code: def test_ellipse_axes():
      Y, X = np.mgrid[:1024, :1024]
      Y = Y / 1024.0
      X = X / 1024.0
      im = (2.0 * (Y - 0.5) ** 2 + (X - 0.5) ** 2) < 0.2
      maj, min = mh.features.ellipse_axes(im)
      assert np.abs(2 - (maj / min) ** 2) < 0.01
  
      maj2, min2 = mh.features.ellipse_axes(im.T)
  
      assert np.abs(maj - maj2) < 0.001
      assert np.abs(min - min2) < 0.001
  
      im = ((Y - 0.5) ** 2 + (X - 0.5) ** 2) < 0.2
      maj, min = mh.features.ellipse_axes(im)
      assert np.abs(1 - (maj / min) ** 2) < 0.01
  
file_path: mahotas/mahotas/tests/test_features_shape.py
imports: import mahotas.features.shape
  import numpy
  import mahotas
  from mahotas.features.shape import roundness, eccentricity
label_desc: Use image node_id 4 for calling a global function with example usage: test_ellipse_axes() without return types