Swallowtail Catastrophe
A Catastrophe which can occur for three control factors and one behavior axis. The equations
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display such a catastrophe (von Seggern 1993, Nordstrand). The above surface uses
and 
.
References
Nordstrand, T. ``Swallowtail.'' http://www.uib.no/people/nfytn/stltxt.htm. von Seggern, D. CRC Standard Curves and Surfaces. Boca Raton, FL: CRC Press, p. 94, 1993.
- Universal Graph
- Universal Statement
- Universal Turing Machine
- Unknot
- Unknotting Number
- Unless
- Unlesss
- Unmixed
- Unpoke Move
- Unsafe
- Unsolved Problem
- Unstable Improper Node
- Unstable Node
- Unstable Spiral Point
- Unstable Star
- Untouchable Number
- U-Number
- Upper Bound
- Upper Integral
- Upper Limit
- Upper Sum
- Upper-Trimmed Subsequence
- Upward Drawing
- Urchin
- Utility Graph