get_end_point

Get end point of vector defined by two points and a length.

Parameters:

        base_pt - Coordinates of initial point of vector.
       cross_pt - Coordinates of point on vector.
       length_j - Total length of vector (joint)

Returns:

  Coordiantes of the terminal point of vector that initiates at the
  base_pt, contains the cross_pt, and is of the specified length.

See Also:

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discretize_posture