Compute a unit vector from cone and clock angles.

   The cone angle is the angle between the force and sun vectors and the clock 
   angle is in the sun normal plane measured from the Y axis of the reference
   frame. The X axis is along the sun line s; this may be towards or away from the
   sun depending on user preference. The remaining axes are defined by the 
   cross product of X with either the orbit normal or the velocity vector.

   u = cos(cone)*x + sin(cone)*cos(clock)*y + sin(cone)*sin(clock)*z

   Requires the position, velocity and sun vectors. The latter is a unit
   vector. You can input multiple sets and the function will return
   a 3-by-n vector.

   Type ConeClockToU for a demo showing the unit vectors for a circular
   orbit around the sun. See also QSail which uses the same frame.

   Since version 7.
   [u,qItoCC] = ConeClockToU( cone, clock, r, v, s, c )
   [u,qItoCC] = ConeClockToU( cone, clock, q )

   cone          (1,:)  Cone angle (rad)
   clock         (1,:)  Clock angle (rad)
   r             (3,:)  Orbit vector
   v             (3,:)  Velocity vector
   s             (3,:)  Sun unit vector
   c             (1,1)  Sign convention, optional

   u             (3,n) Unit vectors
   qItoCC        (4,n) Quaternions from inertial frame to cone/clock frame



Common: Database/Constant
Common: Graphics/Plot3D
Common: Quaternion/Mat2Q
Common: Quaternion/QTForm
Common: Transform/Eul2Mat
Math: Linear/Cross
Math: Linear/Mag
Math: Linear/Unit
SC: BasicOrbit/RVFromKepler