def test_intersect(): x = Symbol('x') assert Interval(0, 2).intersect(Interval(1, 2)) == Interval(1, 2) assert Interval(0, 2).intersect(Interval(1, 2, True)) == \ Interval(1, 2, True) assert Interval(0, 2, True).intersect(Interval(1, 2)) == \ Interval(1, 2, False, False) assert Interval(0, 2, True, True).intersect(Interval(1, 2)) == \ Interval(1, 2, False, True) assert Interval(0, 2).intersect(Union(Interval(0, 1), Interval(2, 3))) == \ Union(Interval(0, 1), Interval(2, 2)) assert FiniteSet(1, 2, x).intersect(FiniteSet(x)) == FiniteSet(x) assert FiniteSet('ham', 'eggs').intersect(FiniteSet('ham')) == \ FiniteSet('ham') assert FiniteSet(1, 2, 3, 4, 5).intersect(S.EmptySet) == S.EmptySet assert Interval(0, 5).intersect(FiniteSet(1, 3)) == FiniteSet(1, 3) assert Interval(0, 1, True, True).intersect(FiniteSet(1)) == S.EmptySet assert Union(Interval(0, 1), Interval(2, 3)).intersect(Interval(1, 2)) == \ Union(Interval(1, 1), Interval(2, 2)) assert Union(Interval(0, 1), Interval(2, 3)).intersect(Interval(0, 2)) == \ Union(Interval(0, 1), Interval(2, 2)) assert Union(Interval(0, 1), Interval(2, 3)).intersect(Interval(1, 2, True, True)) == \ S.EmptySet assert Union(Interval(0, 1), Interval(2, 3)).intersect(S.EmptySet) == \ S.EmptySet assert Union(Interval(0, 5), FiniteSet('ham')).intersect(FiniteSet(2, 3, 4, 5, 6)) == \ FiniteSet(2, 3, 4, 5) # tests for the intersection alias assert Interval(0, 5).intersection(FiniteSet(1, 3)) == FiniteSet(1, 3) assert Interval(0, 1, True, True).intersection(FiniteSet(1)) == S.EmptySet assert Union(Interval(0, 1), Interval(2, 3)).intersection(Interval(1, 2)) == \ Union(Interval(1, 1), Interval(2, 2))
def test_boundary_ProductSet_line(): line_in_r2 = Interval(0, 1) * FiniteSet(0) assert line_in_r2.boundary == line_in_r2
def test_is_closed(): assert Interval(0, 1, False, False).is_closed assert not Interval(0, 1, True, False).is_closed assert FiniteSet(1, 2, 3).is_closed
def test_issue_5724_7680(): assert I not in S.Reals # issue 7680 assert Interval(-oo, oo).contains(I) is S.false
def test_boundary_Union(): assert (Interval(0, 1) + Interval(2, 3)).boundary == FiniteSet(0, 1, 2, 3) assert ((Interval(0, 1, False, True) + Interval(1, 2, True, False)).boundary == FiniteSet(0, 1, 2)) assert (Interval(0, 1) + FiniteSet(2)).boundary == FiniteSet(0, 1, 2) assert Union(Interval(0, 10), Interval(5, 15), evaluate=False).boundary \ == FiniteSet(0, 15) assert Union(Interval(0, 10), Interval(0, 1), evaluate=False).boundary \ == FiniteSet(0, 10) assert Union(Interval(0, 10, True, True), Interval(10, 15, True, True), evaluate=False).boundary \ == FiniteSet(0, 10, 15)
def test_Interval_free_symbols(): # issue 6211 assert Interval(0, 1).free_symbols == set() x = Symbol('x', real=True) assert Interval(0, x).free_symbols == set([x])
def test_image_Intersection(): x = Symbol('x', real=True) y = Symbol('y', real=True) assert imageset(x, x**2, Interval(-2, 0).intersect(Interval(x, y))) == \ Interval(0, 4).intersect(Interval(Min(x**2, y**2), Max(x**2, y**2)))
def test_is_superset(): assert Interval(0, 1).is_superset(Interval(0, 2)) == False assert Interval(0, 3).is_superset(Interval(0, 2)) assert FiniteSet(1, 2).is_superset(FiniteSet(1, 2, 3, 4)) == False assert FiniteSet(4, 5).is_superset(FiniteSet(1, 2, 3, 4)) == False assert FiniteSet(1).is_superset(Interval(0, 2)) == False assert FiniteSet(1, 2).is_superset(Interval(0, 2, True, True)) == False assert (Interval(1, 2) + FiniteSet(3)).is_superset( (Interval(0, 2, False, True) + FiniteSet(2, 3))) == False assert Interval(3, 4).is_superset(Union(Interval(0, 1), Interval(2, 5))) == False assert FiniteSet(1, 2, 3, 4).is_superset(Interval(0, 5)) == False assert S.EmptySet.is_superset(FiniteSet(1, 2, 3)) == False assert Interval(0, 1).is_superset(S.EmptySet) == True assert S.EmptySet.is_superset(S.EmptySet) == True raises(ValueError, lambda: S.EmptySet.is_superset(1)) # tests for the issuperset alias assert Interval(0, 1).issuperset(S.EmptySet) == True assert S.EmptySet.issuperset(S.EmptySet) == True
def test_is_proper_superset(): assert Interval(0, 1).is_proper_superset(Interval(0, 2)) is False assert Interval(0, 3).is_proper_superset(Interval(0, 2)) is True assert FiniteSet(1, 2, 3).is_proper_superset(S.EmptySet) is True raises(ValueError, lambda: Interval(0, 1).is_proper_superset(0))
def test_interval_to_mpi(): assert Interval(0, 1).to_mpi() == mpi(0, 1) assert Interval(0, 1, True, False).to_mpi() == mpi(0, 1) assert type(Interval(0, 1).to_mpi()) == type(mpi(0, 1))
def test_measure(): a = Symbol('a', real=True) assert Interval(1, 3).measure == 2 assert Interval(0, a).measure == a assert Interval(1, a).measure == a - 1 assert Union(Interval(1, 2), Interval(3, 4)).measure == 2 assert Union(Interval(1, 2), Interval(3, 4), FiniteSet(5, 6, 7)).measure \ == 2 assert FiniteSet(1, 2, oo, a, -oo, -5).measure == 0 assert S.EmptySet.measure == 0 square = Interval(0, 10) * Interval(0, 10) offsetsquare = Interval(5, 15) * Interval(5, 15) band = Interval(-oo, oo) * Interval(2, 4) assert square.measure == offsetsquare.measure == 100 assert (square + offsetsquare).measure == 175 # there is some overlap assert (square - offsetsquare).measure == 75 assert (square * FiniteSet(1, 2, 3)).measure == 0 assert (square.intersect(band)).measure == 20 assert (square + band).measure == oo assert (band * FiniteSet(1, 2, 3)).measure == nan
def test_interval_subs(): a = Symbol('a', real=True) assert Interval(0, a).subs(a, 2) == Interval(0, 2) assert Interval(a, 0).subs(a, 2) == S.EmptySet
def test_ProductSet_of_single_arg_is_arg(): assert ProductSet(Interval(0, 1)) == Interval(0, 1)
def test_is_disjoint(): assert Interval(0, 2).is_disjoint(Interval(1, 2)) == False assert Interval(0, 2).is_disjoint(Interval(3, 4)) == True
def test_product_basic(): H, T = 'H', 'T' unit_line = Interval(0, 1) d6 = FiniteSet(1, 2, 3, 4, 5, 6) d4 = FiniteSet(1, 2, 3, 4) coin = FiniteSet(H, T) square = unit_line * unit_line assert (0, 0) in square assert 0 not in square assert (H, T) in coin ** 2 assert (.5, .5, .5) in square * unit_line assert (H, 3, 3) in coin * d6* d6 HH, TT = sympify(H), sympify(T) assert set(coin**2) == set(((HH, HH), (HH, TT), (TT, HH), (TT, TT))) assert (d4*d4).is_subset(d6*d6) assert square.complement(Interval(-oo, oo)*Interval(-oo, oo)) == Union( (Interval(-oo, 0, True, True) + Interval(1, oo, True, True))*Interval(-oo, oo), Interval(-oo, oo)*(Interval(-oo, 0, True, True) + Interval(1, oo, True, True))) assert (Interval(-5, 5)**3).is_subset(Interval(-10, 10)**3) assert not (Interval(-10, 10)**3).is_subset(Interval(-5, 5)**3) assert not (Interval(-5, 5)**2).is_subset(Interval(-10, 10)**3) assert (Interval(.2, .5)*FiniteSet(.5)).is_subset(square) # segment in square assert len(coin*coin*coin) == 8 assert len(S.EmptySet*S.EmptySet) == 0 assert len(S.EmptySet*coin) == 0 raises(TypeError, lambda: len(coin*Interval(0, 2)))
def test_contains(): assert Interval(0, 2).contains(1) is S.true assert Interval(0, 2).contains(3) is S.false assert Interval(0, 2, True, False).contains(0) is S.false assert Interval(0, 2, True, False).contains(2) is S.true assert Interval(0, 2, False, True).contains(0) is S.true assert Interval(0, 2, False, True).contains(2) is S.false assert Interval(0, 2, True, True).contains(0) is S.false assert Interval(0, 2, True, True).contains(2) is S.false assert FiniteSet(1, 2, 3).contains(2) is S.true assert FiniteSet(1, 2, Symbol('x')).contains(Symbol('x')) is S.true items = [1, 2, S.Infinity, S('ham'), -1.1] fset = FiniteSet(*items) assert all(item in fset for item in items) assert all(fset.contains(item) is S.true for item in items) assert Union(Interval(0, 1), Interval(2, 5)).contains(3) is S.true assert Union(Interval(0, 1), Interval(2, 5)).contains(6) is S.false assert Union(Interval(0, 1), FiniteSet(2, 5)).contains(3) is S.false assert S.EmptySet.contains(1) is S.false
def test_Union_of_ProductSets_shares(): line = Interval(0, 2) points = FiniteSet(0, 1, 2) assert Union(line * line, line * points) == line * line
def test_is_number(): assert Interval(0, 1).is_number is False assert Set().is_number is False
def test_image_interval(): from sympy.core.numbers import Rational x = Symbol('x', real=True) a = Symbol('a', real=True) assert imageset(x, 2*x, Interval(-2, 1)) == Interval(-4, 2) assert imageset(x, 2*x, Interval(-2, 1, True, False)) == \ Interval(-4, 2, True, False) assert imageset(x, x**2, Interval(-2, 1, True, False)) == \ Interval(0, 4, False, True) assert imageset(x, x**2, Interval(-2, 1)) == Interval(0, 4) assert imageset(x, x**2, Interval(-2, 1, True, False)) == \ Interval(0, 4, False, True) assert imageset(x, x**2, Interval(-2, 1, True, True)) == \ Interval(0, 4, False, True) assert imageset(x, (x - 2)**2, Interval(1, 3)) == Interval(0, 1) assert imageset(x, 3*x**4 - 26*x**3 + 78*x**2 - 90*x, Interval(0, 4)) == \ Interval(-35, 0) # Multiple Maxima assert imageset(x, x + 1/x, Interval(-oo, oo)) == Interval(-oo, -2) \ + Interval(2, oo) # Single Infinite discontinuity assert imageset(x, 1/x + 1/(x-1)**2, Interval(0, 2, True, False)) == \ Interval(Rational(3, 2), oo, False) # Multiple Infinite discontinuities # Test for Python lambda assert imageset(lambda x: 2*x, Interval(-2, 1)) == Interval(-4, 2) assert imageset(Lambda(x, a*x), Interval(0, 1)) == \ ImageSet(Lambda(x, a*x), Interval(0, 1)) assert imageset(Lambda(x, sin(cos(x))), Interval(0, 1)) == \ ImageSet(Lambda(x, sin(cos(x))), Interval(0, 1))
def test_Interval_is_left_unbounded(): assert Interval(3, 4).is_left_unbounded is False assert Interval(-oo, 3).is_left_unbounded is True assert Interval(Float("-inf"), 3).is_left_unbounded is True
def test_image_Union(): x = Symbol('x', real=True) assert imageset(x, x**2, Interval(-2, 0) + FiniteSet(1, 2, 3)) == \ (Interval(0, 4) + FiniteSet(9))
def test_Interval_is_right_unbounded(): assert Interval(3, 4).is_right_unbounded is False assert Interval(3, oo).is_right_unbounded is True assert Interval(3, Float("+inf")).is_right_unbounded is True
def test_boundary(): x = Symbol('x', real=True) y = Symbol('y', real=True) assert FiniteSet(1).boundary == FiniteSet(1) assert all(Interval(0, 1, left_open, right_open).boundary == FiniteSet(0, 1) for left_open in (true, false) for right_open in (true, false))
def test_union(): assert Union(Interval(1, 2), Interval(2, 3)) == Interval(1, 3) assert Union(Interval(1, 2), Interval(2, 3, True)) == Interval(1, 3) assert Union(Interval(1, 3), Interval(2, 4)) == Interval(1, 4) assert Union(Interval(1, 2), Interval(1, 3)) == Interval(1, 3) assert Union(Interval(1, 3), Interval(1, 2)) == Interval(1, 3) assert Union(Interval(1, 3, False, True), Interval(1, 2)) == \ Interval(1, 3, False, True) assert Union(Interval(1, 3), Interval(1, 2, False, True)) == Interval(1, 3) assert Union(Interval(1, 2, True), Interval(1, 3)) == Interval(1, 3) assert Union(Interval(1, 2, True), Interval(1, 3, True)) == \ Interval(1, 3, True) assert Union(Interval(1, 2, True), Interval(1, 3, True, True)) == \ Interval(1, 3, True, True) assert Union(Interval(1, 2, True, True), Interval(1, 3, True)) == \ Interval(1, 3, True) assert Union(Interval(1, 3), Interval(2, 3)) == Interval(1, 3) assert Union(Interval(1, 3, False, True), Interval(2, 3)) == \ Interval(1, 3) assert Union(Interval(1, 2, False, True), Interval(2, 3, True)) != \ Interval(1, 3) assert Union(Interval(1, 2), S.EmptySet) == Interval(1, 2) assert Union(S.EmptySet) == S.EmptySet assert Union(Interval(0, 1), [FiniteSet(1.0/n) for n in range(1, 10)]) == \ Interval(0, 1) assert Interval(1, 2).union(Interval(2, 3)) == \ Interval(1, 2) + Interval(2, 3) assert Interval(1, 2).union(Interval(2, 3)) == Interval(1, 3) assert Union(Set()) == Set() assert FiniteSet(1) + FiniteSet(2) + FiniteSet(3) == FiniteSet(1, 2, 3) assert FiniteSet('ham') + FiniteSet('eggs') == FiniteSet('ham', 'eggs') assert FiniteSet(1, 2, 3) + S.EmptySet == FiniteSet(1, 2, 3) assert FiniteSet(1, 2, 3) & FiniteSet(2, 3, 4) == FiniteSet(2, 3) assert FiniteSet(1, 2, 3) | FiniteSet(2, 3, 4) == FiniteSet(1, 2, 3, 4) x = Symbol("x") y = Symbol("y") z = Symbol("z") assert S.EmptySet | FiniteSet(x, FiniteSet(y, z)) == \ FiniteSet(x, FiniteSet(y, z)) # Test that Intervals and FiniteSets play nicely assert Interval(1, 3) + FiniteSet(2) == Interval(1, 3) assert Interval(1, 3, True, True) + FiniteSet(3) == \ Interval(1, 3, True, False) X = Interval(1, 3) + FiniteSet(5) Y = Interval(1, 2) + FiniteSet(3) XandY = X.intersect(Y) assert 2 in X and 3 in X and 3 in XandY assert XandY.is_subset(X) and XandY.is_subset(Y) raises(TypeError, lambda: Union(1, 2, 3)) assert X.is_iterable is False # issue 7843 assert Union(S.EmptySet, FiniteSet(-sqrt(-I), sqrt(-I))) == FiniteSet(-sqrt(-I), sqrt(-I))
def test_union_boundary_of_joining_sets(): """ Testing the boundary of unions is a hard problem """ assert Union(Interval(0, 10), Interval(10, 15), evaluate=False).boundary \ == FiniteSet(0, 15)
def test_Union_as_relational(): x = Symbol('x') assert (Interval(0, 1) + FiniteSet(2)).as_relational(x) == \ Or(And(Le(0, x), Le(x, 1)), Eq(x, 2)) assert (Interval(0, 1, True, True) + FiniteSet(1)).as_relational(x) == \ And(Lt(0, x), Le(x, 1))
def test_is_open(): assert not Interval(0, 1, False, False).is_open assert not Interval(0, 1, True, False).is_open assert Interval(0, 1, True, True).is_open assert not FiniteSet(1, 2, 3).is_open
def test_Intersection_as_relational(): x = Symbol('x') assert (Intersection(Interval(0, 1), FiniteSet(2), evaluate=False).as_relational(x) == And(And(Le(0, x), Le(x, 1)), Eq(x, 2)))
def test_closure(): assert Interval(0, 1, False, True).closure == Interval(0, 1, False, False)
def test_complement(): assert Interval(0, 1).complement(S.Reals) == \ Union(Interval(-oo, 0, True, True), Interval(1, oo, True, True)) assert Interval(0, 1, True, False).complement(S.Reals) == \ Union(Interval(-oo, 0, True, False), Interval(1, oo, True, True)) assert Interval(0, 1, False, True).complement(S.Reals) == \ Union(Interval(-oo, 0, True, True), Interval(1, oo, False, True)) assert Interval(0, 1, True, True).complement(S.Reals) == \ Union(Interval(-oo, 0, True, False), Interval(1, oo, False, True)) assert S.UniversalSet.complement(S.EmptySet) == S.EmptySet assert S.UniversalSet.complement(S.Reals) == S.EmptySet assert S.UniversalSet.complement(S.UniversalSet) == S.EmptySet assert Union(Interval(0, 1), Interval(2, 3)).complement(S.Reals) == \ Union(Interval(-oo, 0, True, True), Interval(1, 2, True, True), Interval(3, oo, True, True)) assert FiniteSet(0).complement(S.Reals) == \ Union(Interval(-oo, 0, True, True), Interval(0, oo, True, True)) assert (FiniteSet(5) + Interval(S.NegativeInfinity, 0)).complement(S.Reals) == \ Interval(0, 5, True, True) + Interval(5, S.Infinity, True, True) assert FiniteSet(1, 2, 3).complement(S.Reals) == \ Interval(S.NegativeInfinity, 1, True, True) + \ Interval(1, 2, True, True) + Interval(2, 3, True, True) +\ Interval(3, S.Infinity, True, True) assert FiniteSet(x).complement(S.Reals) == Complement(S.Reals, FiniteSet(x)) assert FiniteSet(0, x).complement(S.Reals) == Complement(Interval(-oo, 0, True, True) + Interval(0, oo, True, True) ,FiniteSet(x), evaluate=False) square = Interval(0, 1) * Interval(0, 1) notsquare = square.complement(S.Reals*S.Reals) assert all(pt in square for pt in [(0, 0), (.5, .5), (1, 0), (1, 1)]) assert not any( pt in notsquare for pt in [(0, 0), (.5, .5), (1, 0), (1, 1)]) assert not any(pt in square for pt in [(-1, 0), (1.5, .5), (10, 10)]) assert all(pt in notsquare for pt in [(-1, 0), (1.5, .5), (10, 10)])