星形线

星形线（）或稱為四尖瓣線（），是一個有四個尖點的內擺線，也屬於超橢圓的一種。所有星形线皆可以依以下的方程式比例縮放而得
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外部連結
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• [http://www-history.mcs.st-andrews.ac.uk/history/Curves/Astroid.html "Astroid" at The MacTutor History of Mathematics archive]
• [http://www.mathcurve.com/courbes2d/astroid/astroid.shtml "Astroïde" at Encyclopédie des Formes Mathématiques Remarquables] (in French)
• [https://web.archive.org/web/20170824133613/http://www.2dcurves.com/roulette/roulettea.html Article on 2dcurves.com]
• [http://xahlee.org/SpecialPlaneCurves_dir/Astroid_dir/astroid.html Visual Dictionary Of Special Plane Curves, Xah Lee]
• [http://demonstrations.wolfram.com/BarsOfAnAstroid/ Bars of an Astroid] by Sándor Kabai, The Wolfram Demonstrations Project.

六次曲線

Asteroida (geometria)