Convert ECEF into geocentric coordinates
    
    Parameters
    ----------
    x : float or array_like
        ECEF-X in km
    y : float or array_like
        ECEF-Y in km
    z : float or array_like
        ECEF-Z in km
    ref_height : float or array_like
        Reference radius used for calculating height.
        Defaults to average radius of 6371 km
    Returns
    -------
    latitude, longitude, altitude
        numpy arrays of locations in degrees, degrees, and km

def ecef_to_geocentric(x, y, z, ref_height=None):
    """Convert ECEF into geocentric coordinates
    
    Parameters
    ----------
    x : float or array_like
        ECEF-X in km
    y : float or array_like
        ECEF-Y in km
    z : float or array_like
        ECEF-Z in km
    ref_height : float or array_like
        Reference radius used for calculating height.
        Defaults to average radius of 6371 km
    Returns
    -------
    latitude, longitude, altitude
        numpy arrays of locations in degrees, degrees, and km
        
    """
    if ref_height is None:
        ref_height = earth_geo_radius

    r = np.sqrt(x ** 2 + y ** 2 + z ** 2)
    colatitude = np.rad2deg(np.arccos(z / r))
    longitude = np.rad2deg(np.arctan2(y, x))
    latitude = 90. - colatitude

    return latitude, longitude, r - ref_height