Hills2ECI:

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   Given the reference state in ECI, converts a Hills frame state to ECI.

   Since version 7.
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   Form:
   x1 = Hills2ECI( x0, xH )
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   ------
   Inputs
   ------
   x0              (6,1) [r;v] ECI frame
   xH              (6,n) [r;v] Hills frame

   -------
   Outputs
   -------
   x1              (6,n) [r; v] ECI frame

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Children:

FormationFlying: Coord/GetHillsMats
Math: Linear/Dot
Math: Linear/Mag