ShortArcToHills:

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   Convert short arc measurements to an approximate Hill's state.
   Calls fminsearch on PinholeCamera to find an approximate Hills state.

   Type ShortArcToHills for a demo. The demo calls PinholeCamera to
   compute pixel locations.

   Since version 11.
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   Form:
   x = ShortArcToHills( p, t, n, qHToBody, e )
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   ------
   Inputs
   ------
   p         (2,n) Pixel locations - at least 3
   t         (1,n) Times (sec)
   n         (1,1) Orbit rate of observing spacecraft (rad/s)
   qHToBody  (4,1) Quaternion from Hills to Body
   e         (1,1) Camera data structure
                   .f            (1,1) Focal length (mm)
                   .w            (1,1) Pixel width (micro-m)
                   .bodyToCamera (3,3) Transformation from body to camera
   xECI      (6,1) ECI state of imager

   -------
   Outputs
   -------
   x         (6,1) Initial Hills state [r;v]

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Children:

Common: Database/Constant
Common: Quaternion/AU2Q
Common: Quaternion/QForm
FormationFlying: Coord/GetHillsMats
FormationFlying: Dynamics/HillsEqns
FormationFlying: Transformation/Hills2ECI
Imaging: Optics/PinholeCamera
Math: Linear/Mag
Math: Linear/Unit
OrbitMiniToolbox: Support/El2RV