code: def test_somenan():
      np = pytest.importorskip("numpy")
      xyz = np.stack((xyz0, (nan, nan, nan)))
  
      lat, lon, alt = pm.ecef2geodetic(xyz[:, 0], xyz[:, 1], xyz[:, 2])
      assert (lat[0], lon[0], alt[0]) == approx(lla0)
  
file_path: pymap3d/src/pymap3d/tests/test_geodetic.py
imports: from math import isnan, nan, radians, sqrt
  import pymap3d
  import pytest
  from pytest import approx
label_desc: Use image node_id 14 for calling a global function with example usage: test_somenan() without return types