可以是任何任意的路径。
3
This approach has many problems: the file format is arbitrary, only one set of keywords is saved, objects are not even on the horizon, data values are limited to one line of text, and so on.