compute_local_frame_on_sphere

compute_local_frame_on_sphere(p_ptg_radec, deg=False)

Return base of tangent local frame of unit sphere for a given direction with astronomer orientation convention

Parameters:

• p_ptg_radec (numpy array float) – array ra, dec
• deg (boolean) – input angle in degree, else rad

Returns:

unit vectors of tangential frame in sphere

Return type:

tuple of 3 numpy array 3D