# how to draw a figure eight curve using tikz? [closed]

Just as the title, how to draw a figure eight curve using tikz ? Or more general, how to use tikz to draw a parametric curve with the given parametrization ? I knew how to draw basic things by tikz like straight lines, vector, the curves using \draw .. controls or \draw to[in=, out=], and the parametric curves is something new to me. Thanks

• I do not really understand, what you are asking (maybe because my English is not good enough). What do you mean with “figure eight curve”? An octagon (eight-sided figure)? Or something like this but with 8 instead of 9 points? Can you show, what you've tried? Commented Mar 28 at 8:58
• I think you should spend some time here, which you can use to express x(t) and y(t) by parameter t etc. ... tikz.dev/dv Commented Mar 28 at 8:59
• @cabohah a figure-eight curve is a curve with the shape of the number eight, in math we usually call it "figure-eight curve", just like in the answer below. Commented Mar 28 at 9:56
• You might Google Lissajous figure, also called Bowditch Curve. Commented Mar 29 at 1:59

Here's something:

\documentclass{article}

\usepackage{tikz}

\begin{document}

\begin{tikzpicture}
% Figure Eight Curve
\draw[domain   = 0:360,
samples  = 200,
variable = \t,
smooth, blue, thick]
plot ({2*cos(\t)},{2*sin(2*\t)});
\end{tikzpicture}

\end{document}


Which generates this:

Hope this is useful. Next time, please consider trying something out and showing where you failed rather than a bare-bones question.

• Thank you really much. this really helpful to me. Commented Mar 28 at 10:04