Plot Superquadratic Surfaces

This is a pair of functions for plotting general superellipsoids and supertoroids

Much like SPHERE(), ELLIPSOID(), or SUPERQUAD(), these functions calculate and return the matrices required to plot a general superellipsoid or supertoroid using MESH() or SURF().
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Unlike SUPERQUAD(), SUPERELLIPSOID() calculates the general form
with fully independent axis orders. i.e.:
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((X-Cx) / Rx)^Px + ((Y-Cy) / Ry)^Py + ((Z-Cz) / Rz)^Pz = 1
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For convenience, both functions accept parameters as vectors or as scalars with implicit expansion.
As with the built-in functions, the number of points can be set.
The default value for N is 50.
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If no outputs are specified, a new surf plot will be created.
Display axes can be specified if the first argument is an axes handle.
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A demo file is included (demo file uses subplot_tight from the FEX)