NewtonianForceECI:

Path: SC/Environs

% Computes the Newtonian force in ECI coordinates.
 The body is represented as unit outward normals and corresponding
 areas.
--------------------------------------------------------------------------
   Form:
   f = NewtonianForceECI( qECIToBody, nBody, a, uECI, rho )
--------------------------------------------------------------------------

   ------
   Inputs
   ------
   qECIToBody      (4,:)	Quaternion from ECI to Body      
   nBody           (3,n)	Normals in the body frame
   a               (1,n)   Corresponding areas (m^2)
   uECI            (3,:)   Velocity vector (km/s)
   rho             (1,:)   Atmospheric density (kg/m^3)

   -------
   Outputs
   -------
   force           (3,:)	Force (N)

--------------------------------------------------------------------------