convert_cartesian_to_spherical
                        Converts Cartesian to Spherical Coordinates.
convert_spherical_to_cartesian
                        Converts Spherical to Cartesian Coordinates.
cross_validate_concentration
                        Cross-validates The Concentration Parameter In
                        A 3D Spherical Regression.
expm                    Computes the Exponential of a 3D Skew Symmetric
                        Matrix.
fit_regression          Fits a 3D Spherical Regression.
get_equally_spaced_points
                        Generates Equally Spaced Points On A 3D Sphere.
get_skew_symmetric_matrix
                        Gets a 3-by-3 Skew Symmetric Matrix.
logm                    Computes the Logarithm of a 3D Rotation Matrix.
nprotreg                nprotreg: Nonparametric Rotations for
                        Sphere-Sphere Regression.
simulate_regression     Simulates a 3D Spherical Regression.
simulate_rigid_regression
                        Simulates a Rigid 3D Spherical Regression.
weight_explanatory_points
                        Weights the Specified Explanatory Points in a
                        3D Spherical Regression.
