Traktor/myenv/Lib/site-packages/sympy/sets/tests/test_fancysets.py
2024-05-23 01:57:24 +02:00

1307 lines
50 KiB
Python

from sympy.core.expr import unchanged
from sympy.sets.contains import Contains
from sympy.sets.fancysets import (ImageSet, Range, normalize_theta_set,
ComplexRegion)
from sympy.sets.sets import (FiniteSet, Interval, Union, imageset,
Intersection, ProductSet, SetKind)
from sympy.sets.conditionset import ConditionSet
from sympy.simplify.simplify import simplify
from sympy.core.basic import Basic
from sympy.core.containers import Tuple, TupleKind
from sympy.core.function import Lambda
from sympy.core.kind import NumberKind
from sympy.core.numbers import (I, Rational, oo, pi)
from sympy.core.relational import Eq
from sympy.core.singleton import S
from sympy.core.symbol import (Dummy, Symbol, symbols)
from sympy.functions.elementary.complexes import Abs
from sympy.functions.elementary.exponential import (exp, log)
from sympy.functions.elementary.integers import floor
from sympy.functions.elementary.miscellaneous import sqrt
from sympy.functions.elementary.trigonometric import (cos, sin, tan)
from sympy.logic.boolalg import And
from sympy.matrices.dense import eye
from sympy.testing.pytest import XFAIL, raises
from sympy.abc import x, y, t, z
from sympy.core.mod import Mod
import itertools
def test_naturals():
N = S.Naturals
assert 5 in N
assert -5 not in N
assert 5.5 not in N
ni = iter(N)
a, b, c, d = next(ni), next(ni), next(ni), next(ni)
assert (a, b, c, d) == (1, 2, 3, 4)
assert isinstance(a, Basic)
assert N.intersect(Interval(-5, 5)) == Range(1, 6)
assert N.intersect(Interval(-5, 5, True, True)) == Range(1, 5)
assert N.boundary == N
assert N.is_open == False
assert N.is_closed == True
assert N.inf == 1
assert N.sup is oo
assert not N.contains(oo)
for s in (S.Naturals0, S.Naturals):
assert s.intersection(S.Reals) is s
assert s.is_subset(S.Reals)
assert N.as_relational(x) == And(Eq(floor(x), x), x >= 1, x < oo)
def test_naturals0():
N = S.Naturals0
assert 0 in N
assert -1 not in N
assert next(iter(N)) == 0
assert not N.contains(oo)
assert N.contains(sin(x)) == Contains(sin(x), N)
def test_integers():
Z = S.Integers
assert 5 in Z
assert -5 in Z
assert 5.5 not in Z
assert not Z.contains(oo)
assert not Z.contains(-oo)
zi = iter(Z)
a, b, c, d = next(zi), next(zi), next(zi), next(zi)
assert (a, b, c, d) == (0, 1, -1, 2)
assert isinstance(a, Basic)
assert Z.intersect(Interval(-5, 5)) == Range(-5, 6)
assert Z.intersect(Interval(-5, 5, True, True)) == Range(-4, 5)
assert Z.intersect(Interval(5, S.Infinity)) == Range(5, S.Infinity)
assert Z.intersect(Interval.Lopen(5, S.Infinity)) == Range(6, S.Infinity)
assert Z.inf is -oo
assert Z.sup is oo
assert Z.boundary == Z
assert Z.is_open == False
assert Z.is_closed == True
assert Z.as_relational(x) == And(Eq(floor(x), x), -oo < x, x < oo)
def test_ImageSet():
raises(ValueError, lambda: ImageSet(x, S.Integers))
assert ImageSet(Lambda(x, 1), S.Integers) == FiniteSet(1)
assert ImageSet(Lambda(x, y), S.Integers) == {y}
assert ImageSet(Lambda(x, 1), S.EmptySet) == S.EmptySet
empty = Intersection(FiniteSet(log(2)/pi), S.Integers)
assert unchanged(ImageSet, Lambda(x, 1), empty) # issue #17471
squares = ImageSet(Lambda(x, x**2), S.Naturals)
assert 4 in squares
assert 5 not in squares
assert FiniteSet(*range(10)).intersect(squares) == FiniteSet(1, 4, 9)
assert 16 not in squares.intersect(Interval(0, 10))
si = iter(squares)
a, b, c, d = next(si), next(si), next(si), next(si)
assert (a, b, c, d) == (1, 4, 9, 16)
harmonics = ImageSet(Lambda(x, 1/x), S.Naturals)
assert Rational(1, 5) in harmonics
assert Rational(.25) in harmonics
assert 0.25 not in harmonics
assert Rational(.3) not in harmonics
assert (1, 2) not in harmonics
assert harmonics.is_iterable
assert imageset(x, -x, Interval(0, 1)) == Interval(-1, 0)
assert ImageSet(Lambda(x, x**2), Interval(0, 2)).doit() == Interval(0, 4)
assert ImageSet(Lambda((x, y), 2*x), {4}, {3}).doit() == FiniteSet(8)
assert (ImageSet(Lambda((x, y), x+y), {1, 2, 3}, {10, 20, 30}).doit() ==
FiniteSet(11, 12, 13, 21, 22, 23, 31, 32, 33))
c = Interval(1, 3) * Interval(1, 3)
assert Tuple(2, 6) in ImageSet(Lambda(((x, y),), (x, 2*y)), c)
assert Tuple(2, S.Half) in ImageSet(Lambda(((x, y),), (x, 1/y)), c)
assert Tuple(2, -2) not in ImageSet(Lambda(((x, y),), (x, y**2)), c)
assert Tuple(2, -2) in ImageSet(Lambda(((x, y),), (x, -2)), c)
c3 = ProductSet(Interval(3, 7), Interval(8, 11), Interval(5, 9))
assert Tuple(8, 3, 9) in ImageSet(Lambda(((t, y, x),), (y, t, x)), c3)
assert Tuple(Rational(1, 8), 3, 9) in ImageSet(Lambda(((t, y, x),), (1/y, t, x)), c3)
assert 2/pi not in ImageSet(Lambda(((x, y),), 2/x), c)
assert 2/S(100) not in ImageSet(Lambda(((x, y),), 2/x), c)
assert Rational(2, 3) in ImageSet(Lambda(((x, y),), 2/x), c)
S1 = imageset(lambda x, y: x + y, S.Integers, S.Naturals)
assert S1.base_pset == ProductSet(S.Integers, S.Naturals)
assert S1.base_sets == (S.Integers, S.Naturals)
# Passing a set instead of a FiniteSet shouldn't raise
assert unchanged(ImageSet, Lambda(x, x**2), {1, 2, 3})
S2 = ImageSet(Lambda(((x, y),), x+y), {(1, 2), (3, 4)})
assert 3 in S2.doit()
# FIXME: This doesn't yet work:
#assert 3 in S2
assert S2._contains(3) is None
raises(TypeError, lambda: ImageSet(Lambda(x, x**2), 1))
def test_image_is_ImageSet():
assert isinstance(imageset(x, sqrt(sin(x)), Range(5)), ImageSet)
def test_halfcircle():
r, th = symbols('r, theta', real=True)
L = Lambda(((r, th),), (r*cos(th), r*sin(th)))
halfcircle = ImageSet(L, Interval(0, 1)*Interval(0, pi))
assert (1, 0) in halfcircle
assert (0, -1) not in halfcircle
assert (0, 0) in halfcircle
assert halfcircle._contains((r, 0)) is None
# This one doesn't work:
#assert (r, 2*pi) not in halfcircle
assert not halfcircle.is_iterable
def test_ImageSet_iterator_not_injective():
L = Lambda(x, x - x % 2) # produces 0, 2, 2, 4, 4, 6, 6, ...
evens = ImageSet(L, S.Naturals)
i = iter(evens)
# No repeats here
assert (next(i), next(i), next(i), next(i)) == (0, 2, 4, 6)
def test_inf_Range_len():
raises(ValueError, lambda: len(Range(0, oo, 2)))
assert Range(0, oo, 2).size is S.Infinity
assert Range(0, -oo, -2).size is S.Infinity
assert Range(oo, 0, -2).size is S.Infinity
assert Range(-oo, 0, 2).size is S.Infinity
def test_Range_set():
empty = Range(0)
assert Range(5) == Range(0, 5) == Range(0, 5, 1)
r = Range(10, 20, 2)
assert 12 in r
assert 8 not in r
assert 11 not in r
assert 30 not in r
assert list(Range(0, 5)) == list(range(5))
assert list(Range(5, 0, -1)) == list(range(5, 0, -1))
assert Range(5, 15).sup == 14
assert Range(5, 15).inf == 5
assert Range(15, 5, -1).sup == 15
assert Range(15, 5, -1).inf == 6
assert Range(10, 67, 10).sup == 60
assert Range(60, 7, -10).inf == 10
assert len(Range(10, 38, 10)) == 3
assert Range(0, 0, 5) == empty
assert Range(oo, oo, 1) == empty
assert Range(oo, 1, 1) == empty
assert Range(-oo, 1, -1) == empty
assert Range(1, oo, -1) == empty
assert Range(1, -oo, 1) == empty
assert Range(1, -4, oo) == empty
ip = symbols('ip', positive=True)
assert Range(0, ip, -1) == empty
assert Range(0, -ip, 1) == empty
assert Range(1, -4, -oo) == Range(1, 2)
assert Range(1, 4, oo) == Range(1, 2)
assert Range(-oo, oo).size == oo
assert Range(oo, -oo, -1).size == oo
raises(ValueError, lambda: Range(-oo, oo, 2))
raises(ValueError, lambda: Range(x, pi, y))
raises(ValueError, lambda: Range(x, y, 0))
assert 5 in Range(0, oo, 5)
assert -5 in Range(-oo, 0, 5)
assert oo not in Range(0, oo)
ni = symbols('ni', integer=False)
assert ni not in Range(oo)
u = symbols('u', integer=None)
assert Range(oo).contains(u) is not False
inf = symbols('inf', infinite=True)
assert inf not in Range(-oo, oo)
raises(ValueError, lambda: Range(0, oo, 2)[-1])
raises(ValueError, lambda: Range(0, -oo, -2)[-1])
assert Range(-oo, 1, 1)[-1] is S.Zero
assert Range(oo, 1, -1)[-1] == 2
assert inf not in Range(oo)
assert Range(1, 10, 1)[-1] == 9
assert all(i.is_Integer for i in Range(0, -1, 1))
it = iter(Range(-oo, 0, 2))
raises(TypeError, lambda: next(it))
assert empty.intersect(S.Integers) == empty
assert Range(-1, 10, 1).intersect(S.Complexes) == Range(-1, 10, 1)
assert Range(-1, 10, 1).intersect(S.Reals) == Range(-1, 10, 1)
assert Range(-1, 10, 1).intersect(S.Rationals) == Range(-1, 10, 1)
assert Range(-1, 10, 1).intersect(S.Integers) == Range(-1, 10, 1)
assert Range(-1, 10, 1).intersect(S.Naturals) == Range(1, 10, 1)
assert Range(-1, 10, 1).intersect(S.Naturals0) == Range(0, 10, 1)
# test slicing
assert Range(1, 10, 1)[5] == 6
assert Range(1, 12, 2)[5] == 11
assert Range(1, 10, 1)[-1] == 9
assert Range(1, 10, 3)[-1] == 7
raises(ValueError, lambda: Range(oo,0,-1)[1:3:0])
raises(ValueError, lambda: Range(oo,0,-1)[:1])
raises(ValueError, lambda: Range(1, oo)[-2])
raises(ValueError, lambda: Range(-oo, 1)[2])
raises(IndexError, lambda: Range(10)[-20])
raises(IndexError, lambda: Range(10)[20])
raises(ValueError, lambda: Range(2, -oo, -2)[2:2:0])
assert Range(2, -oo, -2)[2:2:2] == empty
assert Range(2, -oo, -2)[:2:2] == Range(2, -2, -4)
raises(ValueError, lambda: Range(-oo, 4, 2)[:2:2])
assert Range(-oo, 4, 2)[::-2] == Range(2, -oo, -4)
raises(ValueError, lambda: Range(-oo, 4, 2)[::2])
assert Range(oo, 2, -2)[::] == Range(oo, 2, -2)
assert Range(-oo, 4, 2)[:-2:-2] == Range(2, 0, -4)
assert Range(-oo, 4, 2)[:-2:2] == Range(-oo, 0, 4)
raises(ValueError, lambda: Range(-oo, 4, 2)[:0:-2])
raises(ValueError, lambda: Range(-oo, 4, 2)[:2:-2])
assert Range(-oo, 4, 2)[-2::-2] == Range(0, -oo, -4)
raises(ValueError, lambda: Range(-oo, 4, 2)[-2:0:-2])
raises(ValueError, lambda: Range(-oo, 4, 2)[0::2])
assert Range(oo, 2, -2)[0::] == Range(oo, 2, -2)
raises(ValueError, lambda: Range(-oo, 4, 2)[0:-2:2])
assert Range(oo, 2, -2)[0:-2:] == Range(oo, 6, -2)
raises(ValueError, lambda: Range(oo, 2, -2)[0:2:])
raises(ValueError, lambda: Range(-oo, 4, 2)[2::-1])
assert Range(-oo, 4, 2)[-2::2] == Range(0, 4, 4)
assert Range(oo, 0, -2)[-10:0:2] == empty
raises(ValueError, lambda: Range(oo, 0, -2)[0])
raises(ValueError, lambda: Range(oo, 0, -2)[-10:10:2])
raises(ValueError, lambda: Range(oo, 0, -2)[0::-2])
assert Range(oo, 0, -2)[0:-4:-2] == empty
assert Range(oo, 0, -2)[:0:2] == empty
raises(ValueError, lambda: Range(oo, 0, -2)[:1:-1])
# test empty Range
assert Range(x, x, y) == empty
assert empty.reversed == empty
assert 0 not in empty
assert list(empty) == []
assert len(empty) == 0
assert empty.size is S.Zero
assert empty.intersect(FiniteSet(0)) is S.EmptySet
assert bool(empty) is False
raises(IndexError, lambda: empty[0])
assert empty[:0] == empty
raises(NotImplementedError, lambda: empty.inf)
raises(NotImplementedError, lambda: empty.sup)
assert empty.as_relational(x) is S.false
AB = [None] + list(range(12))
for R in [
Range(1, 10),
Range(1, 10, 2),
]:
r = list(R)
for a, b, c in itertools.product(AB, AB, [-3, -1, None, 1, 3]):
for reverse in range(2):
r = list(reversed(r))
R = R.reversed
result = list(R[a:b:c])
ans = r[a:b:c]
txt = ('\n%s[%s:%s:%s] = %s -> %s' % (
R, a, b, c, result, ans))
check = ans == result
assert check, txt
assert Range(1, 10, 1).boundary == Range(1, 10, 1)
for r in (Range(1, 10, 2), Range(1, oo, 2)):
rev = r.reversed
assert r.inf == rev.inf and r.sup == rev.sup
assert r.step == -rev.step
builtin_range = range
raises(TypeError, lambda: Range(builtin_range(1)))
assert S(builtin_range(10)) == Range(10)
assert S(builtin_range(1000000000000)) == Range(1000000000000)
# test Range.as_relational
assert Range(1, 4).as_relational(x) == (x >= 1) & (x <= 3) & Eq(Mod(x, 1), 0)
assert Range(oo, 1, -2).as_relational(x) == (x >= 3) & (x < oo) & Eq(Mod(x + 1, -2), 0)
def test_Range_symbolic():
# symbolic Range
xr = Range(x, x + 4, 5)
sr = Range(x, y, t)
i = Symbol('i', integer=True)
ip = Symbol('i', integer=True, positive=True)
ipr = Range(ip)
inr = Range(0, -ip, -1)
ir = Range(i, i + 19, 2)
ir2 = Range(i, i*8, 3*i)
i = Symbol('i', integer=True)
inf = symbols('inf', infinite=True)
raises(ValueError, lambda: Range(inf))
raises(ValueError, lambda: Range(inf, 0, -1))
raises(ValueError, lambda: Range(inf, inf, 1))
raises(ValueError, lambda: Range(1, 1, inf))
# args
assert xr.args == (x, x + 5, 5)
assert sr.args == (x, y, t)
assert ir.args == (i, i + 20, 2)
assert ir2.args == (i, 10*i, 3*i)
# reversed
raises(ValueError, lambda: xr.reversed)
raises(ValueError, lambda: sr.reversed)
assert ipr.reversed.args == (ip - 1, -1, -1)
assert inr.reversed.args == (-ip + 1, 1, 1)
assert ir.reversed.args == (i + 18, i - 2, -2)
assert ir2.reversed.args == (7*i, -2*i, -3*i)
# contains
assert inf not in sr
assert inf not in ir
assert 0 in ipr
assert 0 in inr
raises(TypeError, lambda: 1 in ipr)
raises(TypeError, lambda: -1 in inr)
assert .1 not in sr
assert .1 not in ir
assert i + 1 not in ir
assert i + 2 in ir
raises(TypeError, lambda: x in xr) # XXX is this what contains is supposed to do?
raises(TypeError, lambda: 1 in sr) # XXX is this what contains is supposed to do?
# iter
raises(ValueError, lambda: next(iter(xr)))
raises(ValueError, lambda: next(iter(sr)))
assert next(iter(ir)) == i
assert next(iter(ir2)) == i
assert sr.intersect(S.Integers) == sr
assert sr.intersect(FiniteSet(x)) == Intersection({x}, sr)
raises(ValueError, lambda: sr[:2])
raises(ValueError, lambda: xr[0])
raises(ValueError, lambda: sr[0])
# len
assert len(ir) == ir.size == 10
assert len(ir2) == ir2.size == 3
raises(ValueError, lambda: len(xr))
raises(ValueError, lambda: xr.size)
raises(ValueError, lambda: len(sr))
raises(ValueError, lambda: sr.size)
# bool
assert bool(Range(0)) == False
assert bool(xr)
assert bool(ir)
assert bool(ipr)
assert bool(inr)
raises(ValueError, lambda: bool(sr))
raises(ValueError, lambda: bool(ir2))
# inf
raises(ValueError, lambda: xr.inf)
raises(ValueError, lambda: sr.inf)
assert ipr.inf == 0
assert inr.inf == -ip + 1
assert ir.inf == i
raises(ValueError, lambda: ir2.inf)
# sup
raises(ValueError, lambda: xr.sup)
raises(ValueError, lambda: sr.sup)
assert ipr.sup == ip - 1
assert inr.sup == 0
assert ir.inf == i
raises(ValueError, lambda: ir2.sup)
# getitem
raises(ValueError, lambda: xr[0])
raises(ValueError, lambda: sr[0])
raises(ValueError, lambda: sr[-1])
raises(ValueError, lambda: sr[:2])
assert ir[:2] == Range(i, i + 4, 2)
assert ir[0] == i
assert ir[-2] == i + 16
assert ir[-1] == i + 18
assert ir2[:2] == Range(i, 7*i, 3*i)
assert ir2[0] == i
assert ir2[-2] == 4*i
assert ir2[-1] == 7*i
raises(ValueError, lambda: Range(i)[-1])
assert ipr[0] == ipr.inf == 0
assert ipr[-1] == ipr.sup == ip - 1
assert inr[0] == inr.sup == 0
assert inr[-1] == inr.inf == -ip + 1
raises(ValueError, lambda: ipr[-2])
assert ir.inf == i
assert ir.sup == i + 18
raises(ValueError, lambda: Range(i).inf)
# as_relational
assert ir.as_relational(x) == ((x >= i) & (x <= i + 18) &
Eq(Mod(-i + x, 2), 0))
assert ir2.as_relational(x) == Eq(
Mod(-i + x, 3*i), 0) & (((x >= i) & (x <= 7*i) & (3*i >= 1)) |
((x <= i) & (x >= 7*i) & (3*i <= -1)))
assert Range(i, i + 1).as_relational(x) == Eq(x, i)
assert sr.as_relational(z) == Eq(
Mod(t, 1), 0) & Eq(Mod(x, 1), 0) & Eq(Mod(-x + z, t), 0
) & (((z >= x) & (z <= -t + y) & (t >= 1)) |
((z <= x) & (z >= -t + y) & (t <= -1)))
assert xr.as_relational(z) == Eq(z, x) & Eq(Mod(x, 1), 0)
# symbols can clash if user wants (but it must be integer)
assert xr.as_relational(x) == Eq(Mod(x, 1), 0)
# contains() for symbolic values (issue #18146)
e = Symbol('e', integer=True, even=True)
o = Symbol('o', integer=True, odd=True)
assert Range(5).contains(i) == And(i >= 0, i <= 4)
assert Range(1).contains(i) == Eq(i, 0)
assert Range(-oo, 5, 1).contains(i) == (i <= 4)
assert Range(-oo, oo).contains(i) == True
assert Range(0, 8, 2).contains(i) == Contains(i, Range(0, 8, 2))
assert Range(0, 8, 2).contains(e) == And(e >= 0, e <= 6)
assert Range(0, 8, 2).contains(2*i) == And(2*i >= 0, 2*i <= 6)
assert Range(0, 8, 2).contains(o) == False
assert Range(1, 9, 2).contains(e) == False
assert Range(1, 9, 2).contains(o) == And(o >= 1, o <= 7)
assert Range(8, 0, -2).contains(o) == False
assert Range(9, 1, -2).contains(o) == And(o >= 3, o <= 9)
assert Range(-oo, 8, 2).contains(i) == Contains(i, Range(-oo, 8, 2))
def test_range_range_intersection():
for a, b, r in [
(Range(0), Range(1), S.EmptySet),
(Range(3), Range(4, oo), S.EmptySet),
(Range(3), Range(-3, -1), S.EmptySet),
(Range(1, 3), Range(0, 3), Range(1, 3)),
(Range(1, 3), Range(1, 4), Range(1, 3)),
(Range(1, oo, 2), Range(2, oo, 2), S.EmptySet),
(Range(0, oo, 2), Range(oo), Range(0, oo, 2)),
(Range(0, oo, 2), Range(100), Range(0, 100, 2)),
(Range(2, oo, 2), Range(oo), Range(2, oo, 2)),
(Range(0, oo, 2), Range(5, 6), S.EmptySet),
(Range(2, 80, 1), Range(55, 71, 4), Range(55, 71, 4)),
(Range(0, 6, 3), Range(-oo, 5, 3), S.EmptySet),
(Range(0, oo, 2), Range(5, oo, 3), Range(8, oo, 6)),
(Range(4, 6, 2), Range(2, 16, 7), S.EmptySet),]:
assert a.intersect(b) == r
assert a.intersect(b.reversed) == r
assert a.reversed.intersect(b) == r
assert a.reversed.intersect(b.reversed) == r
a, b = b, a
assert a.intersect(b) == r
assert a.intersect(b.reversed) == r
assert a.reversed.intersect(b) == r
assert a.reversed.intersect(b.reversed) == r
def test_range_interval_intersection():
p = symbols('p', positive=True)
assert isinstance(Range(3).intersect(Interval(p, p + 2)), Intersection)
assert Range(4).intersect(Interval(0, 3)) == Range(4)
assert Range(4).intersect(Interval(-oo, oo)) == Range(4)
assert Range(4).intersect(Interval(1, oo)) == Range(1, 4)
assert Range(4).intersect(Interval(1.1, oo)) == Range(2, 4)
assert Range(4).intersect(Interval(0.1, 3)) == Range(1, 4)
assert Range(4).intersect(Interval(0.1, 3.1)) == Range(1, 4)
assert Range(4).intersect(Interval.open(0, 3)) == Range(1, 3)
assert Range(4).intersect(Interval.open(0.1, 0.5)) is S.EmptySet
assert Interval(-1, 5).intersect(S.Complexes) == Interval(-1, 5)
assert Interval(-1, 5).intersect(S.Reals) == Interval(-1, 5)
assert Interval(-1, 5).intersect(S.Integers) == Range(-1, 6)
assert Interval(-1, 5).intersect(S.Naturals) == Range(1, 6)
assert Interval(-1, 5).intersect(S.Naturals0) == Range(0, 6)
# Null Range intersections
assert Range(0).intersect(Interval(0.2, 0.8)) is S.EmptySet
assert Range(0).intersect(Interval(-oo, oo)) is S.EmptySet
def test_range_is_finite_set():
assert Range(-100, 100).is_finite_set is True
assert Range(2, oo).is_finite_set is False
assert Range(-oo, 50).is_finite_set is False
assert Range(-oo, oo).is_finite_set is False
assert Range(oo, -oo).is_finite_set is True
assert Range(0, 0).is_finite_set is True
assert Range(oo, oo).is_finite_set is True
assert Range(-oo, -oo).is_finite_set is True
n = Symbol('n', integer=True)
m = Symbol('m', integer=True)
assert Range(n, n + 49).is_finite_set is True
assert Range(n, 0).is_finite_set is True
assert Range(-3, n + 7).is_finite_set is True
assert Range(n, m).is_finite_set is True
assert Range(n + m, m - n).is_finite_set is True
assert Range(n, n + m + n).is_finite_set is True
assert Range(n, oo).is_finite_set is False
assert Range(-oo, n).is_finite_set is False
assert Range(n, -oo).is_finite_set is True
assert Range(oo, n).is_finite_set is True
def test_Range_is_iterable():
assert Range(-100, 100).is_iterable is True
assert Range(2, oo).is_iterable is False
assert Range(-oo, 50).is_iterable is False
assert Range(-oo, oo).is_iterable is False
assert Range(oo, -oo).is_iterable is True
assert Range(0, 0).is_iterable is True
assert Range(oo, oo).is_iterable is True
assert Range(-oo, -oo).is_iterable is True
n = Symbol('n', integer=True)
m = Symbol('m', integer=True)
p = Symbol('p', integer=True, positive=True)
assert Range(n, n + 49).is_iterable is True
assert Range(n, 0).is_iterable is False
assert Range(-3, n + 7).is_iterable is False
assert Range(-3, p + 7).is_iterable is False # Should work with better __iter__
assert Range(n, m).is_iterable is False
assert Range(n + m, m - n).is_iterable is False
assert Range(n, n + m + n).is_iterable is False
assert Range(n, oo).is_iterable is False
assert Range(-oo, n).is_iterable is False
x = Symbol('x')
assert Range(x, x + 49).is_iterable is False
assert Range(x, 0).is_iterable is False
assert Range(-3, x + 7).is_iterable is False
assert Range(x, m).is_iterable is False
assert Range(x + m, m - x).is_iterable is False
assert Range(x, x + m + x).is_iterable is False
assert Range(x, oo).is_iterable is False
assert Range(-oo, x).is_iterable is False
def test_Integers_eval_imageset():
ans = ImageSet(Lambda(x, 2*x + Rational(3, 7)), S.Integers)
im = imageset(Lambda(x, -2*x + Rational(3, 7)), S.Integers)
assert im == ans
im = imageset(Lambda(x, -2*x - Rational(11, 7)), S.Integers)
assert im == ans
y = Symbol('y')
L = imageset(x, 2*x + y, S.Integers)
assert y + 4 in L
a, b, c = 0.092, 0.433, 0.341
assert a in imageset(x, a + c*x, S.Integers)
assert b in imageset(x, b + c*x, S.Integers)
_x = symbols('x', negative=True)
eq = _x**2 - _x + 1
assert imageset(_x, eq, S.Integers).lamda.expr == _x**2 + _x + 1
eq = 3*_x - 1
assert imageset(_x, eq, S.Integers).lamda.expr == 3*_x + 2
assert imageset(x, (x, 1/x), S.Integers) == \
ImageSet(Lambda(x, (x, 1/x)), S.Integers)
def test_Range_eval_imageset():
a, b, c = symbols('a b c')
assert imageset(x, a*(x + b) + c, Range(3)) == \
imageset(x, a*x + a*b + c, Range(3))
eq = (x + 1)**2
assert imageset(x, eq, Range(3)).lamda.expr == eq
eq = a*(x + b) + c
r = Range(3, -3, -2)
imset = imageset(x, eq, r)
assert imset.lamda.expr != eq
assert list(imset) == [eq.subs(x, i).expand() for i in list(r)]
def test_fun():
assert (FiniteSet(*ImageSet(Lambda(x, sin(pi*x/4)),
Range(-10, 11))) == FiniteSet(-1, -sqrt(2)/2, 0, sqrt(2)/2, 1))
def test_Range_is_empty():
i = Symbol('i', integer=True)
n = Symbol('n', negative=True, integer=True)
p = Symbol('p', positive=True, integer=True)
assert Range(0).is_empty
assert not Range(1).is_empty
assert Range(1, 0).is_empty
assert not Range(-1, 0).is_empty
assert Range(i).is_empty is None
assert Range(n).is_empty
assert Range(p).is_empty is False
assert Range(n, 0).is_empty is False
assert Range(n, p).is_empty is False
assert Range(p, n).is_empty
assert Range(n, -1).is_empty is None
assert Range(p, n, -1).is_empty is False
def test_Reals():
assert 5 in S.Reals
assert S.Pi in S.Reals
assert -sqrt(2) in S.Reals
assert (2, 5) not in S.Reals
assert sqrt(-1) not in S.Reals
assert S.Reals == Interval(-oo, oo)
assert S.Reals != Interval(0, oo)
assert S.Reals.is_subset(Interval(-oo, oo))
assert S.Reals.intersect(Range(-oo, oo)) == Range(-oo, oo)
assert S.ComplexInfinity not in S.Reals
assert S.NaN not in S.Reals
assert x + S.ComplexInfinity not in S.Reals
def test_Complex():
assert 5 in S.Complexes
assert 5 + 4*I in S.Complexes
assert S.Pi in S.Complexes
assert -sqrt(2) in S.Complexes
assert -I in S.Complexes
assert sqrt(-1) in S.Complexes
assert S.Complexes.intersect(S.Reals) == S.Reals
assert S.Complexes.union(S.Reals) == S.Complexes
assert S.Complexes == ComplexRegion(S.Reals*S.Reals)
assert (S.Complexes == ComplexRegion(Interval(1, 2)*Interval(3, 4))) == False
assert str(S.Complexes) == "Complexes"
assert repr(S.Complexes) == "Complexes"
def take(n, iterable):
"Return first n items of the iterable as a list"
return list(itertools.islice(iterable, n))
def test_intersections():
assert S.Integers.intersect(S.Reals) == S.Integers
assert 5 in S.Integers.intersect(S.Reals)
assert 5 in S.Integers.intersect(S.Reals)
assert -5 not in S.Naturals.intersect(S.Reals)
assert 5.5 not in S.Integers.intersect(S.Reals)
assert 5 in S.Integers.intersect(Interval(3, oo))
assert -5 in S.Integers.intersect(Interval(-oo, 3))
assert all(x.is_Integer
for x in take(10, S.Integers.intersect(Interval(3, oo)) ))
def test_infinitely_indexed_set_1():
from sympy.abc import n, m
assert imageset(Lambda(n, n), S.Integers) == imageset(Lambda(m, m), S.Integers)
assert imageset(Lambda(n, 2*n), S.Integers).intersect(
imageset(Lambda(m, 2*m + 1), S.Integers)) is S.EmptySet
assert imageset(Lambda(n, 2*n), S.Integers).intersect(
imageset(Lambda(n, 2*n + 1), S.Integers)) is S.EmptySet
assert imageset(Lambda(m, 2*m), S.Integers).intersect(
imageset(Lambda(n, 3*n), S.Integers)).dummy_eq(
ImageSet(Lambda(t, 6*t), S.Integers))
assert imageset(x, x/2 + Rational(1, 3), S.Integers).intersect(S.Integers) is S.EmptySet
assert imageset(x, x/2 + S.Half, S.Integers).intersect(S.Integers) is S.Integers
# https://github.com/sympy/sympy/issues/17355
S53 = ImageSet(Lambda(n, 5*n + 3), S.Integers)
assert S53.intersect(S.Integers) == S53
def test_infinitely_indexed_set_2():
from sympy.abc import n
a = Symbol('a', integer=True)
assert imageset(Lambda(n, n), S.Integers) == \
imageset(Lambda(n, n + a), S.Integers)
assert imageset(Lambda(n, n + pi), S.Integers) == \
imageset(Lambda(n, n + a + pi), S.Integers)
assert imageset(Lambda(n, n), S.Integers) == \
imageset(Lambda(n, -n + a), S.Integers)
assert imageset(Lambda(n, -6*n), S.Integers) == \
ImageSet(Lambda(n, 6*n), S.Integers)
assert imageset(Lambda(n, 2*n + pi), S.Integers) == \
ImageSet(Lambda(n, 2*n + pi - 2), S.Integers)
def test_imageset_intersect_real():
from sympy.abc import n
assert imageset(Lambda(n, n + (n - 1)*(n + 1)*I), S.Integers).intersect(S.Reals) == FiniteSet(-1, 1)
im = (n - 1)*(n + S.Half)
assert imageset(Lambda(n, n + im*I), S.Integers
).intersect(S.Reals) == FiniteSet(1)
assert imageset(Lambda(n, n + im*(n + 1)*I), S.Naturals0
).intersect(S.Reals) == FiniteSet(1)
assert imageset(Lambda(n, n/2 + im.expand()*I), S.Integers
).intersect(S.Reals) == ImageSet(Lambda(x, x/2), ConditionSet(
n, Eq(n**2 - n/2 - S(1)/2, 0), S.Integers))
assert imageset(Lambda(n, n/(1/n - 1) + im*(n + 1)*I), S.Integers
).intersect(S.Reals) == FiniteSet(S.Half)
assert imageset(Lambda(n, n/(n - 6) +
(n - 3)*(n + 1)*I/(2*n + 2)), S.Integers).intersect(
S.Reals) == FiniteSet(-1)
assert imageset(Lambda(n, n/(n**2 - 9) +
(n - 3)*(n + 1)*I/(2*n + 2)), S.Integers).intersect(
S.Reals) is S.EmptySet
s = ImageSet(
Lambda(n, -I*(I*(2*pi*n - pi/4) + log(Abs(sqrt(-I))))),
S.Integers)
# s is unevaluated, but after intersection the result
# should be canonical
assert s.intersect(S.Reals) == imageset(
Lambda(n, 2*n*pi - pi/4), S.Integers) == ImageSet(
Lambda(n, 2*pi*n + pi*Rational(7, 4)), S.Integers)
def test_imageset_intersect_interval():
from sympy.abc import n
f1 = ImageSet(Lambda(n, n*pi), S.Integers)
f2 = ImageSet(Lambda(n, 2*n), Interval(0, pi))
f3 = ImageSet(Lambda(n, 2*n*pi + pi/2), S.Integers)
# complex expressions
f4 = ImageSet(Lambda(n, n*I*pi), S.Integers)
f5 = ImageSet(Lambda(n, 2*I*n*pi + pi/2), S.Integers)
# non-linear expressions
f6 = ImageSet(Lambda(n, log(n)), S.Integers)
f7 = ImageSet(Lambda(n, n**2), S.Integers)
f8 = ImageSet(Lambda(n, Abs(n)), S.Integers)
f9 = ImageSet(Lambda(n, exp(n)), S.Naturals0)
assert f1.intersect(Interval(-1, 1)) == FiniteSet(0)
assert f1.intersect(Interval(0, 2*pi, False, True)) == FiniteSet(0, pi)
assert f2.intersect(Interval(1, 2)) == Interval(1, 2)
assert f3.intersect(Interval(-1, 1)) == S.EmptySet
assert f3.intersect(Interval(-5, 5)) == FiniteSet(pi*Rational(-3, 2), pi/2)
assert f4.intersect(Interval(-1, 1)) == FiniteSet(0)
assert f4.intersect(Interval(1, 2)) == S.EmptySet
assert f5.intersect(Interval(0, 1)) == S.EmptySet
assert f6.intersect(Interval(0, 1)) == FiniteSet(S.Zero, log(2))
assert f7.intersect(Interval(0, 10)) == Intersection(f7, Interval(0, 10))
assert f8.intersect(Interval(0, 2)) == Intersection(f8, Interval(0, 2))
assert f9.intersect(Interval(1, 2)) == Intersection(f9, Interval(1, 2))
def test_imageset_intersect_diophantine():
from sympy.abc import m, n
# Check that same lambda variable for both ImageSets is handled correctly
img1 = ImageSet(Lambda(n, 2*n + 1), S.Integers)
img2 = ImageSet(Lambda(n, 4*n + 1), S.Integers)
assert img1.intersect(img2) == img2
# Empty solution set returned by diophantine:
assert ImageSet(Lambda(n, 2*n), S.Integers).intersect(
ImageSet(Lambda(n, 2*n + 1), S.Integers)) == S.EmptySet
# Check intersection with S.Integers:
assert ImageSet(Lambda(n, 9/n + 20*n/3), S.Integers).intersect(
S.Integers) == FiniteSet(-61, -23, 23, 61)
# Single solution (2, 3) for diophantine solution:
assert ImageSet(Lambda(n, (n - 2)**2), S.Integers).intersect(
ImageSet(Lambda(n, -(n - 3)**2), S.Integers)) == FiniteSet(0)
# Single parametric solution for diophantine solution:
assert ImageSet(Lambda(n, n**2 + 5), S.Integers).intersect(
ImageSet(Lambda(m, 2*m), S.Integers)).dummy_eq(ImageSet(
Lambda(n, 4*n**2 + 4*n + 6), S.Integers))
# 4 non-parametric solution couples for dioph. equation:
assert ImageSet(Lambda(n, n**2 - 9), S.Integers).intersect(
ImageSet(Lambda(m, -m**2), S.Integers)) == FiniteSet(-9, 0)
# Double parametric solution for diophantine solution:
assert ImageSet(Lambda(m, m**2 + 40), S.Integers).intersect(
ImageSet(Lambda(n, 41*n), S.Integers)).dummy_eq(Intersection(
ImageSet(Lambda(m, m**2 + 40), S.Integers),
ImageSet(Lambda(n, 41*n), S.Integers)))
# Check that diophantine returns *all* (8) solutions (permute=True)
assert ImageSet(Lambda(n, n**4 - 2**4), S.Integers).intersect(
ImageSet(Lambda(m, -m**4 + 3**4), S.Integers)) == FiniteSet(0, 65)
assert ImageSet(Lambda(n, pi/12 + n*5*pi/12), S.Integers).intersect(
ImageSet(Lambda(n, 7*pi/12 + n*11*pi/12), S.Integers)).dummy_eq(ImageSet(
Lambda(n, 55*pi*n/12 + 17*pi/4), S.Integers))
# TypeError raised by diophantine (#18081)
assert ImageSet(Lambda(n, n*log(2)), S.Integers).intersection(
S.Integers).dummy_eq(Intersection(ImageSet(
Lambda(n, n*log(2)), S.Integers), S.Integers))
# NotImplementedError raised by diophantine (no solver for cubic_thue)
assert ImageSet(Lambda(n, n**3 + 1), S.Integers).intersect(
ImageSet(Lambda(n, n**3), S.Integers)).dummy_eq(Intersection(
ImageSet(Lambda(n, n**3 + 1), S.Integers),
ImageSet(Lambda(n, n**3), S.Integers)))
def test_infinitely_indexed_set_3():
from sympy.abc import n, m
assert imageset(Lambda(m, 2*pi*m), S.Integers).intersect(
imageset(Lambda(n, 3*pi*n), S.Integers)).dummy_eq(
ImageSet(Lambda(t, 6*pi*t), S.Integers))
assert imageset(Lambda(n, 2*n + 1), S.Integers) == \
imageset(Lambda(n, 2*n - 1), S.Integers)
assert imageset(Lambda(n, 3*n + 2), S.Integers) == \
imageset(Lambda(n, 3*n - 1), S.Integers)
def test_ImageSet_simplification():
from sympy.abc import n, m
assert imageset(Lambda(n, n), S.Integers) == S.Integers
assert imageset(Lambda(n, sin(n)),
imageset(Lambda(m, tan(m)), S.Integers)) == \
imageset(Lambda(m, sin(tan(m))), S.Integers)
assert imageset(n, 1 + 2*n, S.Naturals) == Range(3, oo, 2)
assert imageset(n, 1 + 2*n, S.Naturals0) == Range(1, oo, 2)
assert imageset(n, 1 - 2*n, S.Naturals) == Range(-1, -oo, -2)
def test_ImageSet_contains():
assert (2, S.Half) in imageset(x, (x, 1/x), S.Integers)
assert imageset(x, x + I*3, S.Integers).intersection(S.Reals) is S.EmptySet
i = Dummy(integer=True)
q = imageset(x, x + I*y, S.Integers).intersection(S.Reals)
assert q.subs(y, I*i).intersection(S.Integers) is S.Integers
q = imageset(x, x + I*y/x, S.Integers).intersection(S.Reals)
assert q.subs(y, 0) is S.Integers
assert q.subs(y, I*i*x).intersection(S.Integers) is S.Integers
z = cos(1)**2 + sin(1)**2 - 1
q = imageset(x, x + I*z, S.Integers).intersection(S.Reals)
assert q is not S.EmptySet
def test_ComplexRegion_contains():
r = Symbol('r', real=True)
# contains in ComplexRegion
a = Interval(2, 3)
b = Interval(4, 6)
c = Interval(7, 9)
c1 = ComplexRegion(a*b)
c2 = ComplexRegion(Union(a*b, c*a))
assert 2.5 + 4.5*I in c1
assert 2 + 4*I in c1
assert 3 + 4*I in c1
assert 8 + 2.5*I in c2
assert 2.5 + 6.1*I not in c1
assert 4.5 + 3.2*I not in c1
assert c1.contains(x) == Contains(x, c1, evaluate=False)
assert c1.contains(r) == False
assert c2.contains(x) == Contains(x, c2, evaluate=False)
assert c2.contains(r) == False
r1 = Interval(0, 1)
theta1 = Interval(0, 2*S.Pi)
c3 = ComplexRegion(r1*theta1, polar=True)
assert (0.5 + I*6/10) in c3
assert (S.Half + I*6/10) in c3
assert (S.Half + .6*I) in c3
assert (0.5 + .6*I) in c3
assert I in c3
assert 1 in c3
assert 0 in c3
assert 1 + I not in c3
assert 1 - I not in c3
assert c3.contains(x) == Contains(x, c3, evaluate=False)
assert c3.contains(r + 2*I) == Contains(
r + 2*I, c3, evaluate=False) # is in fact False
assert c3.contains(1/(1 + r**2)) == Contains(
1/(1 + r**2), c3, evaluate=False) # is in fact True
r2 = Interval(0, 3)
theta2 = Interval(pi, 2*pi, left_open=True)
c4 = ComplexRegion(r2*theta2, polar=True)
assert c4.contains(0) == True
assert c4.contains(2 + I) == False
assert c4.contains(-2 + I) == False
assert c4.contains(-2 - I) == True
assert c4.contains(2 - I) == True
assert c4.contains(-2) == False
assert c4.contains(2) == True
assert c4.contains(x) == Contains(x, c4, evaluate=False)
assert c4.contains(3/(1 + r**2)) == Contains(
3/(1 + r**2), c4, evaluate=False) # is in fact True
raises(ValueError, lambda: ComplexRegion(r1*theta1, polar=2))
def test_symbolic_Range():
n = Symbol('n')
raises(ValueError, lambda: Range(n)[0])
raises(IndexError, lambda: Range(n, n)[0])
raises(ValueError, lambda: Range(n, n+1)[0])
raises(ValueError, lambda: Range(n).size)
n = Symbol('n', integer=True)
raises(ValueError, lambda: Range(n)[0])
raises(IndexError, lambda: Range(n, n)[0])
assert Range(n, n+1)[0] == n
raises(ValueError, lambda: Range(n).size)
assert Range(n, n+1).size == 1
n = Symbol('n', integer=True, nonnegative=True)
raises(ValueError, lambda: Range(n)[0])
raises(IndexError, lambda: Range(n, n)[0])
assert Range(n+1)[0] == 0
assert Range(n, n+1)[0] == n
assert Range(n).size == n
assert Range(n+1).size == n+1
assert Range(n, n+1).size == 1
n = Symbol('n', integer=True, positive=True)
assert Range(n)[0] == 0
assert Range(n, n+1)[0] == n
assert Range(n).size == n
assert Range(n, n+1).size == 1
m = Symbol('m', integer=True, positive=True)
assert Range(n, n+m)[0] == n
assert Range(n, n+m).size == m
assert Range(n, n+1).size == 1
assert Range(n, n+m, 2).size == floor(m/2)
m = Symbol('m', integer=True, positive=True, even=True)
assert Range(n, n+m, 2).size == m/2
def test_issue_18400():
n = Symbol('n', integer=True)
raises(ValueError, lambda: imageset(lambda x: x*2, Range(n)))
n = Symbol('n', integer=True, positive=True)
# No exception
assert imageset(lambda x: x*2, Range(n)) == imageset(lambda x: x*2, Range(n))
def test_ComplexRegion_intersect():
# Polar form
X_axis = ComplexRegion(Interval(0, oo)*FiniteSet(0, S.Pi), polar=True)
unit_disk = ComplexRegion(Interval(0, 1)*Interval(0, 2*S.Pi), polar=True)
upper_half_unit_disk = ComplexRegion(Interval(0, 1)*Interval(0, S.Pi), polar=True)
upper_half_disk = ComplexRegion(Interval(0, oo)*Interval(0, S.Pi), polar=True)
lower_half_disk = ComplexRegion(Interval(0, oo)*Interval(S.Pi, 2*S.Pi), polar=True)
right_half_disk = ComplexRegion(Interval(0, oo)*Interval(-S.Pi/2, S.Pi/2), polar=True)
first_quad_disk = ComplexRegion(Interval(0, oo)*Interval(0, S.Pi/2), polar=True)
assert upper_half_disk.intersect(unit_disk) == upper_half_unit_disk
assert right_half_disk.intersect(first_quad_disk) == first_quad_disk
assert upper_half_disk.intersect(right_half_disk) == first_quad_disk
assert upper_half_disk.intersect(lower_half_disk) == X_axis
c1 = ComplexRegion(Interval(0, 4)*Interval(0, 2*S.Pi), polar=True)
assert c1.intersect(Interval(1, 5)) == Interval(1, 4)
assert c1.intersect(Interval(4, 9)) == FiniteSet(4)
assert c1.intersect(Interval(5, 12)) is S.EmptySet
# Rectangular form
X_axis = ComplexRegion(Interval(-oo, oo)*FiniteSet(0))
unit_square = ComplexRegion(Interval(-1, 1)*Interval(-1, 1))
upper_half_unit_square = ComplexRegion(Interval(-1, 1)*Interval(0, 1))
upper_half_plane = ComplexRegion(Interval(-oo, oo)*Interval(0, oo))
lower_half_plane = ComplexRegion(Interval(-oo, oo)*Interval(-oo, 0))
right_half_plane = ComplexRegion(Interval(0, oo)*Interval(-oo, oo))
first_quad_plane = ComplexRegion(Interval(0, oo)*Interval(0, oo))
assert upper_half_plane.intersect(unit_square) == upper_half_unit_square
assert right_half_plane.intersect(first_quad_plane) == first_quad_plane
assert upper_half_plane.intersect(right_half_plane) == first_quad_plane
assert upper_half_plane.intersect(lower_half_plane) == X_axis
c1 = ComplexRegion(Interval(-5, 5)*Interval(-10, 10))
assert c1.intersect(Interval(2, 7)) == Interval(2, 5)
assert c1.intersect(Interval(5, 7)) == FiniteSet(5)
assert c1.intersect(Interval(6, 9)) is S.EmptySet
# unevaluated object
C1 = ComplexRegion(Interval(0, 1)*Interval(0, 2*S.Pi), polar=True)
C2 = ComplexRegion(Interval(-1, 1)*Interval(-1, 1))
assert C1.intersect(C2) == Intersection(C1, C2, evaluate=False)
def test_ComplexRegion_union():
# Polar form
c1 = ComplexRegion(Interval(0, 1)*Interval(0, 2*S.Pi), polar=True)
c2 = ComplexRegion(Interval(0, 1)*Interval(0, S.Pi), polar=True)
c3 = ComplexRegion(Interval(0, oo)*Interval(0, S.Pi), polar=True)
c4 = ComplexRegion(Interval(0, oo)*Interval(S.Pi, 2*S.Pi), polar=True)
p1 = Union(Interval(0, 1)*Interval(0, 2*S.Pi), Interval(0, 1)*Interval(0, S.Pi))
p2 = Union(Interval(0, oo)*Interval(0, S.Pi), Interval(0, oo)*Interval(S.Pi, 2*S.Pi))
assert c1.union(c2) == ComplexRegion(p1, polar=True)
assert c3.union(c4) == ComplexRegion(p2, polar=True)
# Rectangular form
c5 = ComplexRegion(Interval(2, 5)*Interval(6, 9))
c6 = ComplexRegion(Interval(4, 6)*Interval(10, 12))
c7 = ComplexRegion(Interval(0, 10)*Interval(-10, 0))
c8 = ComplexRegion(Interval(12, 16)*Interval(14, 20))
p3 = Union(Interval(2, 5)*Interval(6, 9), Interval(4, 6)*Interval(10, 12))
p4 = Union(Interval(0, 10)*Interval(-10, 0), Interval(12, 16)*Interval(14, 20))
assert c5.union(c6) == ComplexRegion(p3)
assert c7.union(c8) == ComplexRegion(p4)
assert c1.union(Interval(2, 4)) == Union(c1, Interval(2, 4), evaluate=False)
assert c5.union(Interval(2, 4)) == Union(c5, ComplexRegion.from_real(Interval(2, 4)))
def test_ComplexRegion_from_real():
c1 = ComplexRegion(Interval(0, 1) * Interval(0, 2 * S.Pi), polar=True)
raises(ValueError, lambda: c1.from_real(c1))
assert c1.from_real(Interval(-1, 1)) == ComplexRegion(Interval(-1, 1) * FiniteSet(0), False)
def test_ComplexRegion_measure():
a, b = Interval(2, 5), Interval(4, 8)
theta1, theta2 = Interval(0, 2*S.Pi), Interval(0, S.Pi)
c1 = ComplexRegion(a*b)
c2 = ComplexRegion(Union(a*theta1, b*theta2), polar=True)
assert c1.measure == 12
assert c2.measure == 9*pi
def test_normalize_theta_set():
# Interval
assert normalize_theta_set(Interval(pi, 2*pi)) == \
Union(FiniteSet(0), Interval.Ropen(pi, 2*pi))
assert normalize_theta_set(Interval(pi*Rational(9, 2), 5*pi)) == Interval(pi/2, pi)
assert normalize_theta_set(Interval(pi*Rational(-3, 2), pi/2)) == Interval.Ropen(0, 2*pi)
assert normalize_theta_set(Interval.open(pi*Rational(-3, 2), pi/2)) == \
Union(Interval.Ropen(0, pi/2), Interval.open(pi/2, 2*pi))
assert normalize_theta_set(Interval.open(pi*Rational(-7, 2), pi*Rational(-3, 2))) == \
Union(Interval.Ropen(0, pi/2), Interval.open(pi/2, 2*pi))
assert normalize_theta_set(Interval(-pi/2, pi/2)) == \
Union(Interval(0, pi/2), Interval.Ropen(pi*Rational(3, 2), 2*pi))
assert normalize_theta_set(Interval.open(-pi/2, pi/2)) == \
Union(Interval.Ropen(0, pi/2), Interval.open(pi*Rational(3, 2), 2*pi))
assert normalize_theta_set(Interval(-4*pi, 3*pi)) == Interval.Ropen(0, 2*pi)
assert normalize_theta_set(Interval(pi*Rational(-3, 2), -pi/2)) == Interval(pi/2, pi*Rational(3, 2))
assert normalize_theta_set(Interval.open(0, 2*pi)) == Interval.open(0, 2*pi)
assert normalize_theta_set(Interval.Ropen(-pi/2, pi/2)) == \
Union(Interval.Ropen(0, pi/2), Interval.Ropen(pi*Rational(3, 2), 2*pi))
assert normalize_theta_set(Interval.Lopen(-pi/2, pi/2)) == \
Union(Interval(0, pi/2), Interval.open(pi*Rational(3, 2), 2*pi))
assert normalize_theta_set(Interval(-pi/2, pi/2)) == \
Union(Interval(0, pi/2), Interval.Ropen(pi*Rational(3, 2), 2*pi))
assert normalize_theta_set(Interval.open(4*pi, pi*Rational(9, 2))) == Interval.open(0, pi/2)
assert normalize_theta_set(Interval.Lopen(4*pi, pi*Rational(9, 2))) == Interval.Lopen(0, pi/2)
assert normalize_theta_set(Interval.Ropen(4*pi, pi*Rational(9, 2))) == Interval.Ropen(0, pi/2)
assert normalize_theta_set(Interval.open(3*pi, 5*pi)) == \
Union(Interval.Ropen(0, pi), Interval.open(pi, 2*pi))
# FiniteSet
assert normalize_theta_set(FiniteSet(0, pi, 3*pi)) == FiniteSet(0, pi)
assert normalize_theta_set(FiniteSet(0, pi/2, pi, 2*pi)) == FiniteSet(0, pi/2, pi)
assert normalize_theta_set(FiniteSet(0, -pi/2, -pi, -2*pi)) == FiniteSet(0, pi, pi*Rational(3, 2))
assert normalize_theta_set(FiniteSet(pi*Rational(-3, 2), pi/2)) == \
FiniteSet(pi/2)
assert normalize_theta_set(FiniteSet(2*pi)) == FiniteSet(0)
# Unions
assert normalize_theta_set(Union(Interval(0, pi/3), Interval(pi/2, pi))) == \
Union(Interval(0, pi/3), Interval(pi/2, pi))
assert normalize_theta_set(Union(Interval(0, pi), Interval(2*pi, pi*Rational(7, 3)))) == \
Interval(0, pi)
# ValueError for non-real sets
raises(ValueError, lambda: normalize_theta_set(S.Complexes))
# NotImplementedError for subset of reals
raises(NotImplementedError, lambda: normalize_theta_set(Interval(0, 1)))
# NotImplementedError without pi as coefficient
raises(NotImplementedError, lambda: normalize_theta_set(Interval(1, 2*pi)))
raises(NotImplementedError, lambda: normalize_theta_set(Interval(2*pi, 10)))
raises(NotImplementedError, lambda: normalize_theta_set(FiniteSet(0, 3, 3*pi)))
def test_ComplexRegion_FiniteSet():
x, y, z, a, b, c = symbols('x y z a b c')
# Issue #9669
assert ComplexRegion(FiniteSet(a, b, c)*FiniteSet(x, y, z)) == \
FiniteSet(a + I*x, a + I*y, a + I*z, b + I*x, b + I*y,
b + I*z, c + I*x, c + I*y, c + I*z)
assert ComplexRegion(FiniteSet(2)*FiniteSet(3)) == FiniteSet(2 + 3*I)
def test_union_RealSubSet():
assert (S.Complexes).union(Interval(1, 2)) == S.Complexes
assert (S.Complexes).union(S.Integers) == S.Complexes
def test_SetKind_fancySet():
G = lambda *args: ImageSet(Lambda(x, x ** 2), *args)
assert G(Interval(1, 4)).kind is SetKind(NumberKind)
assert G(FiniteSet(1, 4)).kind is SetKind(NumberKind)
assert S.Rationals.kind is SetKind(NumberKind)
assert S.Naturals.kind is SetKind(NumberKind)
assert S.Integers.kind is SetKind(NumberKind)
assert Range(3).kind is SetKind(NumberKind)
a = Interval(2, 3)
b = Interval(4, 6)
c1 = ComplexRegion(a*b)
assert c1.kind is SetKind(TupleKind(NumberKind, NumberKind))
def test_issue_9980():
c1 = ComplexRegion(Interval(1, 2)*Interval(2, 3))
c2 = ComplexRegion(Interval(1, 5)*Interval(1, 3))
R = Union(c1, c2)
assert simplify(R) == ComplexRegion(Union(Interval(1, 2)*Interval(2, 3), \
Interval(1, 5)*Interval(1, 3)), False)
assert c1.func(*c1.args) == c1
assert R.func(*R.args) == R
def test_issue_11732():
interval12 = Interval(1, 2)
finiteset1234 = FiniteSet(1, 2, 3, 4)
pointComplex = Tuple(1, 5)
assert (interval12 in S.Naturals) == False
assert (interval12 in S.Naturals0) == False
assert (interval12 in S.Integers) == False
assert (interval12 in S.Complexes) == False
assert (finiteset1234 in S.Naturals) == False
assert (finiteset1234 in S.Naturals0) == False
assert (finiteset1234 in S.Integers) == False
assert (finiteset1234 in S.Complexes) == False
assert (pointComplex in S.Naturals) == False
assert (pointComplex in S.Naturals0) == False
assert (pointComplex in S.Integers) == False
assert (pointComplex in S.Complexes) == True
def test_issue_11730():
unit = Interval(0, 1)
square = ComplexRegion(unit ** 2)
assert Union(S.Complexes, FiniteSet(oo)) != S.Complexes
assert Union(S.Complexes, FiniteSet(eye(4))) != S.Complexes
assert Union(unit, square) == square
assert Intersection(S.Reals, square) == unit
def test_issue_11938():
unit = Interval(0, 1)
ival = Interval(1, 2)
cr1 = ComplexRegion(ival * unit)
assert Intersection(cr1, S.Reals) == ival
assert Intersection(cr1, unit) == FiniteSet(1)
arg1 = Interval(0, S.Pi)
arg2 = FiniteSet(S.Pi)
arg3 = Interval(S.Pi / 4, 3 * S.Pi / 4)
cp1 = ComplexRegion(unit * arg1, polar=True)
cp2 = ComplexRegion(unit * arg2, polar=True)
cp3 = ComplexRegion(unit * arg3, polar=True)
assert Intersection(cp1, S.Reals) == Interval(-1, 1)
assert Intersection(cp2, S.Reals) == Interval(-1, 0)
assert Intersection(cp3, S.Reals) == FiniteSet(0)
def test_issue_11914():
a, b = Interval(0, 1), Interval(0, pi)
c, d = Interval(2, 3), Interval(pi, 3 * pi / 2)
cp1 = ComplexRegion(a * b, polar=True)
cp2 = ComplexRegion(c * d, polar=True)
assert -3 in cp1.union(cp2)
assert -3 in cp2.union(cp1)
assert -5 not in cp1.union(cp2)
def test_issue_9543():
assert ImageSet(Lambda(x, x**2), S.Naturals).is_subset(S.Reals)
def test_issue_16871():
assert ImageSet(Lambda(x, x), FiniteSet(1)) == {1}
assert ImageSet(Lambda(x, x - 3), S.Integers
).intersection(S.Integers) is S.Integers
@XFAIL
def test_issue_16871b():
assert ImageSet(Lambda(x, x - 3), S.Integers).is_subset(S.Integers)
def test_issue_18050():
assert imageset(Lambda(x, I*x + 1), S.Integers
) == ImageSet(Lambda(x, I*x + 1), S.Integers)
assert imageset(Lambda(x, 3*I*x + 4 + 8*I), S.Integers
) == ImageSet(Lambda(x, 3*I*x + 4 + 2*I), S.Integers)
# no 'Mod' for next 2 tests:
assert imageset(Lambda(x, 2*x + 3*I), S.Integers
) == ImageSet(Lambda(x, 2*x + 3*I), S.Integers)
r = Symbol('r', positive=True)
assert imageset(Lambda(x, r*x + 10), S.Integers
) == ImageSet(Lambda(x, r*x + 10), S.Integers)
# reduce real part:
assert imageset(Lambda(x, 3*x + 8 + 5*I), S.Integers
) == ImageSet(Lambda(x, 3*x + 2 + 5*I), S.Integers)
def test_Rationals():
assert S.Integers.is_subset(S.Rationals)
assert S.Naturals.is_subset(S.Rationals)
assert S.Naturals0.is_subset(S.Rationals)
assert S.Rationals.is_subset(S.Reals)
assert S.Rationals.inf is -oo
assert S.Rationals.sup is oo
it = iter(S.Rationals)
assert [next(it) for i in range(12)] == [
0, 1, -1, S.Half, 2, Rational(-1, 2), -2,
Rational(1, 3), 3, Rational(-1, 3), -3, Rational(2, 3)]
assert Basic() not in S.Rationals
assert S.Half in S.Rationals
assert S.Rationals.contains(0.5) == Contains(0.5, S.Rationals, evaluate=False)
assert 2 in S.Rationals
r = symbols('r', rational=True)
assert r in S.Rationals
raises(TypeError, lambda: x in S.Rationals)
# issue #18134:
assert S.Rationals.boundary == S.Reals
assert S.Rationals.closure == S.Reals
assert S.Rationals.is_open == False
assert S.Rationals.is_closed == False
def test_NZQRC_unions():
# check that all trivial number set unions are simplified:
nbrsets = (S.Naturals, S.Naturals0, S.Integers, S.Rationals,
S.Reals, S.Complexes)
unions = (Union(a, b) for a in nbrsets for b in nbrsets)
assert all(u.is_Union is False for u in unions)
def test_imageset_intersection():
n = Dummy()
s = ImageSet(Lambda(n, -I*(I*(2*pi*n - pi/4) +
log(Abs(sqrt(-I))))), S.Integers)
assert s.intersect(S.Reals) == ImageSet(
Lambda(n, 2*pi*n + pi*Rational(7, 4)), S.Integers)
def test_issue_17858():
assert 1 in Range(-oo, oo)
assert 0 in Range(oo, -oo, -1)
assert oo not in Range(-oo, oo)
assert -oo not in Range(-oo, oo)
def test_issue_17859():
r = Range(-oo,oo)
raises(ValueError,lambda: r[::2])
raises(ValueError, lambda: r[::-2])
r = Range(oo,-oo,-1)
raises(ValueError,lambda: r[::2])
raises(ValueError, lambda: r[::-2])