code: def example_cv_nonoise():
      x1 = [0.6, 0.48, 0.64]
      x2 = [-0.8, 0.48, 0.36]
      x3 = [0.48, 0.64, -0.6]
      x = np.random.randn(30, 3) * 0.1
      x[0::3] += x1
      x[1::3] += x2
      x[2::3] += x3
      x = (x.T / np.sqrt(np.sum(x**2, 1))).T
  
      precision = 50.0
      sub = np.repeat(np.arange(10), 3)
      vmm = select_vmm_cv(
          list(range(1, 8)),
          precision,
          x,
          cv_index=sub,
          null_class=False,
          ninit=20,
      )
      vmm.show(x)
  
      # check that it sums to 1
      s, area = sphere_density(100)
      return vmm
  
imports: from warnings import warn
  import numpy
label_desc: Use image node_id 6 for calling a global function with example usage: example_cv_nonoise() and returns: vmm