RadiusSphericalTorus:

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   Major and minor radii for a spherical torus.

   Type RadisuSphericalTorus for a demo.
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   Form:
   [r, a] = RadiusSphericalTorus( v, aR )
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   ------
   Inputs
   ------
   v             (1,1)  Volume
   aR            (1,1)  Aspect ratio = Major radius/minor radius

   -------
   Outputs
   -------
   r             (1,1)  Major radius
   a             (1,1)  Minor radius 

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   Reference: Szirmay, L. V., "Nuclear Fusion Reactor Design Fundamentals,
              p.137.
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