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from math import nan, inf import pytest from numpy.core import array, arange, printoptions import numpy.polynomial as poly from numpy.testing import assert_equal, assert_ # For testing polynomial printing with object arrays from fractions import Fraction from decimal import Decimal class TestStrUnicodeSuperSubscripts: @pytest.fixture(scope='class', autouse=True) def use_unicode(self): poly.set_default_printstyle('unicode') @pytest.mark.parametrize(('inp', 'tgt'), ( ([1, 2, 3], "1.0 + 2.0·x + 3.0·x²"), ([-1, 0, 3, -1], "-1.0 + 0.0·x + 3.0·x² - 1.0·x³"), (arange(12), ("0.0 + 1.0·x + 2.0·x² + 3.0·x³ + 4.0·x⁴ + 5.0·x⁵ + " "6.0·x⁶ + 7.0·x⁷ +\n8.0·x⁸ + 9.0·x⁹ + 10.0·x¹⁰ + " "11.0·x¹¹")), )) def test_polynomial_str(self, inp, tgt): res = str(poly.Polynomial(inp)) assert_equal(res, tgt) @pytest.mark.parametrize(('inp', 'tgt'), ( ([1, 2, 3], "1.0 + 2.0·T₁(x) + 3.0·T₂(x)"), ([-1, 0, 3, -1], "-1.0 + 0.0·T₁(x) + 3.0·T₂(x) - 1.0·T₃(x)"), (arange(12), ("0.0 + 1.0·T₁(x) + 2.0·T₂(x) + 3.0·T₃(x) + 4.0·T₄(x) + " "5.0·T₅(x) +\n6.0·T₆(x) + 7.0·T₇(x) + 8.0·T₈(x) + " "9.0·T₉(x) + 10.0·T₁₀(x) + 11.0·T₁₁(x)")), )) def test_chebyshev_str(self, inp, tgt): res = str(poly.Chebyshev(inp)) assert_equal(res, tgt) @pytest.mark.parametrize(('inp', 'tgt'), ( ([1, 2, 3], "1.0 + 2.0·P₁(x) + 3.0·P₂(x)"), ([-1, 0, 3, -1], "-1.0 + 0.0·P₁(x) + 3.0·P₂(x) - 1.0·P₃(x)"), (arange(12), ("0.0 + 1.0·P₁(x) + 2.0·P₂(x) + 3.0·P₃(x) + 4.0·P₄(x) + " "5.0·P₅(x) +\n6.0·P₆(x) + 7.0·P₇(x) + 8.0·P₈(x) + " "9.0·P₉(x) + 10.0·P₁₀(x) + 11.0·P₁₁(x)")), )) def test_legendre_str(self, inp, tgt): res = str(poly.Legendre(inp)) assert_equal(res, tgt) @pytest.mark.parametrize(('inp', 'tgt'), ( ([1, 2, 3], "1.0 + 2.0·H₁(x) + 3.0·H₂(x)"), ([-1, 0, 3, -1], "-1.0 + 0.0·H₁(x) + 3.0·H₂(x) - 1.0·H₃(x)"), (arange(12), ("0.0 + 1.0·H₁(x) + 2.0·H₂(x) + 3.0·H₃(x) + 4.0·H₄(x) + " "5.0·H₅(x) +\n6.0·H₆(x) + 7.0·H₇(x) + 8.0·H₈(x) + " "9.0·H₉(x) + 10.0·H₁₀(x) + 11.0·H₁₁(x)")), )) def test_hermite_str(self, inp, tgt): res = str(poly.Hermite(inp)) assert_equal(res, tgt) @pytest.mark.parametrize(('inp', 'tgt'), ( ([1, 2, 3], "1.0 + 2.0·He₁(x) + 3.0·He₂(x)"), ([-1, 0, 3, -1], "-1.0 + 0.0·He₁(x) + 3.0·He₂(x) - 1.0·He₃(x)"), (arange(12), ("0.0 + 1.0·He₁(x) + 2.0·He₂(x) + 3.0·He₃(x) + " "4.0·He₄(x) + 5.0·He₅(x) +\n6.0·He₆(x) + 7.0·He₇(x) + " "8.0·He₈(x) + 9.0·He₉(x) + 10.0·He₁₀(x) +\n" "11.0·He₁₁(x)")), )) def test_hermiteE_str(self, inp, tgt): res = str(poly.HermiteE(inp)) assert_equal(res, tgt) @pytest.mark.parametrize(('inp', 'tgt'), ( ([1, 2, 3], "1.0 + 2.0·L₁(x) + 3.0·L₂(x)"), ([-1, 0, 3, -1], "-1.0 + 0.0·L₁(x) + 3.0·L₂(x) - 1.0·L₃(x)"), (arange(12), ("0.0 + 1.0·L₁(x) + 2.0·L₂(x) + 3.0·L₃(x) + 4.0·L₄(x) + " "5.0·L₅(x) +\n6.0·L₆(x) + 7.0·L₇(x) + 8.0·L₈(x) + " "9.0·L₉(x) + 10.0·L₁₀(x) + 11.0·L₁₁(x)")), )) def test_laguerre_str(self, inp, tgt): res = str(poly.Laguerre(inp)) assert_equal(res, tgt) class TestStrAscii: @pytest.fixture(scope='class', autouse=True) def use_ascii(self): poly.set_default_printstyle('ascii') @pytest.mark.parametrize(('inp', 'tgt'), ( ([1, 2, 3], "1.0 + 2.0 x + 3.0 x**2"), ([-1, 0, 3, -1], "-1.0 + 0.0 x + 3.0 x**2 - 1.0 x**3"), (arange(12), ("0.0 + 1.0 x + 2.0 x**2 + 3.0 x**3 + 4.0 x**4 + " "5.0 x**5 + 6.0 x**6 +\n7.0 x**7 + 8.0 x**8 + " "9.0 x**9 + 10.0 x**10 + 11.0 x**11")), )) def test_polynomial_str(self, inp, tgt): res = str(poly.Polynomial(inp)) assert_equal(res, tgt) @pytest.mark.parametrize(('inp', 'tgt'), ( ([1, 2, 3], "1.0 + 2.0 T_1(x) + 3.0 T_2(x)"), ([-1, 0, 3, -1], "-1.0 + 0.0 T_1(x) + 3.0 T_2(x) - 1.0 T_3(x)"), (arange(12), ("0.0 + 1.0 T_1(x) + 2.0 T_2(x) + 3.0 T_3(x) + " "4.0 T_4(x) + 5.0 T_5(x) +\n6.0 T_6(x) + 7.0 T_7(x) + " "8.0 T_8(x) + 9.0 T_9(x) + 10.0 T_10(x) +\n" "11.0 T_11(x)")), )) def test_chebyshev_str(self, inp, tgt): res = str(poly.Chebyshev(inp)) assert_equal(res, tgt) @pytest.mark.parametrize(('inp', 'tgt'), ( ([1, 2, 3], "1.0 + 2.0 P_1(x) + 3.0 P_2(x)"), ([-1, 0, 3, -1], "-1.0 + 0.0 P_1(x) + 3.0 P_2(x) - 1.0 P_3(x)"), (arange(12), ("0.0 + 1.0 P_1(x) + 2.0 P_2(x) + 3.0 P_3(x) + " "4.0 P_4(x) + 5.0 P_5(x) +\n6.0 P_6(x) + 7.0 P_7(x) + " "8.0 P_8(x) + 9.0 P_9(x) + 10.0 P_10(x) +\n" "11.0 P_11(x)")), )) def test_legendre_str(self, inp, tgt): res = str(poly.Legendre(inp)) assert_equal(res, tgt) @pytest.mark.parametrize(('inp', 'tgt'), ( ([1, 2, 3], "1.0 + 2.0 H_1(x) + 3.0 H_2(x)"), ([-1, 0, 3, -1], "-1.0 + 0.0 H_1(x) + 3.0 H_2(x) - 1.0 H_3(x)"), (arange(12), ("0.0 + 1.0 H_1(x) + 2.0 H_2(x) + 3.0 H_3(x) + " "4.0 H_4(x) + 5.0 H_5(x) +\n6.0 H_6(x) + 7.0 H_7(x) + " "8.0 H_8(x) + 9.0 H_9(x) + 10.0 H_10(x) +\n" "11.0 H_11(x)")), )) def test_hermite_str(self, inp, tgt): res = str(poly.Hermite(inp)) assert_equal(res, tgt) @pytest.mark.parametrize(('inp', 'tgt'), ( ([1, 2, 3], "1.0 + 2.0 He_1(x) + 3.0 He_2(x)"), ([-1, 0, 3, -1], "-1.0 + 0.0 He_1(x) + 3.0 He_2(x) - 1.0 He_3(x)"), (arange(12), ("0.0 + 1.0 He_1(x) + 2.0 He_2(x) + 3.0 He_3(x) + " "4.0 He_4(x) +\n5.0 He_5(x) + 6.0 He_6(x) + " "7.0 He_7(x) + 8.0 He_8(x) + 9.0 He_9(x) +\n" "10.0 He_10(x) + 11.0 He_11(x)")), )) def test_hermiteE_str(self, inp, tgt): res = str(poly.HermiteE(inp)) assert_equal(res, tgt) @pytest.mark.parametrize(('inp', 'tgt'), ( ([1, 2, 3], "1.0 + 2.0 L_1(x) + 3.0 L_2(x)"), ([-1, 0, 3, -1], "-1.0 + 0.0 L_1(x) + 3.0 L_2(x) - 1.0 L_3(x)"), (arange(12), ("0.0 + 1.0 L_1(x) + 2.0 L_2(x) + 3.0 L_3(x) + " "4.0 L_4(x) + 5.0 L_5(x) +\n6.0 L_6(x) + 7.0 L_7(x) + " "8.0 L_8(x) + 9.0 L_9(x) + 10.0 L_10(x) +\n" "11.0 L_11(x)")), )) def test_laguerre_str(self, inp, tgt): res = str(poly.Laguerre(inp)) assert_equal(res, tgt) class TestLinebreaking: @pytest.fixture(scope='class', autouse=True) def use_ascii(self): poly.set_default_printstyle('ascii') def test_single_line_one_less(self): # With 'ascii' style, len(str(p)) is default linewidth - 1 (i.e. 74) p = poly.Polynomial([12345678, 12345678, 12345678, 12345678, 123]) assert_equal(len(str(p)), 74) assert_equal(str(p), ( '12345678.0 + 12345678.0 x + 12345678.0 x**2 + ' '12345678.0 x**3 + 123.0 x**4' )) def test_num_chars_is_linewidth(self): # len(str(p)) == default linewidth == 75 p = poly.Polynomial([12345678, 12345678, 12345678, 12345678, 1234]) assert_equal(len(str(p)), 75) assert_equal(str(p), ( '12345678.0 + 12345678.0 x + 12345678.0 x**2 + ' '12345678.0 x**3 +\n1234.0 x**4' )) def test_first_linebreak_multiline_one_less_than_linewidth(self): # Multiline str where len(first_line) + len(next_term) == lw - 1 == 74 p = poly.Polynomial( [12345678, 12345678, 12345678, 12345678, 1, 12345678] ) assert_equal(len(str(p).split('\n')[0]), 74) assert_equal(str(p), ( '12345678.0 + 12345678.0 x + 12345678.0 x**2 + ' '12345678.0 x**3 + 1.0 x**4 +\n12345678.0 x**5' )) def test_first_linebreak_multiline_on_linewidth(self): # First line is one character longer than previous test p = poly.Polynomial( [12345678, 12345678, 12345678, 12345678.12, 1, 12345678] ) assert_equal(str(p), ( '12345678.0 + 12345678.0 x + 12345678.0 x**2 + ' '12345678.12 x**3 +\n1.0 x**4 + 12345678.0 x**5' )) @pytest.mark.parametrize(('lw', 'tgt'), ( (75, ('0.0 + 10.0 x + 200.0 x**2 + 3000.0 x**3 + 40000.0 x**4 + ' '500000.0 x**5 +\n600000.0 x**6 + 70000.0 x**7 + 8000.0 x**8 + ' '900.0 x**9')), (45, ('0.0 + 10.0 x + 200.0 x**2 + 3000.0 x**3 +\n40000.0 x**4 + ' '500000.0 x**5 +\n600000.0 x**6 + 70000.0 x**7 + 8000.0 x**8 +\n' '900.0 x**9')), (132, ('0.0 + 10.0 x + 200.0 x**2 + 3000.0 x**3 + 40000.0 x**4 + ' '500000.0 x**5 + 600000.0 x**6 + 70000.0 x**7 + 8000.0 x**8 + ' '900.0 x**9')), )) def test_linewidth_printoption(self, lw, tgt): p = poly.Polynomial( [0, 10, 200, 3000, 40000, 500000, 600000, 70000, 8000, 900] ) with printoptions(linewidth=lw): assert_equal(str(p), tgt) for line in str(p).split('\n'): assert_(len(line) < lw) def test_set_default_printoptions(): p = poly.Polynomial([1, 2, 3]) c = poly.Chebyshev([1, 2, 3]) poly.set_default_printstyle('ascii') assert_equal(str(p), "1.0 + 2.0 x + 3.0 x**2") assert_equal(str(c), "1.0 + 2.0 T_1(x) + 3.0 T_2(x)") poly.set_default_printstyle('unicode') assert_equal(str(p), "1.0 + 2.0·x + 3.0·x²") assert_equal(str(c), "1.0 + 2.0·T₁(x) + 3.0·T₂(x)") with pytest.raises(ValueError): poly.set_default_printstyle('invalid_input') def test_complex_coefficients(): """Test both numpy and built-in complex.""" coefs = [0+1j, 1+1j, -2+2j, 3+0j] # numpy complex p1 = poly.Polynomial(coefs) # Python complex p2 = poly.Polynomial(array(coefs, dtype=object)) poly.set_default_printstyle('unicode') assert_equal(str(p1), "1j + (1+1j)·x - (2-2j)·x² + (3+0j)·x³") assert_equal(str(p2), "1j + (1+1j)·x + (-2+2j)·x² + (3+0j)·x³") poly.set_default_printstyle('ascii') assert_equal(str(p1), "1j + (1+1j) x - (2-2j) x**2 + (3+0j) x**3") assert_equal(str(p2), "1j + (1+1j) x + (-2+2j) x**2 + (3+0j) x**3") @pytest.mark.parametrize(('coefs', 'tgt'), ( (array([Fraction(1, 2), Fraction(3, 4)], dtype=object), ( "1/2 + 3/4·x" )), (array([1, 2, Fraction(5, 7)], dtype=object), ( "1 + 2·x + 5/7·x²" )), (array([Decimal('1.00'), Decimal('2.2'), 3], dtype=object), ( "1.00 + 2.2·x + 3·x²" )), )) def test_numeric_object_coefficients(coefs, tgt): p = poly.Polynomial(coefs) poly.set_default_printstyle('unicode') assert_equal(str(p), tgt) @pytest.mark.parametrize(('coefs', 'tgt'), ( (array([1, 2, 'f'], dtype=object), '1 + 2·x + f·x²'), (array([1, 2, [3, 4]], dtype=object), '1 + 2·x + [3, 4]·x²'), )) def test_nonnumeric_object_coefficients(coefs, tgt): """ Test coef fallback for object arrays of non-numeric coefficients. """ p = poly.Polynomial(coefs) poly.set_default_printstyle('unicode') assert_equal(str(p), tgt) class TestFormat: def test_format_unicode(self): poly.set_default_printstyle('ascii') p = poly.Polynomial([1, 2, 0, -1]) assert_equal(format(p, 'unicode'), "1.0 + 2.0·x + 0.0·x² - 1.0·x³") def test_format_ascii(self): poly.set_default_printstyle('unicode') p = poly.Polynomial([1, 2, 0, -1]) assert_equal( format(p, 'ascii'), "1.0 + 2.0 x + 0.0 x**2 - 1.0 x**3" ) def test_empty_formatstr(self): poly.set_default_printstyle('ascii') p = poly.Polynomial([1, 2, 3]) assert_equal(format(p), "1.0 + 2.0 x + 3.0 x**2") assert_equal(f"{p}", "1.0 + 2.0 x + 3.0 x**2") def test_bad_formatstr(self): p = poly.Polynomial([1, 2, 0, -1]) with pytest.raises(ValueError): format(p, '.2f') @pytest.mark.parametrize(('poly', 'tgt'), ( (poly.Polynomial, '1.0 + 2.0·z + 3.0·z²'), (poly.Chebyshev, '1.0 + 2.0·T₁(z) + 3.0·T₂(z)'), (poly.Hermite, '1.0 + 2.0·H₁(z) + 3.0·H₂(z)'), (poly.HermiteE, '1.0 + 2.0·He₁(z) + 3.0·He₂(z)'), (poly.Laguerre, '1.0 + 2.0·L₁(z) + 3.0·L₂(z)'), (poly.Legendre, '1.0 + 2.0·P₁(z) + 3.0·P₂(z)'), )) def test_symbol(poly, tgt): p = poly([1, 2, 3], symbol='z') assert_equal(f"{p:unicode}", tgt) class TestRepr: def test_polynomial_str(self): res = repr(poly.Polynomial([0, 1])) tgt = ( "Polynomial([0., 1.], domain=[-1, 1], window=[-1, 1], " "symbol='x')" ) assert_equal(res, tgt) def test_chebyshev_str(self): res = repr(poly.Chebyshev([0, 1])) tgt = ( "Chebyshev([0., 1.], domain=[-1, 1], window=[-1, 1], " "symbol='x')" ) assert_equal(res, tgt) def test_legendre_repr(self): res = repr(poly.Legendre([0, 1])) tgt = ( "Legendre([0., 1.], domain=[-1, 1], window=[-1, 1], " "symbol='x')" ) assert_equal(res, tgt) def test_hermite_repr(self): res = repr(poly.Hermite([0, 1])) tgt = ( "Hermite([0., 1.], domain=[-1, 1], window=[-1, 1], " "symbol='x')" ) assert_equal(res, tgt) def test_hermiteE_repr(self): res = repr(poly.HermiteE([0, 1])) tgt = ( "HermiteE([0., 1.], domain=[-1, 1], window=[-1, 1], " "symbol='x')" ) assert_equal(res, tgt) def test_laguerre_repr(self): res = repr(poly.Laguerre([0, 1])) tgt = ( "Laguerre([0., 1.], domain=[0, 1], window=[0, 1], " "symbol='x')" ) assert_equal(res, tgt) class TestLatexRepr: """Test the latex repr used by Jupyter""" def as_latex(self, obj): # right now we ignore the formatting of scalars in our tests, since # it makes them too verbose. Ideally, the formatting of scalars will # be fixed such that tests below continue to pass obj._repr_latex_scalar = lambda x, parens=False: str(x) try: return obj._repr_latex_() finally: del obj._repr_latex_scalar def test_simple_polynomial(self): # default input p = poly.Polynomial([1, 2, 3]) assert_equal(self.as_latex(p), r'$x \mapsto 1.0 + 2.0\,x + 3.0\,x^{2}$') # translated input p = poly.Polynomial([1, 2, 3], domain=[-2, 0]) assert_equal(self.as_latex(p), r'$x \mapsto 1.0 + 2.0\,\left(1.0 + x\right) + 3.0\,\left(1.0 + x\right)^{2}$') # scaled input p = poly.Polynomial([1, 2, 3], domain=[-0.5, 0.5]) assert_equal(self.as_latex(p), r'$x \mapsto 1.0 + 2.0\,\left(2.0x\right) + 3.0\,\left(2.0x\right)^{2}$') # affine input p = poly.Polynomial([1, 2, 3], domain=[-1, 0]) assert_equal(self.as_latex(p), r'$x \mapsto 1.0 + 2.0\,\left(1.0 + 2.0x\right) + 3.0\,\left(1.0 + 2.0x\right)^{2}$') def test_basis_func(self): p = poly.Chebyshev([1, 2, 3]) assert_equal(self.as_latex(p), r'$x \mapsto 1.0\,{T}_{0}(x) + 2.0\,{T}_{1}(x) + 3.0\,{T}_{2}(x)$') # affine input - check no surplus parens are added p = poly.Chebyshev([1, 2, 3], domain=[-1, 0]) assert_equal(self.as_latex(p), r'$x \mapsto 1.0\,{T}_{0}(1.0 + 2.0x) + 2.0\,{T}_{1}(1.0 + 2.0x) + 3.0\,{T}_{2}(1.0 + 2.0x)$') def test_multichar_basis_func(self): p = poly.HermiteE([1, 2, 3]) assert_equal(self.as_latex(p), r'$x \mapsto 1.0\,{He}_{0}(x) + 2.0\,{He}_{1}(x) + 3.0\,{He}_{2}(x)$') def test_symbol_basic(self): # default input p = poly.Polynomial([1, 2, 3], symbol='z') assert_equal(self.as_latex(p), r'$z \mapsto 1.0 + 2.0\,z + 3.0\,z^{2}$') # translated input p = poly.Polynomial([1, 2, 3], domain=[-2, 0], symbol='z') assert_equal( self.as_latex(p), ( r'$z \mapsto 1.0 + 2.0\,\left(1.0 + z\right) + 3.0\,' r'\left(1.0 + z\right)^{2}$' ), ) # scaled input p = poly.Polynomial([1, 2, 3], domain=[-0.5, 0.5], symbol='z') assert_equal( self.as_latex(p), ( r'$z \mapsto 1.0 + 2.0\,\left(2.0z\right) + 3.0\,' r'\left(2.0z\right)^{2}$' ), ) # affine input p = poly.Polynomial([1, 2, 3], domain=[-1, 0], symbol='z') assert_equal( self.as_latex(p), ( r'$z \mapsto 1.0 + 2.0\,\left(1.0 + 2.0z\right) + 3.0\,' r'\left(1.0 + 2.0z\right)^{2}$' ), ) SWITCH_TO_EXP = ( '1.0 + (1.0e-01) x + (1.0e-02) x**2', '1.2 + (1.2e-01) x + (1.2e-02) x**2', '1.23 + 0.12 x + (1.23e-02) x**2 + (1.23e-03) x**3', '1.235 + 0.123 x + (1.235e-02) x**2 + (1.235e-03) x**3', '1.2346 + 0.1235 x + 0.0123 x**2 + (1.2346e-03) x**3 + (1.2346e-04) x**4', '1.23457 + 0.12346 x + 0.01235 x**2 + (1.23457e-03) x**3 + ' '(1.23457e-04) x**4', '1.234568 + 0.123457 x + 0.012346 x**2 + 0.001235 x**3 + ' '(1.234568e-04) x**4 + (1.234568e-05) x**5', '1.2345679 + 0.1234568 x + 0.0123457 x**2 + 0.0012346 x**3 + ' '(1.2345679e-04) x**4 + (1.2345679e-05) x**5') class TestPrintOptions: """ Test the output is properly configured via printoptions. The exponential notation is enabled automatically when the values are too small or too large. """ @pytest.fixture(scope='class', autouse=True) def use_ascii(self): poly.set_default_printstyle('ascii') def test_str(self): p = poly.Polynomial([1/2, 1/7, 1/7*10**8, 1/7*10**9]) assert_equal(str(p), '0.5 + 0.14285714 x + 14285714.28571429 x**2 ' '+ (1.42857143e+08) x**3') with printoptions(precision=3): assert_equal(str(p), '0.5 + 0.143 x + 14285714.286 x**2 ' '+ (1.429e+08) x**3') def test_latex(self): p = poly.Polynomial([1/2, 1/7, 1/7*10**8, 1/7*10**9]) assert_equal(p._repr_latex_(), r'$x \mapsto \text{0.5} + \text{0.14285714}\,x + ' r'\text{14285714.28571429}\,x^{2} + ' r'\text{(1.42857143e+08)}\,x^{3}$') with printoptions(precision=3): assert_equal(p._repr_latex_(), r'$x \mapsto \text{0.5} + \text{0.143}\,x + ' r'\text{14285714.286}\,x^{2} + \text{(1.429e+08)}\,x^{3}$') def test_fixed(self): p = poly.Polynomial([1/2]) assert_equal(str(p), '0.5') with printoptions(floatmode='fixed'): assert_equal(str(p), '0.50000000') with printoptions(floatmode='fixed', precision=4): assert_equal(str(p), '0.5000') def test_switch_to_exp(self): for i, s in enumerate(SWITCH_TO_EXP): with printoptions(precision=i): p = poly.Polynomial([1.23456789*10**-i for i in range(i//2+3)]) assert str(p).replace('\n', ' ') == s def test_non_finite(self): p = poly.Polynomial([nan, inf]) assert str(p) == 'nan + inf x' assert p._repr_latex_() == r'$x \mapsto \text{nan} + \text{inf}\,x$' with printoptions(nanstr='NAN', infstr='INF'): assert str(p) == 'NAN + INF x' assert p._repr_latex_() == \ r'$x \mapsto \text{NAN} + \text{INF}\,x$'