Metadata
Author: LASER-wikipedia2
Data
English[en]
Intuitively, the process can be pictured as follows: first shrink the real line to the open interval (-π,π) on the x-axis; then bend the ends of this interval upwards (in positive y-direction) and move them towards each other, until you get a circle with one point (the topmost one) missing.
Chinese[zh]
直觉上,这个过程可视为:首先将实数线收缩为 x-轴上的开区间 (-π,π);然后将这个区间的两端向上(y-轴正方向)弯曲,并移动使它们靠近,直到得到一个去掉一点(最上点)的圆周。