code: def ecef2nedv(
      x, y, z, lat0, lon0, deg: bool = True
  ) -> tuple[float, float, float]:
      """
      for VECTOR between two points
  
      Parameters
      ----------
      x : float
          ECEF x coordinate (meters)
      y : float
          ECEF y coordinate (meters)
      z : float
          ECEF z coordinate (meters)
      lat0 : float
          Observer geodetic latitude
      lon0 : float
          Observer geodetic longitude
      deg : bool, optional
            degrees input/output  (False: radians in/out)
  
      Results
      -------
  
      (Vector)
  
      n : float
          North NED coordinate (meters)
      e : float
          East NED coordinate (meters)
      d : float
          Down NED coordinate (meters)
      """
      e, n, u = ecef2enuv(x, y, z, lat0, lon0, deg=deg)
  
      return n, e, -u
  
file_path: pymap3d/src/pymap3d/ned.py
imports: from __future__ import annotations
  from .ecef import ecef2enu, ecef2enuv, ecef2geodetic, enu2ecef
  from .ellipsoid import Ellipsoid
  from .enu import aer2enu, enu2aer, geodetic2enu
label_desc: Use image node_id 7 for calling a global function with example usage: ecef2nedv(x, y, z, lat0, lon0, deg) and returns: n,  e,  unknown