from sympy.core.mod import Mod from sympy.core.numbers import (I, oo, pi) from sympy.functions.combinatorial.factorials import factorial from sympy.functions.elementary.exponential import (exp, log) from sympy.functions.elementary.miscellaneous import sqrt from sympy.functions.elementary.trigonometric import (asin, sin) from sympy.simplify.simplify import simplify from sympy.core import Symbol, S, Rational, Integer, Dummy, Wild, Pow from sympy.core.assumptions import (assumptions, check_assumptions, failing_assumptions, common_assumptions, _generate_assumption_rules, _load_pre_generated_assumption_rules) from sympy.core.facts import InconsistentAssumptions from sympy.core.random import seed from sympy.combinatorics import Permutation from sympy.combinatorics.perm_groups import PermutationGroup from sympy.testing.pytest import raises, XFAIL def test_symbol_unset(): x = Symbol('x', real=True, integer=True) assert x.is_real is True assert x.is_integer is True assert x.is_imaginary is False assert x.is_noninteger is False assert x.is_number is False def test_zero(): z = Integer(0) assert z.is_commutative is True assert z.is_integer is True assert z.is_rational is True assert z.is_algebraic is True assert z.is_transcendental is False assert z.is_real is True assert z.is_complex is True assert z.is_noninteger is False assert z.is_irrational is False assert z.is_imaginary is False assert z.is_positive is False assert z.is_negative is False assert z.is_nonpositive is True assert z.is_nonnegative is True assert z.is_even is True assert z.is_odd is False assert z.is_finite is True assert z.is_infinite is False assert z.is_comparable is True assert z.is_prime is False assert z.is_composite is False assert z.is_number is True def test_one(): z = Integer(1) assert z.is_commutative is True assert z.is_integer is True assert z.is_rational is True assert z.is_algebraic is True assert z.is_transcendental is False assert z.is_real is True assert z.is_complex is True assert z.is_noninteger is False assert z.is_irrational is False assert z.is_imaginary is False assert z.is_positive is True assert z.is_negative is False assert z.is_nonpositive is False assert z.is_nonnegative is True assert z.is_even is False assert z.is_odd is True assert z.is_finite is True assert z.is_infinite is False assert z.is_comparable is True assert z.is_prime is False assert z.is_number is True assert z.is_composite is False # issue 8807 def test_negativeone(): z = Integer(-1) assert z.is_commutative is True assert z.is_integer is True assert z.is_rational is True assert z.is_algebraic is True assert z.is_transcendental is False assert z.is_real is True assert z.is_complex is True assert z.is_noninteger is False assert z.is_irrational is False assert z.is_imaginary is False assert z.is_positive is False assert z.is_negative is True assert z.is_nonpositive is True assert z.is_nonnegative is False assert z.is_even is False assert z.is_odd is True assert z.is_finite is True assert z.is_infinite is False assert z.is_comparable is True assert z.is_prime is False assert z.is_composite is False assert z.is_number is True def test_infinity(): oo = S.Infinity assert oo.is_commutative is True assert oo.is_integer is False assert oo.is_rational is False assert oo.is_algebraic is False assert oo.is_transcendental is False assert oo.is_extended_real is True assert oo.is_real is False assert oo.is_complex is False assert oo.is_noninteger is True assert oo.is_irrational is False assert oo.is_imaginary is False assert oo.is_nonzero is False assert oo.is_positive is False assert oo.is_negative is False assert oo.is_nonpositive is False assert oo.is_nonnegative is False assert oo.is_extended_nonzero is True assert oo.is_extended_positive is True assert oo.is_extended_negative is False assert oo.is_extended_nonpositive is False assert oo.is_extended_nonnegative is True assert oo.is_even is False assert oo.is_odd is False assert oo.is_finite is False assert oo.is_infinite is True assert oo.is_comparable is True assert oo.is_prime is False assert oo.is_composite is False assert oo.is_number is True def test_neg_infinity(): mm = S.NegativeInfinity assert mm.is_commutative is True assert mm.is_integer is False assert mm.is_rational is False assert mm.is_algebraic is False assert mm.is_transcendental is False assert mm.is_extended_real is True assert mm.is_real is False assert mm.is_complex is False assert mm.is_noninteger is True assert mm.is_irrational is False assert mm.is_imaginary is False assert mm.is_nonzero is False assert mm.is_positive is False assert mm.is_negative is False assert mm.is_nonpositive is False assert mm.is_nonnegative is False assert mm.is_extended_nonzero is True assert mm.is_extended_positive is False assert mm.is_extended_negative is True assert mm.is_extended_nonpositive is True assert mm.is_extended_nonnegative is False assert mm.is_even is False assert mm.is_odd is False assert mm.is_finite is False assert mm.is_infinite is True assert mm.is_comparable is True assert mm.is_prime is False assert mm.is_composite is False assert mm.is_number is True def test_zoo(): zoo = S.ComplexInfinity assert zoo.is_complex is False assert zoo.is_real is False assert zoo.is_prime is False def test_nan(): nan = S.NaN assert nan.is_commutative is True assert nan.is_integer is None assert nan.is_rational is None assert nan.is_algebraic is None assert nan.is_transcendental is None assert nan.is_real is None assert nan.is_complex is None assert nan.is_noninteger is None assert nan.is_irrational is None assert nan.is_imaginary is None assert nan.is_positive is None assert nan.is_negative is None assert nan.is_nonpositive is None assert nan.is_nonnegative is None assert nan.is_even is None assert nan.is_odd is None assert nan.is_finite is None assert nan.is_infinite is None assert nan.is_comparable is False assert nan.is_prime is None assert nan.is_composite is None assert nan.is_number is True def test_pos_rational(): r = Rational(3, 4) assert r.is_commutative is True assert r.is_integer is False assert r.is_rational is True assert r.is_algebraic is True assert r.is_transcendental is False assert r.is_real is True assert r.is_complex is True assert r.is_noninteger is True assert r.is_irrational is False assert r.is_imaginary is False assert r.is_positive is True assert r.is_negative is False assert r.is_nonpositive is False assert r.is_nonnegative is True assert r.is_even is False assert r.is_odd is False assert r.is_finite is True assert r.is_infinite is False assert r.is_comparable is True assert r.is_prime is False assert r.is_composite is False r = Rational(1, 4) assert r.is_nonpositive is False assert r.is_positive is True assert r.is_negative is False assert r.is_nonnegative is True r = Rational(5, 4) assert r.is_negative is False assert r.is_positive is True assert r.is_nonpositive is False assert r.is_nonnegative is True r = Rational(5, 3) assert r.is_nonnegative is True assert r.is_positive is True assert r.is_negative is False assert r.is_nonpositive is False def test_neg_rational(): r = Rational(-3, 4) assert r.is_positive is False assert r.is_nonpositive is True assert r.is_negative is True assert r.is_nonnegative is False r = Rational(-1, 4) assert r.is_nonpositive is True assert r.is_positive is False assert r.is_negative is True assert r.is_nonnegative is False r = Rational(-5, 4) assert r.is_negative is True assert r.is_positive is False assert r.is_nonpositive is True assert r.is_nonnegative is False r = Rational(-5, 3) assert r.is_nonnegative is False assert r.is_positive is False assert r.is_negative is True assert r.is_nonpositive is True def test_pi(): z = S.Pi assert z.is_commutative is True assert z.is_integer is False assert z.is_rational is False assert z.is_algebraic is False assert z.is_transcendental is True assert z.is_real is True assert z.is_complex is True assert z.is_noninteger is True assert z.is_irrational is True assert z.is_imaginary is False assert z.is_positive is True assert z.is_negative is False assert z.is_nonpositive is False assert z.is_nonnegative is True assert z.is_even is False assert z.is_odd is False assert z.is_finite is True assert z.is_infinite is False assert z.is_comparable is True assert z.is_prime is False assert z.is_composite is False def test_E(): z = S.Exp1 assert z.is_commutative is True assert z.is_integer is False assert z.is_rational is False assert z.is_algebraic is False assert z.is_transcendental is True assert z.is_real is True assert z.is_complex is True assert z.is_noninteger is True assert z.is_irrational is True assert z.is_imaginary is False assert z.is_positive is True assert z.is_negative is False assert z.is_nonpositive is False assert z.is_nonnegative is True assert z.is_even is False assert z.is_odd is False assert z.is_finite is True assert z.is_infinite is False assert z.is_comparable is True assert z.is_prime is False assert z.is_composite is False def test_I(): z = S.ImaginaryUnit assert z.is_commutative is True assert z.is_integer is False assert z.is_rational is False assert z.is_algebraic is True assert z.is_transcendental is False assert z.is_real is False assert z.is_complex is True assert z.is_noninteger is False assert z.is_irrational is False assert z.is_imaginary is True assert z.is_positive is False assert z.is_negative is False assert z.is_nonpositive is False assert z.is_nonnegative is False assert z.is_even is False assert z.is_odd is False assert z.is_finite is True assert z.is_infinite is False assert z.is_comparable is False assert z.is_prime is False assert z.is_composite is False def test_symbol_real_false(): # issue 3848 a = Symbol('a', real=False) assert a.is_real is False assert a.is_integer is False assert a.is_zero is False assert a.is_negative is False assert a.is_positive is False assert a.is_nonnegative is False assert a.is_nonpositive is False assert a.is_nonzero is False assert a.is_extended_negative is None assert a.is_extended_positive is None assert a.is_extended_nonnegative is None assert a.is_extended_nonpositive is None assert a.is_extended_nonzero is None def test_symbol_extended_real_false(): # issue 3848 a = Symbol('a', extended_real=False) assert a.is_real is False assert a.is_integer is False assert a.is_zero is False assert a.is_negative is False assert a.is_positive is False assert a.is_nonnegative is False assert a.is_nonpositive is False assert a.is_nonzero is False assert a.is_extended_negative is False assert a.is_extended_positive is False assert a.is_extended_nonnegative is False assert a.is_extended_nonpositive is False assert a.is_extended_nonzero is False def test_symbol_imaginary(): a = Symbol('a', imaginary=True) assert a.is_real is False assert a.is_integer is False assert a.is_negative is False assert a.is_positive is False assert a.is_nonnegative is False assert a.is_nonpositive is False assert a.is_zero is False assert a.is_nonzero is False # since nonzero -> real def test_symbol_zero(): x = Symbol('x', zero=True) assert x.is_positive is False assert x.is_nonpositive assert x.is_negative is False assert x.is_nonnegative assert x.is_zero is True # TODO Change to x.is_nonzero is None # See https://github.com/sympy/sympy/pull/9583 assert x.is_nonzero is False assert x.is_finite is True def test_symbol_positive(): x = Symbol('x', positive=True) assert x.is_positive is True assert x.is_nonpositive is False assert x.is_negative is False assert x.is_nonnegative is True assert x.is_zero is False assert x.is_nonzero is True def test_neg_symbol_positive(): x = -Symbol('x', positive=True) assert x.is_positive is False assert x.is_nonpositive is True assert x.is_negative is True assert x.is_nonnegative is False assert x.is_zero is False assert x.is_nonzero is True def test_symbol_nonpositive(): x = Symbol('x', nonpositive=True) assert x.is_positive is False assert x.is_nonpositive is True assert x.is_negative is None assert x.is_nonnegative is None assert x.is_zero is None assert x.is_nonzero is None def test_neg_symbol_nonpositive(): x = -Symbol('x', nonpositive=True) assert x.is_positive is None assert x.is_nonpositive is None assert x.is_negative is False assert x.is_nonnegative is True assert x.is_zero is None assert x.is_nonzero is None def test_symbol_falsepositive(): x = Symbol('x', positive=False) assert x.is_positive is False assert x.is_nonpositive is None assert x.is_negative is None assert x.is_nonnegative is None assert x.is_zero is None assert x.is_nonzero is None def test_symbol_falsepositive_mul(): # To test pull request 9379 # Explicit handling of arg.is_positive=False was added to Mul._eval_is_positive x = 2*Symbol('x', positive=False) assert x.is_positive is False # This was None before assert x.is_nonpositive is None assert x.is_negative is None assert x.is_nonnegative is None assert x.is_zero is None assert x.is_nonzero is None @XFAIL def test_symbol_infinitereal_mul(): ix = Symbol('ix', infinite=True, extended_real=True) assert (-ix).is_extended_positive is None def test_neg_symbol_falsepositive(): x = -Symbol('x', positive=False) assert x.is_positive is None assert x.is_nonpositive is None assert x.is_negative is False assert x.is_nonnegative is None assert x.is_zero is None assert x.is_nonzero is None def test_neg_symbol_falsenegative(): # To test pull request 9379 # Explicit handling of arg.is_negative=False was added to Mul._eval_is_positive x = -Symbol('x', negative=False) assert x.is_positive is False # This was None before assert x.is_nonpositive is None assert x.is_negative is None assert x.is_nonnegative is None assert x.is_zero is None assert x.is_nonzero is None def test_symbol_falsepositive_real(): x = Symbol('x', positive=False, real=True) assert x.is_positive is False assert x.is_nonpositive is True assert x.is_negative is None assert x.is_nonnegative is None assert x.is_zero is None assert x.is_nonzero is None def test_neg_symbol_falsepositive_real(): x = -Symbol('x', positive=False, real=True) assert x.is_positive is None assert x.is_nonpositive is None assert x.is_negative is False assert x.is_nonnegative is True assert x.is_zero is None assert x.is_nonzero is None def test_symbol_falsenonnegative(): x = Symbol('x', nonnegative=False) assert x.is_positive is False assert x.is_nonpositive is None assert x.is_negative is None assert x.is_nonnegative is False assert x.is_zero is False assert x.is_nonzero is None @XFAIL def test_neg_symbol_falsenonnegative(): x = -Symbol('x', nonnegative=False) assert x.is_positive is None assert x.is_nonpositive is False # this currently returns None assert x.is_negative is False # this currently returns None assert x.is_nonnegative is None assert x.is_zero is False # this currently returns None assert x.is_nonzero is True # this currently returns None def test_symbol_falsenonnegative_real(): x = Symbol('x', nonnegative=False, real=True) assert x.is_positive is False assert x.is_nonpositive is True assert x.is_negative is True assert x.is_nonnegative is False assert x.is_zero is False assert x.is_nonzero is True def test_neg_symbol_falsenonnegative_real(): x = -Symbol('x', nonnegative=False, real=True) assert x.is_positive is True assert x.is_nonpositive is False assert x.is_negative is False assert x.is_nonnegative is True assert x.is_zero is False assert x.is_nonzero is True def test_prime(): assert S.NegativeOne.is_prime is False assert S(-2).is_prime is False assert S(-4).is_prime is False assert S.Zero.is_prime is False assert S.One.is_prime is False assert S(2).is_prime is True assert S(17).is_prime is True assert S(4).is_prime is False def test_composite(): assert S.NegativeOne.is_composite is False assert S(-2).is_composite is False assert S(-4).is_composite is False assert S.Zero.is_composite is False assert S(2).is_composite is False assert S(17).is_composite is False assert S(4).is_composite is True x = Dummy(integer=True, positive=True, prime=False) assert x.is_composite is None # x could be 1 assert (x + 1).is_composite is None x = Dummy(positive=True, even=True, prime=False) assert x.is_integer is True assert x.is_composite is True def test_prime_symbol(): x = Symbol('x', prime=True) assert x.is_prime is True assert x.is_integer is True assert x.is_positive is True assert x.is_negative is False assert x.is_nonpositive is False assert x.is_nonnegative is True x = Symbol('x', prime=False) assert x.is_prime is False assert x.is_integer is None assert x.is_positive is None assert x.is_negative is None assert x.is_nonpositive is None assert x.is_nonnegative is None def test_symbol_noncommutative(): x = Symbol('x', commutative=True) assert x.is_complex is None x = Symbol('x', commutative=False) assert x.is_integer is False assert x.is_rational is False assert x.is_algebraic is False assert x.is_irrational is False assert x.is_real is False assert x.is_complex is False def test_other_symbol(): x = Symbol('x', integer=True) assert x.is_integer is True assert x.is_real is True assert x.is_finite is True x = Symbol('x', integer=True, nonnegative=True) assert x.is_integer is True assert x.is_nonnegative is True assert x.is_negative is False assert x.is_positive is None assert x.is_finite is True x = Symbol('x', integer=True, nonpositive=True) assert x.is_integer is True assert x.is_nonpositive is True assert x.is_positive is False assert x.is_negative is None assert x.is_finite is True x = Symbol('x', odd=True) assert x.is_odd is True assert x.is_even is False assert x.is_integer is True assert x.is_finite is True x = Symbol('x', odd=False) assert x.is_odd is False assert x.is_even is None assert x.is_integer is None assert x.is_finite is None x = Symbol('x', even=True) assert x.is_even is True assert x.is_odd is False assert x.is_integer is True assert x.is_finite is True x = Symbol('x', even=False) assert x.is_even is False assert x.is_odd is None assert x.is_integer is None assert x.is_finite is None x = Symbol('x', integer=True, nonnegative=True) assert x.is_integer is True assert x.is_nonnegative is True assert x.is_finite is True x = Symbol('x', integer=True, nonpositive=True) assert x.is_integer is True assert x.is_nonpositive is True assert x.is_finite is True x = Symbol('x', rational=True) assert x.is_real is True assert x.is_finite is True x = Symbol('x', rational=False) assert x.is_real is None assert x.is_finite is None x = Symbol('x', irrational=True) assert x.is_real is True assert x.is_finite is True x = Symbol('x', irrational=False) assert x.is_real is None assert x.is_finite is None with raises(AttributeError): x.is_real = False x = Symbol('x', algebraic=True) assert x.is_transcendental is False x = Symbol('x', transcendental=True) assert x.is_algebraic is False assert x.is_rational is False assert x.is_integer is False def test_evaluate_false(): # Previously this failed because the assumptions query would make new # expressions and some of the evaluation logic would fail under # evaluate(False). from sympy.core.parameters import evaluate from sympy.abc import x, h f = 2**x**7 with evaluate(False): fh = f.xreplace({x: x+h}) assert fh.exp.is_rational is None def test_issue_3825(): """catch: hash instability""" x = Symbol("x") y = Symbol("y") a1 = x + y a2 = y + x a2.is_comparable h1 = hash(a1) h2 = hash(a2) assert h1 == h2 def test_issue_4822(): z = (-1)**Rational(1, 3)*(1 - I*sqrt(3)) assert z.is_real in [True, None] def test_hash_vs_typeinfo(): """seemingly different typeinfo, but in fact equal""" # the following two are semantically equal x1 = Symbol('x', even=True) x2 = Symbol('x', integer=True, odd=False) assert hash(x1) == hash(x2) assert x1 == x2 def test_hash_vs_typeinfo_2(): """different typeinfo should mean !eq""" # the following two are semantically different x = Symbol('x') x1 = Symbol('x', even=True) assert x != x1 assert hash(x) != hash(x1) # This might fail with very low probability def test_hash_vs_eq(): """catch: different hash for equal objects""" a = 1 + S.Pi # important: do not fold it into a Number instance ha = hash(a) # it should be Add/Mul/... to trigger the bug a.is_positive # this uses .evalf() and deduces it is positive assert a.is_positive is True # be sure that hash stayed the same assert ha == hash(a) # now b should be the same expression b = a.expand(trig=True) hb = hash(b) assert a == b assert ha == hb def test_Add_is_pos_neg(): # these cover lines not covered by the rest of tests in core n = Symbol('n', extended_negative=True, infinite=True) nn = Symbol('n', extended_nonnegative=True, infinite=True) np = Symbol('n', extended_nonpositive=True, infinite=True) p = Symbol('p', extended_positive=True, infinite=True) r = Dummy(extended_real=True, finite=False) x = Symbol('x') xf = Symbol('xf', finite=True) assert (n + p).is_extended_positive is None assert (n + x).is_extended_positive is None assert (p + x).is_extended_positive is None assert (n + p).is_extended_negative is None assert (n + x).is_extended_negative is None assert (p + x).is_extended_negative is None assert (n + xf).is_extended_positive is False assert (p + xf).is_extended_positive is True assert (n + xf).is_extended_negative is True assert (p + xf).is_extended_negative is False assert (x - S.Infinity).is_extended_negative is None # issue 7798 # issue 8046, 16.2 assert (p + nn).is_extended_positive assert (n + np).is_extended_negative assert (p + r).is_extended_positive is None def test_Add_is_imaginary(): nn = Dummy(nonnegative=True) assert (I*nn + I).is_imaginary # issue 8046, 17 def test_Add_is_algebraic(): a = Symbol('a', algebraic=True) b = Symbol('a', algebraic=True) na = Symbol('na', algebraic=False) nb = Symbol('nb', algebraic=False) x = Symbol('x') assert (a + b).is_algebraic assert (na + nb).is_algebraic is None assert (a + na).is_algebraic is False assert (a + x).is_algebraic is None assert (na + x).is_algebraic is None def test_Mul_is_algebraic(): a = Symbol('a', algebraic=True) b = Symbol('b', algebraic=True) na = Symbol('na', algebraic=False) an = Symbol('an', algebraic=True, nonzero=True) nb = Symbol('nb', algebraic=False) x = Symbol('x') assert (a*b).is_algebraic is True assert (na*nb).is_algebraic is None assert (a*na).is_algebraic is None assert (an*na).is_algebraic is False assert (a*x).is_algebraic is None assert (na*x).is_algebraic is None def test_Pow_is_algebraic(): e = Symbol('e', algebraic=True) assert Pow(1, e, evaluate=False).is_algebraic assert Pow(0, e, evaluate=False).is_algebraic a = Symbol('a', algebraic=True) azf = Symbol('azf', algebraic=True, zero=False) na = Symbol('na', algebraic=False) ia = Symbol('ia', algebraic=True, irrational=True) ib = Symbol('ib', algebraic=True, irrational=True) r = Symbol('r', rational=True) x = Symbol('x') assert (a**2).is_algebraic is True assert (a**r).is_algebraic is None assert (azf**r).is_algebraic is True assert (a**x).is_algebraic is None assert (na**r).is_algebraic is None assert (ia**r).is_algebraic is True assert (ia**ib).is_algebraic is False assert (a**e).is_algebraic is None # Gelfond-Schneider constant: assert Pow(2, sqrt(2), evaluate=False).is_algebraic is False assert Pow(S.GoldenRatio, sqrt(3), evaluate=False).is_algebraic is False # issue 8649 t = Symbol('t', real=True, transcendental=True) n = Symbol('n', integer=True) assert (t**n).is_algebraic is None assert (t**n).is_integer is None assert (pi**3).is_algebraic is False r = Symbol('r', zero=True) assert (pi**r).is_algebraic is True def test_Mul_is_prime_composite(): x = Symbol('x', positive=True, integer=True) y = Symbol('y', positive=True, integer=True) assert (x*y).is_prime is None assert ( (x+1)*(y+1) ).is_prime is False assert ( (x+1)*(y+1) ).is_composite is True x = Symbol('x', positive=True) assert ( (x+1)*(y+1) ).is_prime is None assert ( (x+1)*(y+1) ).is_composite is None def test_Pow_is_pos_neg(): z = Symbol('z', real=True) w = Symbol('w', nonpositive=True) assert (S.NegativeOne**S(2)).is_positive is True assert (S.One**z).is_positive is True assert (S.NegativeOne**S(3)).is_positive is False assert (S.Zero**S.Zero).is_positive is True # 0**0 is 1 assert (w**S(3)).is_positive is False assert (w**S(2)).is_positive is None assert (I**2).is_positive is False assert (I**4).is_positive is True # tests emerging from #16332 issue p = Symbol('p', zero=True) q = Symbol('q', zero=False, real=True) j = Symbol('j', zero=False, even=True) x = Symbol('x', zero=True) y = Symbol('y', zero=True) assert (p**q).is_positive is False assert (p**q).is_negative is False assert (p**j).is_positive is False assert (x**y).is_positive is True # 0**0 assert (x**y).is_negative is False def test_Pow_is_prime_composite(): x = Symbol('x', positive=True, integer=True) y = Symbol('y', positive=True, integer=True) assert (x**y).is_prime is None assert ( x**(y+1) ).is_prime is False assert ( x**(y+1) ).is_composite is None assert ( (x+1)**(y+1) ).is_composite is True assert ( (-x-1)**(2*y) ).is_composite is True x = Symbol('x', positive=True) assert (x**y).is_prime is None def test_Mul_is_infinite(): x = Symbol('x') f = Symbol('f', finite=True) i = Symbol('i', infinite=True) z = Dummy(zero=True) nzf = Dummy(finite=True, zero=False) from sympy.core.mul import Mul assert (x*f).is_finite is None assert (x*i).is_finite is None assert (f*i).is_finite is None assert (x*f*i).is_finite is None assert (z*i).is_finite is None assert (nzf*i).is_finite is False assert (z*f).is_finite is True assert Mul(0, f, evaluate=False).is_finite is True assert Mul(0, i, evaluate=False).is_finite is None assert (x*f).is_infinite is None assert (x*i).is_infinite is None assert (f*i).is_infinite is None assert (x*f*i).is_infinite is None assert (z*i).is_infinite is S.NaN.is_infinite assert (nzf*i).is_infinite is True assert (z*f).is_infinite is False assert Mul(0, f, evaluate=False).is_infinite is False assert Mul(0, i, evaluate=False).is_infinite is S.NaN.is_infinite def test_Add_is_infinite(): x = Symbol('x') f = Symbol('f', finite=True) i = Symbol('i', infinite=True) i2 = Symbol('i2', infinite=True) z = Dummy(zero=True) nzf = Dummy(finite=True, zero=False) from sympy.core.add import Add assert (x+f).is_finite is None assert (x+i).is_finite is None assert (f+i).is_finite is False assert (x+f+i).is_finite is None assert (z+i).is_finite is False assert (nzf+i).is_finite is False assert (z+f).is_finite is True assert (i+i2).is_finite is None assert Add(0, f, evaluate=False).is_finite is True assert Add(0, i, evaluate=False).is_finite is False assert (x+f).is_infinite is None assert (x+i).is_infinite is None assert (f+i).is_infinite is True assert (x+f+i).is_infinite is None assert (z+i).is_infinite is True assert (nzf+i).is_infinite is True assert (z+f).is_infinite is False assert (i+i2).is_infinite is None assert Add(0, f, evaluate=False).is_infinite is False assert Add(0, i, evaluate=False).is_infinite is True def test_special_is_rational(): i = Symbol('i', integer=True) i2 = Symbol('i2', integer=True) ni = Symbol('ni', integer=True, nonzero=True) r = Symbol('r', rational=True) rn = Symbol('r', rational=True, nonzero=True) nr = Symbol('nr', irrational=True) x = Symbol('x') assert sqrt(3).is_rational is False assert (3 + sqrt(3)).is_rational is False assert (3*sqrt(3)).is_rational is False assert exp(3).is_rational is False assert exp(ni).is_rational is False assert exp(rn).is_rational is False assert exp(x).is_rational is None assert exp(log(3), evaluate=False).is_rational is True assert log(exp(3), evaluate=False).is_rational is True assert log(3).is_rational is False assert log(ni + 1).is_rational is False assert log(rn + 1).is_rational is False assert log(x).is_rational is None assert (sqrt(3) + sqrt(5)).is_rational is None assert (sqrt(3) + S.Pi).is_rational is False assert (x**i).is_rational is None assert (i**i).is_rational is True assert (i**i2).is_rational is None assert (r**i).is_rational is None assert (r**r).is_rational is None assert (r**x).is_rational is None assert (nr**i).is_rational is None # issue 8598 assert (nr**Symbol('z', zero=True)).is_rational assert sin(1).is_rational is False assert sin(ni).is_rational is False assert sin(rn).is_rational is False assert sin(x).is_rational is None assert asin(r).is_rational is False assert sin(asin(3), evaluate=False).is_rational is True @XFAIL def test_issue_6275(): x = Symbol('x') # both zero or both Muls...but neither "change would be very appreciated. # This is similar to x/x => 1 even though if x = 0, it is really nan. assert isinstance(x*0, type(0*S.Infinity)) if 0*S.Infinity is S.NaN: b = Symbol('b', finite=None) assert (b*0).is_zero is None def test_sanitize_assumptions(): # issue 6666 for cls in (Symbol, Dummy, Wild): x = cls('x', real=1, positive=0) assert x.is_real is True assert x.is_positive is False assert cls('', real=True, positive=None).is_positive is None raises(ValueError, lambda: cls('', commutative=None)) raises(ValueError, lambda: Symbol._sanitize({"commutative": None})) def test_special_assumptions(): e = -3 - sqrt(5) + (-sqrt(10)/2 - sqrt(2)/2)**2 assert simplify(e < 0) is S.false assert simplify(e > 0) is S.false assert (e == 0) is False # it's not a literal 0 assert e.equals(0) is True def test_inconsistent(): # cf. issues 5795 and 5545 raises(InconsistentAssumptions, lambda: Symbol('x', real=True, commutative=False)) def test_issue_6631(): assert ((-1)**(I)).is_real is True assert ((-1)**(I*2)).is_real is True assert ((-1)**(I/2)).is_real is True assert ((-1)**(I*S.Pi)).is_real is True assert (I**(I + 2)).is_real is True def test_issue_2730(): assert (1/(1 + I)).is_real is False def test_issue_4149(): assert (3 + I).is_complex assert (3 + I).is_imaginary is False assert (3*I + S.Pi*I).is_imaginary # as Zero.is_imaginary is False, see issue 7649 y = Symbol('y', real=True) assert (3*I + S.Pi*I + y*I).is_imaginary is None p = Symbol('p', positive=True) assert (3*I + S.Pi*I + p*I).is_imaginary n = Symbol('n', negative=True) assert (-3*I - S.Pi*I + n*I).is_imaginary i = Symbol('i', imaginary=True) assert ([(i**a).is_imaginary for a in range(4)] == [False, True, False, True]) # tests from the PR #7887: e = S("-sqrt(3)*I/2 + 0.866025403784439*I") assert e.is_real is False assert e.is_imaginary def test_issue_2920(): n = Symbol('n', negative=True) assert sqrt(n).is_imaginary def test_issue_7899(): x = Symbol('x', real=True) assert (I*x).is_real is None assert ((x - I)*(x - 1)).is_zero is None assert ((x - I)*(x - 1)).is_real is None @XFAIL def test_issue_7993(): x = Dummy(integer=True) y = Dummy(noninteger=True) assert (x - y).is_zero is False def test_issue_8075(): raises(InconsistentAssumptions, lambda: Dummy(zero=True, finite=False)) raises(InconsistentAssumptions, lambda: Dummy(zero=True, infinite=True)) def test_issue_8642(): x = Symbol('x', real=True, integer=False) assert (x*2).is_integer is None, (x*2).is_integer def test_issues_8632_8633_8638_8675_8992(): p = Dummy(integer=True, positive=True) nn = Dummy(integer=True, nonnegative=True) assert (p - S.Half).is_positive assert (p - 1).is_nonnegative assert (nn + 1).is_positive assert (-p + 1).is_nonpositive assert (-nn - 1).is_negative prime = Dummy(prime=True) assert (prime - 2).is_nonnegative assert (prime - 3).is_nonnegative is None even = Dummy(positive=True, even=True) assert (even - 2).is_nonnegative p = Dummy(positive=True) assert (p/(p + 1) - 1).is_negative assert ((p + 2)**3 - S.Half).is_positive n = Dummy(negative=True) assert (n - 3).is_nonpositive def test_issue_9115_9150(): n = Dummy('n', integer=True, nonnegative=True) assert (factorial(n) >= 1) == True assert (factorial(n) < 1) == False assert factorial(n + 1).is_even is None assert factorial(n + 2).is_even is True assert factorial(n + 2) >= 2 def test_issue_9165(): z = Symbol('z', zero=True) f = Symbol('f', finite=False) assert 0/z is S.NaN assert 0*(1/z) is S.NaN assert 0*f is S.NaN def test_issue_10024(): x = Dummy('x') assert Mod(x, 2*pi).is_zero is None def test_issue_10302(): x = Symbol('x') r = Symbol('r', real=True) u = -(3*2**pi)**(1/pi) + 2*3**(1/pi) i = u + u*I assert i.is_real is None # w/o simplification this should fail assert (u + i).is_zero is None assert (1 + i).is_zero is False a = Dummy('a', zero=True) assert (a + I).is_zero is False assert (a + r*I).is_zero is None assert (a + I).is_imaginary assert (a + x + I).is_imaginary is None assert (a + r*I + I).is_imaginary is None def test_complex_reciprocal_imaginary(): assert (1 / (4 + 3*I)).is_imaginary is False def test_issue_16313(): x = Symbol('x', extended_real=False) k = Symbol('k', real=True) l = Symbol('l', real=True, zero=False) assert (-x).is_real is False assert (k*x).is_real is None # k can be zero also assert (l*x).is_real is False assert (l*x*x).is_real is None # since x*x can be a real number assert (-x).is_positive is False def test_issue_16579(): # extended_real -> finite | infinite x = Symbol('x', extended_real=True, infinite=False) y = Symbol('y', extended_real=True, finite=False) assert x.is_finite is True assert y.is_infinite is True # With PR 16978, complex now implies finite c = Symbol('c', complex=True) assert c.is_finite is True raises(InconsistentAssumptions, lambda: Dummy(complex=True, finite=False)) # Now infinite == !finite nf = Symbol('nf', finite=False) assert nf.is_infinite is True def test_issue_17556(): z = I*oo assert z.is_imaginary is False assert z.is_finite is False def test_issue_21651(): k = Symbol('k', positive=True, integer=True) exp = 2*2**(-k) assert exp.is_integer is None def test_assumptions_copy(): assert assumptions(Symbol('x'), {"commutative": True} ) == {'commutative': True} assert assumptions(Symbol('x'), ['integer']) == {} assert assumptions(Symbol('x'), ['commutative'] ) == {'commutative': True} assert assumptions(Symbol('x')) == {'commutative': True} assert assumptions(1)['positive'] assert assumptions(3 + I) == { 'algebraic': True, 'commutative': True, 'complex': True, 'composite': False, 'even': False, 'extended_negative': False, 'extended_nonnegative': False, 'extended_nonpositive': False, 'extended_nonzero': False, 'extended_positive': False, 'extended_real': False, 'finite': True, 'imaginary': False, 'infinite': False, 'integer': False, 'irrational': False, 'negative': False, 'noninteger': False, 'nonnegative': False, 'nonpositive': False, 'nonzero': False, 'odd': False, 'positive': False, 'prime': False, 'rational': False, 'real': False, 'transcendental': False, 'zero': False} def test_check_assumptions(): assert check_assumptions(1, 0) is False x = Symbol('x', positive=True) assert check_assumptions(1, x) is True assert check_assumptions(1, 1) is True assert check_assumptions(-1, 1) is False i = Symbol('i', integer=True) # don't know if i is positive (or prime, etc...) assert check_assumptions(i, 1) is None assert check_assumptions(Dummy(integer=None), integer=True) is None assert check_assumptions(Dummy(integer=None), integer=False) is None assert check_assumptions(Dummy(integer=False), integer=True) is False assert check_assumptions(Dummy(integer=True), integer=False) is False # no T/F assumptions to check assert check_assumptions(Dummy(integer=False), integer=None) is True raises(ValueError, lambda: check_assumptions(2*x, x, positive=True)) def test_failing_assumptions(): x = Symbol('x', positive=True) y = Symbol('y') assert failing_assumptions(6*x + y, **x.assumptions0) == \ {'real': None, 'imaginary': None, 'complex': None, 'hermitian': None, 'positive': None, 'nonpositive': None, 'nonnegative': None, 'nonzero': None, 'negative': None, 'zero': None, 'extended_real': None, 'finite': None, 'infinite': None, 'extended_negative': None, 'extended_nonnegative': None, 'extended_nonpositive': None, 'extended_nonzero': None, 'extended_positive': None } def test_common_assumptions(): assert common_assumptions([0, 1, 2] ) == {'algebraic': True, 'irrational': False, 'hermitian': True, 'extended_real': True, 'real': True, 'extended_negative': False, 'extended_nonnegative': True, 'integer': True, 'rational': True, 'imaginary': False, 'complex': True, 'commutative': True,'noninteger': False, 'composite': False, 'infinite': False, 'nonnegative': True, 'finite': True, 'transcendental': False,'negative': False} assert common_assumptions([0, 1, 2], 'positive integer'.split() ) == {'integer': True} assert common_assumptions([0, 1, 2], []) == {} assert common_assumptions([], ['integer']) == {} assert common_assumptions([0], ['integer']) == {'integer': True} def test_pre_generated_assumption_rules_are_valid(): # check the pre-generated assumptions match freshly generated assumptions # if this check fails, consider updating the assumptions # see sympy.core.assumptions._generate_assumption_rules pre_generated_assumptions =_load_pre_generated_assumption_rules() generated_assumptions =_generate_assumption_rules() assert pre_generated_assumptions._to_python() == generated_assumptions._to_python(), "pre-generated assumptions are invalid, see sympy.core.assumptions._generate_assumption_rules" def test_ask_shuffle(): grp = PermutationGroup(Permutation(1, 0, 2), Permutation(2, 1, 3)) seed(123) first = grp.random() seed(123) simplify(I) second = grp.random() seed(123) simplify(-I) third = grp.random() assert first == second == third