DUnit:

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   Derivative of the unit vector for r.

   Since version 2.
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   Form:
   u = DUnit( r, v )
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   ------
   Inputs
   ------
   r             (3,:)   Vectors
   v             (3,:)   Vector derivatives

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   Outputs
   -------
   u             (3,:)   Unit vector derivatives

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Children:

Math: Linear/Dot
Math: Linear/Mag
Math: Linear/SXV