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   Outputs the set of acceptable measurements. The last 3 inputs
   are only needed for chordwidth measurements. 
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   Form:
   k = Outliers( z, ra, dec, bias, type, range, u1, u2, er, cant, erbias )
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   ------
   Inputs
   ------
   z                      Measurement vector
   ra                     Right ascension
   dec                    Declination
   bias                   Sensor bias
   type                   Measurement type [1=ssa,2=chordwidth,3=dihedral]
   range                  Allowable range
   u1                     Vector [us if ssa or dihedral, ue if chordwidth]
   u2                     Vector ue if dihedral angle
   er                     Earth radii
   cant                   Cant angle
   erbias                 Earth radius bias

   -------
   Outputs
   -------
   k                      Set of acceptable measurements

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