code: def test_initialize(X):
      d = StudentT(3)
      assert d.d is None
      assert d.means is None
      assert d.covs is None
      assert d._initialized == False
      assert_raises(AttributeError, getattr, d, "_w_sum")
      assert_raises(AttributeError, getattr, d, "_xw_sum")
      assert_raises(AttributeError, getattr, d, "_xxw_sum")
  
      assert_raises(AttributeError, getattr, d, "_inv_cov")
      assert_raises(AttributeError, getattr, d, "_inv_cov_dot_mu")
      assert_raises(AttributeError, getattr, d, "_log_det")
      assert_raises(AttributeError, getattr, d, "_log_sigma_sqrt_2pi")
  
      d = StudentT(3, [1.2], None)
      assert d.d is None
      assert d.covs is None
      assert d._initialized == False
      assert_raises(AttributeError, getattr, d, "_w_sum")
      assert_raises(AttributeError, getattr, d, "_xw_sum")
      assert_raises(AttributeError, getattr, d, "_xxw_sum")
  
      assert_raises(AttributeError, getattr, d, "_inv_cov")
      assert_raises(AttributeError, getattr, d, "_inv_cov_dot_mu")
      assert_raises(AttributeError, getattr, d, "_log_det")
      assert_raises(AttributeError, getattr, d, "_log_sigma_sqrt_2pi")
  
      d = StudentT(3, None, [1.2])
      assert d.d is None
      assert d.means is None
      assert d._initialized == False
      assert_raises(AttributeError, getattr, d, "_w_sum")
      assert_raises(AttributeError, getattr, d, "_xw_sum")
      assert_raises(AttributeError, getattr, d, "_xxw_sum")
  
      assert_raises(AttributeError, getattr, d, "_inv_cov")
      assert_raises(AttributeError, getattr, d, "_inv_cov_dot_mu")
      assert_raises(AttributeError, getattr, d, "_log_det")
      assert_raises(AttributeError, getattr, d, "_log_sigma_sqrt_2pi")
  
      d._initialize(3)
      assert d._initialized == True
      assert d.means.shape[0] == 3
      assert d.d == 3
      assert_array_almost_equal(d.means, [0.0, 0.0, 0.0])
      assert_array_almost_equal(d.covs, [0.0, 0.0, 0.0])
      assert_array_almost_equal(d._w_sum, [0.0, 0.0, 0.0])
      assert_array_almost_equal(d._xw_sum, [0.0, 0.0, 0.0])
      assert_array_almost_equal(d._xw_sum, [0.0, 0.0, 0.0])
      assert_array_almost_equal(d._xxw_sum, [0.0, 0.0, 0.0])
  
      d._initialize(2)
      assert d._initialized == True
      assert d.means.shape[0] == 2
      assert d.d == 2
      assert_array_almost_equal(d.means, [0.0, 0.0])
      assert_array_almost_equal(d.covs, [0.0, 0.0])
      assert_array_almost_equal(d._w_sum, [0.0, 0.0])
      assert_array_almost_equal(d._xw_sum, [0.0, 0.0])
      assert_array_almost_equal(d._xw_sum, [0.0, 0.0])
      assert_array_almost_equal(d._xxw_sum, [0.0, 0.0])
  
      d = StudentT(3, [1.2, 9.3], [1.1, 9.2])
      assert d._initialized == True
      assert d.d == 2
  
      d._initialize(3)
      assert d._initialized == True
      assert d.means.shape[0] == 3
      assert d.d == 3
      assert_array_almost_equal(d.means, [0.0, 0.0, 0.0])
      assert_array_almost_equal(d.covs, [0.0, 0.0, 0.0])
  
      d = StudentT(3)
      d.summarize(X)
      d._initialize(4)
      assert d._initialized == True
      assert d.means.shape[0] == 4
      assert d.d == 4
      assert_array_almost_equal(d._w_sum, [0.0, 0.0, 0.0, 0.0])
      assert_array_almost_equal(d._xw_sum, [0.0, 0.0, 0.0, 0.0])
      assert_array_almost_equal(d._xw_sum, [0.0, 0.0, 0.0, 0.0])
      assert_array_almost_equal(d._xxw_sum, [0.0, 0.0, 0.0, 0.0])
  
imports: import os
  import numpy
  import torch
  import pytest
  from pomegranate.distributions import StudentT
  from ._utils import _test_initialization_raises_two_parameters
  from ._utils import _test_initialization
  from ._utils import _test_predictions
  from ._utils import _test_efd_from_summaries
  from ._utils import _test_raises
  from nose.tools import assert_raises
  from numpy.testing import assert_array_almost_equal
label_desc: Use image node_id 11 for calling a global function with example usage: test_initialize(X) without return types