code: def test_pade_4term_exp():
      # First four Taylor coefficients of exp(x).
      # Unlike poly1d, the first array element is the zero-order term.
      an = [1.0, 1.0, 0.5, 1.0 / 6]
  
      nump, denomp = pade(an, 0)
      assert_array_almost_equal(nump.c, [1.0 / 6, 0.5, 1.0, 1.0])
      assert_array_almost_equal(denomp.c, [1.0])
  
      nump, denomp = pade(an, 1)
      assert_array_almost_equal(nump.c, [1.0 / 6, 2.0 / 3, 1.0])
      assert_array_almost_equal(denomp.c, [-1.0 / 3, 1.0])
  
      nump, denomp = pade(an, 2)
      assert_array_almost_equal(nump.c, [1.0 / 3, 1.0])
      assert_array_almost_equal(denomp.c, [1.0 / 6, -2.0 / 3, 1.0])
  
      nump, denomp = pade(an, 3)
      assert_array_almost_equal(nump.c, [1.0])
      assert_array_almost_equal(denomp.c, [-1.0 / 6, 0.5, -1.0, 1.0])
  
      # Testing inclusion of optional parameter
      nump, denomp = pade(an, 0, 3)
      assert_array_almost_equal(nump.c, [1.0 / 6, 0.5, 1.0, 1.0])
      assert_array_almost_equal(denomp.c, [1.0])
  
      nump, denomp = pade(an, 1, 2)
      assert_array_almost_equal(nump.c, [1.0 / 6, 2.0 / 3, 1.0])
      assert_array_almost_equal(denomp.c, [-1.0 / 3, 1.0])
  
      nump, denomp = pade(an, 2, 1)
      assert_array_almost_equal(nump.c, [1.0 / 3, 1.0])
      assert_array_almost_equal(denomp.c, [1.0 / 6, -2.0 / 3, 1.0])
  
      nump, denomp = pade(an, 3, 0)
      assert_array_almost_equal(nump.c, [1.0])
      assert_array_almost_equal(denomp.c, [-1.0 / 6, 0.5, -1.0, 1.0])
  
      # Testing reducing array.
      nump, denomp = pade(an, 0, 2)
      assert_array_almost_equal(nump.c, [0.5, 1.0, 1.0])
      assert_array_almost_equal(denomp.c, [1.0])
  
      nump, denomp = pade(an, 1, 1)
      assert_array_almost_equal(nump.c, [1.0 / 2, 1.0])
      assert_array_almost_equal(denomp.c, [-1.0 / 2, 1.0])
  
      nump, denomp = pade(an, 2, 0)
      assert_array_almost_equal(nump.c, [1.0])
      assert_array_almost_equal(denomp.c, [1.0 / 2, -1.0, 1.0])
  
imports: from numpy.testing import assert_array_equal, assert_array_almost_equal
  from scipy.interpolate import pade
label_desc: Use image node_id 2 for calling a global function with example usage: test_pade_4term_exp() without return types