code: def test_glsar_iter0(self):
      endog = self.res.model.endog
      exog = self.res.model.exog
  
      rho = np.array([0.207, 0.275, 1.033])
      mod1 = GLSAR(endog, exog, rho)
      res1 = mod1.fit()
      res0 = mod1.iterative_fit(0)
      res0b = mod1.iterative_fit(1)
      # check iterative_fit(0) or iterative_fit(1) does not update rho
      assert_allclose(res0.params, res1.params, rtol=1e-11)
      assert_allclose(res0b.params, res1.params, rtol=1e-11)
      assert_allclose(res0.model.rho, rho, rtol=1e-11)
      assert_allclose(res0b.model.rho, rho, rtol=1e-11)
  
file_path: statsmodels/statsmodels/regression/tests/test_glsar_stata.py
imports: import numpy
  from numpy.testing import assert_almost_equal, assert_allclose, assert_equal
  from statsmodels.regression.linear_model import GLSAR
  from statsmodels.tools.tools import add_constant
  from statsmodels.datasets import macrodata
label_desc: Use image node_id 4 for calling the TestGLSARCorc obj's underlying member method code with example usage: obj.test_glsar_iter0() without return types