from sympy.core.expr import unchanged from sympy.sets import (ConditionSet, Intersection, FiniteSet, EmptySet, Union, Contains, ImageSet) from sympy.sets.sets import SetKind from sympy.core.function import (Function, Lambda) from sympy.core.mod import Mod from sympy.core.kind import NumberKind from sympy.core.numbers import (oo, pi) from sympy.core.relational import (Eq, Ne) from sympy.core.singleton import S from sympy.core.symbol import (Symbol, symbols) from sympy.functions.elementary.complexes import Abs from sympy.functions.elementary.trigonometric import (asin, sin) from sympy.logic.boolalg import And from sympy.matrices.dense import Matrix from sympy.matrices.expressions.matexpr import MatrixSymbol from sympy.sets.sets import Interval from sympy.testing.pytest import raises, warns_deprecated_sympy w = Symbol('w') x = Symbol('x') y = Symbol('y') z = Symbol('z') f = Function('f') def test_CondSet(): sin_sols_principal = ConditionSet(x, Eq(sin(x), 0), Interval(0, 2*pi, False, True)) assert pi in sin_sols_principal assert pi/2 not in sin_sols_principal assert 3*pi not in sin_sols_principal assert oo not in sin_sols_principal assert 5 in ConditionSet(x, x**2 > 4, S.Reals) assert 1 not in ConditionSet(x, x**2 > 4, S.Reals) # in this case, 0 is not part of the base set so # it can't be in any subset selected by the condition assert 0 not in ConditionSet(x, y > 5, Interval(1, 7)) # since 'in' requires a true/false, the following raises # an error because the given value provides no information # for the condition to evaluate (since the condition does # not depend on the dummy symbol): the result is `y > 5`. # In this case, ConditionSet is just acting like # Piecewise((Interval(1, 7), y > 5), (S.EmptySet, True)). raises(TypeError, lambda: 6 in ConditionSet(x, y > 5, Interval(1, 7))) X = MatrixSymbol('X', 2, 2) matrix_set = ConditionSet(X, Eq(X*Matrix([[1, 1], [1, 1]]), X)) Y = Matrix([[0, 0], [0, 0]]) assert matrix_set.contains(Y).doit() is S.true Z = Matrix([[1, 2], [3, 4]]) assert matrix_set.contains(Z).doit() is S.false assert isinstance(ConditionSet(x, x < 1, {x, y}).base_set, FiniteSet) raises(TypeError, lambda: ConditionSet(x, x + 1, {x, y})) raises(TypeError, lambda: ConditionSet(x, x, 1)) I = S.Integers U = S.UniversalSet C = ConditionSet assert C(x, False, I) is S.EmptySet assert C(x, True, I) is I assert C(x, x < 1, C(x, x < 2, I) ) == C(x, (x < 1) & (x < 2), I) assert C(y, y < 1, C(x, y < 2, I) ) == C(x, (x < 1) & (y < 2), I), C(y, y < 1, C(x, y < 2, I)) assert C(y, y < 1, C(x, x < 2, I) ) == C(y, (y < 1) & (y < 2), I) assert C(y, y < 1, C(x, y < x, I) ) == C(x, (x < 1) & (y < x), I) assert unchanged(C, y, x < 1, C(x, y < x, I)) assert ConditionSet(x, x < 1).base_set is U # arg checking is not done at instantiation but this # will raise an error when containment is tested assert ConditionSet((x,), x < 1).base_set is U c = ConditionSet((x, y), x < y, I**2) assert (1, 2) in c assert (1, pi) not in c raises(TypeError, lambda: C(x, x > 1, C((x, y), x > 1, I**2))) # signature mismatch since only 3 args are accepted raises(TypeError, lambda: C((x, y), x + y < 2, U, U)) def test_CondSet_intersect(): input_conditionset = ConditionSet(x, x**2 > 4, Interval(1, 4, False, False)) other_domain = Interval(0, 3, False, False) output_conditionset = ConditionSet(x, x**2 > 4, Interval( 1, 3, False, False)) assert Intersection(input_conditionset, other_domain ) == output_conditionset def test_issue_9849(): assert ConditionSet(x, Eq(x, x), S.Naturals ) is S.Naturals assert ConditionSet(x, Eq(Abs(sin(x)), -1), S.Naturals ) == S.EmptySet def test_simplified_FiniteSet_in_CondSet(): assert ConditionSet(x, And(x < 1, x > -3), FiniteSet(0, 1, 2) ) == FiniteSet(0) assert ConditionSet(x, x < 0, FiniteSet(0, 1, 2)) == EmptySet assert ConditionSet(x, And(x < -3), EmptySet) == EmptySet y = Symbol('y') assert (ConditionSet(x, And(x > 0), FiniteSet(-1, 0, 1, y)) == Union(FiniteSet(1), ConditionSet(x, And(x > 0), FiniteSet(y)))) assert (ConditionSet(x, Eq(Mod(x, 3), 1), FiniteSet(1, 4, 2, y)) == Union(FiniteSet(1, 4), ConditionSet(x, Eq(Mod(x, 3), 1), FiniteSet(y)))) def test_free_symbols(): assert ConditionSet(x, Eq(y, 0), FiniteSet(z) ).free_symbols == {y, z} assert ConditionSet(x, Eq(x, 0), FiniteSet(z) ).free_symbols == {z} assert ConditionSet(x, Eq(x, 0), FiniteSet(x, z) ).free_symbols == {x, z} assert ConditionSet(x, Eq(x, 0), ImageSet(Lambda(y, y**2), S.Integers)).free_symbols == set() def test_bound_symbols(): assert ConditionSet(x, Eq(y, 0), FiniteSet(z) ).bound_symbols == [x] assert ConditionSet(x, Eq(x, 0), FiniteSet(x, y) ).bound_symbols == [x] assert ConditionSet(x, x < 10, ImageSet(Lambda(y, y**2), S.Integers) ).bound_symbols == [x] assert ConditionSet(x, x < 10, ConditionSet(y, y > 1, S.Integers) ).bound_symbols == [x] def test_as_dummy(): _0, _1 = symbols('_0 _1') assert ConditionSet(x, x < 1, Interval(y, oo) ).as_dummy() == ConditionSet(_0, _0 < 1, Interval(y, oo)) assert ConditionSet(x, x < 1, Interval(x, oo) ).as_dummy() == ConditionSet(_0, _0 < 1, Interval(x, oo)) assert ConditionSet(x, x < 1, ImageSet(Lambda(y, y**2), S.Integers) ).as_dummy() == ConditionSet( _0, _0 < 1, ImageSet(Lambda(_0, _0**2), S.Integers)) e = ConditionSet((x, y), x <= y, S.Reals**2) assert e.bound_symbols == [x, y] assert e.as_dummy() == ConditionSet((_0, _1), _0 <= _1, S.Reals**2) assert e.as_dummy() == ConditionSet((y, x), y <= x, S.Reals**2 ).as_dummy() def test_subs_CondSet(): s = FiniteSet(z, y) c = ConditionSet(x, x < 2, s) assert c.subs(x, y) == c assert c.subs(z, y) == ConditionSet(x, x < 2, FiniteSet(y)) assert c.xreplace({x: y}) == ConditionSet(y, y < 2, s) assert ConditionSet(x, x < y, s ).subs(y, w) == ConditionSet(x, x < w, s.subs(y, w)) # if the user uses assumptions that cause the condition # to evaluate, that can't be helped from SymPy's end n = Symbol('n', negative=True) assert ConditionSet(n, 0 < n, S.Integers) is S.EmptySet p = Symbol('p', positive=True) assert ConditionSet(n, n < y, S.Integers ).subs(n, x) == ConditionSet(n, n < y, S.Integers) raises(ValueError, lambda: ConditionSet( x + 1, x < 1, S.Integers)) assert ConditionSet( p, n < x, Interval(-5, 5)).subs(x, p) == Interval(-5, 5), ConditionSet( p, n < x, Interval(-5, 5)).subs(x, p) assert ConditionSet( n, n < x, Interval(-oo, 0)).subs(x, p ) == Interval(-oo, 0) assert ConditionSet(f(x), f(x) < 1, {w, z} ).subs(f(x), y) == ConditionSet(f(x), f(x) < 1, {w, z}) # issue 17341 k = Symbol('k') img1 = ImageSet(Lambda(k, 2*k*pi + asin(y)), S.Integers) img2 = ImageSet(Lambda(k, 2*k*pi + asin(S.One/3)), S.Integers) assert ConditionSet(x, Contains( y, Interval(-1,1)), img1).subs(y, S.One/3).dummy_eq(img2) assert (0, 1) in ConditionSet((x, y), x + y < 3, S.Integers**2) raises(TypeError, lambda: ConditionSet(n, n < -10, Interval(0, 10))) def test_subs_CondSet_tebr(): with warns_deprecated_sympy(): assert ConditionSet((x, y), {x + 1, x + y}, S.Reals**2) == \ ConditionSet((x, y), Eq(x + 1, 0) & Eq(x + y, 0), S.Reals**2) def test_dummy_eq(): C = ConditionSet I = S.Integers c = C(x, x < 1, I) assert c.dummy_eq(C(y, y < 1, I)) assert c.dummy_eq(1) == False assert c.dummy_eq(C(x, x < 1, S.Reals)) == False c1 = ConditionSet((x, y), Eq(x + 1, 0) & Eq(x + y, 0), S.Reals**2) c2 = ConditionSet((x, y), Eq(x + 1, 0) & Eq(x + y, 0), S.Reals**2) c3 = ConditionSet((x, y), Eq(x + 1, 0) & Eq(x + y, 0), S.Complexes**2) assert c1.dummy_eq(c2) assert c1.dummy_eq(c3) is False assert c.dummy_eq(c1) is False assert c1.dummy_eq(c) is False # issue 19496 m = Symbol('m') n = Symbol('n') a = Symbol('a') d1 = ImageSet(Lambda(m, m*pi), S.Integers) d2 = ImageSet(Lambda(n, n*pi), S.Integers) c1 = ConditionSet(x, Ne(a, 0), d1) c2 = ConditionSet(x, Ne(a, 0), d2) assert c1.dummy_eq(c2) def test_contains(): assert 6 in ConditionSet(x, x > 5, Interval(1, 7)) assert (8 in ConditionSet(x, y > 5, Interval(1, 7))) is False # `in` should give True or False; in this case there is not # enough information for that result raises(TypeError, lambda: 6 in ConditionSet(x, y > 5, Interval(1, 7))) # here, there is enough information but the comparison is # not defined raises(TypeError, lambda: 0 in ConditionSet(x, 1/x >= 0, S.Reals)) assert ConditionSet(x, y > 5, Interval(1, 7) ).contains(6) == (y > 5) assert ConditionSet(x, y > 5, Interval(1, 7) ).contains(8) is S.false assert ConditionSet(x, y > 5, Interval(1, 7) ).contains(w) == And(Contains(w, Interval(1, 7)), y > 5) # This returns an unevaluated Contains object # because 1/0 should not be defined for 1 and 0 in the context of # reals. assert ConditionSet(x, 1/x >= 0, S.Reals).contains(0) == \ Contains(0, ConditionSet(x, 1/x >= 0, S.Reals), evaluate=False) c = ConditionSet((x, y), x + y > 1, S.Integers**2) assert not c.contains(1) assert c.contains((2, 1)) assert not c.contains((0, 1)) c = ConditionSet((w, (x, y)), w + x + y > 1, S.Integers*S.Integers**2) assert not c.contains(1) assert not c.contains((1, 2)) assert not c.contains(((1, 2), 3)) assert not c.contains(((1, 2), (3, 4))) assert c.contains((1, (3, 4))) def test_as_relational(): assert ConditionSet((x, y), x > 1, S.Integers**2).as_relational((x, y) ) == (x > 1) & Contains((x, y), S.Integers**2) assert ConditionSet(x, x > 1, S.Integers).as_relational(x ) == Contains(x, S.Integers) & (x > 1) def test_flatten(): """Tests whether there is basic denesting functionality""" inner = ConditionSet(x, sin(x) + x > 0) outer = ConditionSet(x, Contains(x, inner), S.Reals) assert outer == ConditionSet(x, sin(x) + x > 0, S.Reals) inner = ConditionSet(y, sin(y) + y > 0) outer = ConditionSet(x, Contains(y, inner), S.Reals) assert outer != ConditionSet(x, sin(x) + x > 0, S.Reals) inner = ConditionSet(x, sin(x) + x > 0).intersect(Interval(-1, 1)) outer = ConditionSet(x, Contains(x, inner), S.Reals) assert outer == ConditionSet(x, sin(x) + x > 0, Interval(-1, 1)) def test_duplicate(): from sympy.core.function import BadSignatureError # test coverage for line 95 in conditionset.py, check for duplicates in symbols dup = symbols('a,a') raises(BadSignatureError, lambda: ConditionSet(dup, x < 0)) def test_SetKind_ConditionSet(): assert ConditionSet(x, Eq(sin(x), 0), Interval(0, 2*pi)).kind is SetKind(NumberKind) assert ConditionSet(x, x < 0).kind is SetKind(NumberKind)