a question about example

[machunpo]

is:issue is:open How do I plot a vertical line such as x=2? You can currently do this by creating a Parametric equation with x=2 and y=s, and setting s to an interval that covers your viewing window. See this for an example. the link 'See this for an example' is 失效了

[senventise]

Parametric equation (参数方程), like this.