Beispiel #1
0
def test_field_isomorphism_pslq():
    a = AlgebraicNumber(I)
    b = AlgebraicNumber(I * sqrt(3))

    pytest.raises(NotImplementedError, lambda: field_isomorphism_pslq(a, b))

    a = AlgebraicNumber(sqrt(2))
    b = AlgebraicNumber(sqrt(3))
    c = AlgebraicNumber(sqrt(7))
    d = AlgebraicNumber(sqrt(2) + sqrt(3))
    e = AlgebraicNumber(sqrt(2) + sqrt(3) + sqrt(7))

    assert field_isomorphism_pslq(a, a) == [1, 0]
    assert field_isomorphism_pslq(a, b) is None
    assert field_isomorphism_pslq(a, c) is None
    assert field_isomorphism_pslq(a, d) == [Q(1, 2), 0, -Q(9, 2), 0]
    assert field_isomorphism_pslq(
        a, e) == [Q(1, 80), 0, -Q(1, 2), 0,
                  Q(59, 20), 0]

    assert field_isomorphism_pslq(b, a) is None
    assert field_isomorphism_pslq(b, b) == [1, 0]
    assert field_isomorphism_pslq(b, c) is None
    assert field_isomorphism_pslq(b, d) == [-Q(1, 2), 0, Q(11, 2), 0]
    assert field_isomorphism_pslq(b, e) == [
        -Q(3, 640), 0,
        Q(67, 320), 0, -Q(297, 160), 0,
        Q(313, 80), 0
    ]

    assert field_isomorphism_pslq(c, a) is None
    assert field_isomorphism_pslq(c, b) is None
    assert field_isomorphism_pslq(c, c) == [1, 0]
    assert field_isomorphism_pslq(c, d) is None
    assert field_isomorphism_pslq(c, e) == [
        Q(3, 640), 0, -Q(71, 320), 0,
        Q(377, 160), 0, -Q(469, 80), 0
    ]

    assert field_isomorphism_pslq(d, a) is None
    assert field_isomorphism_pslq(d, b) is None
    assert field_isomorphism_pslq(d, c) is None
    assert field_isomorphism_pslq(d, d) == [1, 0]
    assert field_isomorphism_pslq(d, e) == [
        -Q(3, 640), 0,
        Q(71, 320), 0, -Q(377, 160), 0,
        Q(549, 80), 0
    ]

    assert field_isomorphism_pslq(e, a) is None
    assert field_isomorphism_pslq(e, b) is None
    assert field_isomorphism_pslq(e, c) is None
    assert field_isomorphism_pslq(e, d) is None
    assert field_isomorphism_pslq(e, e) == [1, 0]

    f = AlgebraicNumber(3 * sqrt(2) + 8 * sqrt(7) - 5)

    assert field_isomorphism_pslq(
        f, e) == [Q(3, 80), 0, -Q(139, 80), 0,
                  Q(347, 20), 0, -Q(761, 20), -5]
Beispiel #2
0
def test_to_number_field():
    assert to_number_field(sqrt(2)) == AlgebraicNumber(sqrt(2))
    assert to_number_field([sqrt(2),
                            sqrt(3)]) == AlgebraicNumber(sqrt(2) + sqrt(3))

    a = AlgebraicNumber(
        sqrt(2) + sqrt(3),
        [Rational(1, 2),
         Integer(0), -Rational(9, 2),
         Integer(0)])

    assert to_number_field(sqrt(2), sqrt(2) + sqrt(3)) == a
    assert to_number_field(sqrt(2), AlgebraicNumber(sqrt(2) + sqrt(3))) == a

    pytest.raises(IsomorphismFailed, lambda: to_number_field(sqrt(2), sqrt(3)))
Beispiel #3
0
def test_to_algebraic_integer():
    a = AlgebraicNumber(sqrt(3), gen=x).to_algebraic_integer()

    assert a.minpoly == x**2 - 3
    assert a.root == sqrt(3)
    assert a.rep == DMP([QQ(1), QQ(0)], QQ)

    a = AlgebraicNumber(2 * sqrt(3), gen=x).to_algebraic_integer()
    assert a.minpoly == x**2 - 12
    assert a.root == 2 * sqrt(3)
    assert a.rep == DMP([QQ(1), QQ(0)], QQ)

    a = AlgebraicNumber(sqrt(3) / 2, gen=x).to_algebraic_integer()

    assert a.minpoly == x**2 - 12
    assert a.root == 2 * sqrt(3)
    assert a.rep == DMP([QQ(1), QQ(0)], QQ)

    a = AlgebraicNumber(sqrt(3) / 2, [Rational(7, 19), 3],
                        gen=x).to_algebraic_integer()

    assert a.minpoly == x**2 - 12
    assert a.root == 2 * sqrt(3)
    assert a.rep == DMP([QQ(7, 19), QQ(3)], QQ)
Beispiel #4
0
def test_to_number_field():
    assert to_number_field(sqrt(2)) == AlgebraicNumber(sqrt(2))
    assert to_number_field([sqrt(2),
                            sqrt(3)]) == AlgebraicNumber(sqrt(2) + sqrt(3))

    a = AlgebraicNumber(
        sqrt(2) + sqrt(3),
        [Rational(1, 2),
         Integer(0), -Rational(9, 2),
         Integer(0)])

    assert to_number_field(sqrt(2), sqrt(2) + sqrt(3)) == a
    assert to_number_field(sqrt(2), AlgebraicNumber(sqrt(2) + sqrt(3))) == a

    pytest.raises(IsomorphismFailed, lambda: to_number_field(sqrt(2), sqrt(3)))

    # issue sympy/sympy#5649
    assert AlgebraicNumber(1).rep == to_number_field(1, AlgebraicNumber(1)).rep
    assert AlgebraicNumber(sqrt(2)).rep == to_number_field(
        sqrt(2), AlgebraicNumber(sqrt(2))).rep
Beispiel #5
0
def test_AlgebraicNumber():
    minpoly, root = x**2 - 2, sqrt(2)

    a = AlgebraicNumber(root, gen=x)

    assert a.rep == DMP([QQ(1), QQ(0)], QQ)
    assert a.root == root
    assert a.alias is None
    assert a.minpoly == minpoly
    assert a.is_number

    assert a.is_aliased is False

    assert a.coeffs() == [Integer(1), Integer(0)]
    assert a.native_coeffs() == [QQ(1), QQ(0)]

    a = AlgebraicNumber(root, gen=x, alias='y')

    assert a.rep == DMP([QQ(1), QQ(0)], QQ)
    assert a.root == root
    assert a.alias == Symbol('y')
    assert a.minpoly == minpoly
    assert a.is_number

    assert a.is_aliased is True

    a = AlgebraicNumber(root, gen=x, alias=Symbol('y'))

    assert a.rep == DMP([QQ(1), QQ(0)], QQ)
    assert a.root == root
    assert a.alias == Symbol('y')
    assert a.minpoly == minpoly
    assert a.is_number

    assert a.is_aliased is True

    assert AlgebraicNumber(sqrt(2), []).rep == DMP([], QQ)

    assert AlgebraicNumber(sqrt(2), [8]).rep == DMP([QQ(8)], QQ)
    assert AlgebraicNumber(sqrt(2), [Rational(8, 3)]).rep == DMP([QQ(8, 3)],
                                                                 QQ)

    assert AlgebraicNumber(sqrt(2), [7, 3]).rep == DMP([QQ(7), QQ(3)], QQ)
    assert AlgebraicNumber(sqrt(2),
                           [Rational(7, 9), Rational(3, 2)]).rep == DMP(
                               [QQ(7, 9), QQ(3, 2)], QQ)

    assert AlgebraicNumber(sqrt(2), [1, 2, 3]).rep == DMP([QQ(2), QQ(5)], QQ)

    a = AlgebraicNumber(AlgebraicNumber(root, gen=x), [1, 2])

    assert a.rep == DMP([QQ(1), QQ(2)], QQ)
    assert a.root == root
    assert a.alias is None
    assert a.minpoly == minpoly
    assert a.is_number

    assert a.is_aliased is False

    assert a.coeffs() == [Integer(1), Integer(2)]
    assert a.native_coeffs() == [QQ(1), QQ(2)]

    a = AlgebraicNumber((minpoly, root), [1, 2])

    assert a.rep == DMP([QQ(1), QQ(2)], QQ)
    assert a.root == root
    assert a.alias is None
    assert a.minpoly == minpoly
    assert a.is_number

    assert a.is_aliased is False

    a = AlgebraicNumber((Poly(minpoly), root), [1, 2])

    assert a.rep == DMP([QQ(1), QQ(2)], QQ)
    assert a.root == root
    assert a.alias is None
    assert a.minpoly == minpoly
    assert a.is_number

    assert a.is_aliased is False

    assert AlgebraicNumber(sqrt(3)).rep == DMP([QQ(1), QQ(0)], QQ)
    assert AlgebraicNumber(-sqrt(3)).rep == DMP([-QQ(1), QQ(0)], QQ)

    a = AlgebraicNumber(sqrt(2))
    b = AlgebraicNumber(sqrt(2))

    assert a == b

    c = AlgebraicNumber(sqrt(2), gen=x)
    d = AlgebraicNumber(sqrt(2), gen=x)

    assert a == b
    assert a == c

    a = AlgebraicNumber(sqrt(2), [1, 2])
    b = AlgebraicNumber(sqrt(2), [1, 3])

    assert a != b and a != sqrt(2) + 3

    assert (a == x) is False and (a != x) is True

    a = AlgebraicNumber(sqrt(2), [1, 0])
    b = AlgebraicNumber(sqrt(2), [1, 0], alias=y)

    assert a.as_poly(x) == Poly(x)
    assert b.as_poly() == Poly(y)

    assert a.as_expr() == sqrt(2)
    assert a.as_expr(x) == x
    assert b.as_expr() == sqrt(2)
    assert b.as_expr(x) == x

    a = AlgebraicNumber(sqrt(2), [2, 3])
    b = AlgebraicNumber(sqrt(2), [2, 3], alias=y)

    p = a.as_poly()

    assert p == Poly(2 * p.gen + 3)

    assert a.as_poly(x) == Poly(2 * x + 3)
    assert b.as_poly() == Poly(2 * y + 3)

    assert a.as_expr() == 2 * sqrt(2) + 3
    assert a.as_expr(x) == 2 * x + 3
    assert b.as_expr() == 2 * sqrt(2) + 3
    assert b.as_expr(x) == 2 * x + 3

    a = AlgebraicNumber(sqrt(2))
    b = to_number_field(sqrt(2))
    assert a.args == b.args == (sqrt(2), Tuple())
    b = AlgebraicNumber(sqrt(2), alias='alpha')
    assert b.args == (sqrt(2), Tuple(), Symbol('alpha'))

    a = AlgebraicNumber(sqrt(2), [1, 2, 3])
    assert a.args == (sqrt(2), Tuple(1, 2, 3))
Beispiel #6
0
def test_field_isomorphism():
    assert field_isomorphism(3, sqrt(2)) == [3]

    assert field_isomorphism(I * sqrt(3), I * sqrt(3) / 2) == [2, 0]
    assert field_isomorphism(-I * sqrt(3), I * sqrt(3) / 2) == [-2, 0]

    assert field_isomorphism(I * sqrt(3), -I * sqrt(3) / 2) == [-2, 0]
    assert field_isomorphism(-I * sqrt(3), -I * sqrt(3) / 2) == [2, 0]

    assert field_isomorphism(2 * I * sqrt(3) / 7,
                             5 * I * sqrt(3) / 3) == [Rational(6, 35), 0]
    assert field_isomorphism(-2 * I * sqrt(3) / 7,
                             5 * I * sqrt(3) / 3) == [-Rational(6, 35), 0]

    assert field_isomorphism(2 * I * sqrt(3) / 7,
                             -5 * I * sqrt(3) / 3) == [-Rational(6, 35), 0]
    assert field_isomorphism(-2 * I * sqrt(3) / 7,
                             -5 * I * sqrt(3) / 3) == [Rational(6, 35), 0]

    assert field_isomorphism(2 * I * sqrt(3) / 7 + 27,
                             5 * I * sqrt(3) / 3) == [Rational(6, 35), 27]
    assert field_isomorphism(-2 * I * sqrt(3) / 7 + 27,
                             5 * I * sqrt(3) / 3) == [-Rational(6, 35), 27]

    assert field_isomorphism(2 * I * sqrt(3) / 7 + 27,
                             -5 * I * sqrt(3) / 3) == [-Rational(6, 35), 27]
    assert field_isomorphism(-2 * I * sqrt(3) / 7 + 27,
                             -5 * I * sqrt(3) / 3) == [Rational(6, 35), 27]

    p = AlgebraicNumber(sqrt(2) + sqrt(3))
    q = AlgebraicNumber(-sqrt(2) + sqrt(3))
    r = AlgebraicNumber(sqrt(2) - sqrt(3))
    s = AlgebraicNumber(-sqrt(2) - sqrt(3))

    pos_coeffs = [Rational(1, 2), Integer(0), -Rational(9, 2), Integer(0)]
    neg_coeffs = [-Rational(1, 2), Integer(0), Rational(9, 2), Integer(0)]

    a = AlgebraicNumber(sqrt(2))

    assert is_isomorphism_possible(a, p) is True
    assert is_isomorphism_possible(a, q) is True
    assert is_isomorphism_possible(a, r) is True
    assert is_isomorphism_possible(a, s) is True

    assert field_isomorphism(a, p, fast=True) == pos_coeffs
    assert field_isomorphism(a, q, fast=True) == neg_coeffs
    assert field_isomorphism(a, r, fast=True) == pos_coeffs
    assert field_isomorphism(a, s, fast=True) == neg_coeffs

    assert field_isomorphism(a, p, fast=False) == pos_coeffs
    assert field_isomorphism(a, q, fast=False) == neg_coeffs
    assert field_isomorphism(a, r, fast=False) == pos_coeffs
    assert field_isomorphism(a, s, fast=False) == neg_coeffs

    a = AlgebraicNumber(-sqrt(2))

    assert is_isomorphism_possible(a, p) is True
    assert is_isomorphism_possible(a, q) is True
    assert is_isomorphism_possible(a, r) is True
    assert is_isomorphism_possible(a, s) is True

    assert field_isomorphism(a, p, fast=True) == neg_coeffs
    assert field_isomorphism(a, q, fast=True) == pos_coeffs
    assert field_isomorphism(a, r, fast=True) == neg_coeffs
    assert field_isomorphism(a, s, fast=True) == pos_coeffs

    assert field_isomorphism(a, p, fast=False) == neg_coeffs
    assert field_isomorphism(a, q, fast=False) == pos_coeffs
    assert field_isomorphism(a, r, fast=False) == neg_coeffs
    assert field_isomorphism(a, s, fast=False) == pos_coeffs

    pos_coeffs = [Rational(1, 2), Integer(0), -Rational(11, 2), Integer(0)]
    neg_coeffs = [-Rational(1, 2), Integer(0), Rational(11, 2), Integer(0)]

    a = AlgebraicNumber(sqrt(3))

    assert is_isomorphism_possible(a, p) is True
    assert is_isomorphism_possible(a, q) is True
    assert is_isomorphism_possible(a, r) is True
    assert is_isomorphism_possible(a, s) is True

    assert field_isomorphism(a, p, fast=True) == neg_coeffs
    assert field_isomorphism(a, q, fast=True) == neg_coeffs
    assert field_isomorphism(a, r, fast=True) == pos_coeffs
    assert field_isomorphism(a, s, fast=True) == pos_coeffs

    assert field_isomorphism(a, p, fast=False) == neg_coeffs
    assert field_isomorphism(a, q, fast=False) == neg_coeffs
    assert field_isomorphism(a, r, fast=False) == pos_coeffs
    assert field_isomorphism(a, s, fast=False) == pos_coeffs

    a = AlgebraicNumber(-sqrt(3))

    assert is_isomorphism_possible(a, p) is True
    assert is_isomorphism_possible(a, q) is True
    assert is_isomorphism_possible(a, r) is True
    assert is_isomorphism_possible(a, s) is True

    assert field_isomorphism(a, p, fast=True) == pos_coeffs
    assert field_isomorphism(a, q, fast=True) == pos_coeffs
    assert field_isomorphism(a, r, fast=True) == neg_coeffs
    assert field_isomorphism(a, s, fast=True) == neg_coeffs

    assert field_isomorphism(a, p, fast=False) == pos_coeffs
    assert field_isomorphism(a, q, fast=False) == pos_coeffs
    assert field_isomorphism(a, r, fast=False) == neg_coeffs
    assert field_isomorphism(a, s, fast=False) == neg_coeffs

    pos_coeffs = [Rational(3, 2), Integer(0), -Rational(33, 2), -Integer(8)]
    neg_coeffs = [-Rational(3, 2), Integer(0), Rational(33, 2), -Integer(8)]

    a = AlgebraicNumber(3 * sqrt(3) - 8)

    assert is_isomorphism_possible(a, p) is True
    assert is_isomorphism_possible(a, q) is True
    assert is_isomorphism_possible(a, r) is True
    assert is_isomorphism_possible(a, s) is True

    assert field_isomorphism(a, p, fast=True) == neg_coeffs
    assert field_isomorphism(a, q, fast=True) == neg_coeffs
    assert field_isomorphism(a, r, fast=True) == pos_coeffs
    assert field_isomorphism(a, s, fast=True) == pos_coeffs

    assert field_isomorphism(a, p, fast=False) == neg_coeffs
    assert field_isomorphism(a, q, fast=False) == neg_coeffs
    assert field_isomorphism(a, r, fast=False) == pos_coeffs
    assert field_isomorphism(a, s, fast=False) == pos_coeffs

    a = AlgebraicNumber(3 * sqrt(2) + 2 * sqrt(3) + 1)

    pos_1_coeffs = [Rational(1, 2), Integer(0), -Rational(5, 2), Integer(1)]
    neg_5_coeffs = [-Rational(5, 2), Integer(0), Rational(49, 2), Integer(1)]
    pos_5_coeffs = [Rational(5, 2), Integer(0), -Rational(49, 2), Integer(1)]
    neg_1_coeffs = [-Rational(1, 2), Integer(0), Rational(5, 2), Integer(1)]

    assert is_isomorphism_possible(a, p) is True
    assert is_isomorphism_possible(a, q) is True
    assert is_isomorphism_possible(a, r) is True
    assert is_isomorphism_possible(a, s) is True

    assert field_isomorphism(a, p, fast=True) == pos_1_coeffs
    assert field_isomorphism(a, q, fast=True) == neg_5_coeffs
    assert field_isomorphism(a, r, fast=True) == pos_5_coeffs
    assert field_isomorphism(a, s, fast=True) == neg_1_coeffs

    assert field_isomorphism(a, p, fast=False) == pos_1_coeffs
    assert field_isomorphism(a, q, fast=False) == neg_5_coeffs
    assert field_isomorphism(a, r, fast=False) == pos_5_coeffs
    assert field_isomorphism(a, s, fast=False) == neg_1_coeffs

    a = AlgebraicNumber(sqrt(2))
    b = AlgebraicNumber(sqrt(3))
    c = AlgebraicNumber(sqrt(7))

    assert is_isomorphism_possible(a, b) is True
    assert is_isomorphism_possible(b, a) is True

    assert is_isomorphism_possible(c, p) is False

    assert field_isomorphism(sqrt(2), sqrt(3), fast=True) is None
    assert field_isomorphism(sqrt(3), sqrt(2), fast=True) is None

    assert field_isomorphism(sqrt(2), sqrt(3), fast=False) is None
    assert field_isomorphism(sqrt(3), sqrt(2), fast=False) is None
Beispiel #7
0
def test_minimal_polynomial():
    assert minimal_polynomial(-7, x) == x + 7
    assert minimal_polynomial(-1, x) == x + 1
    assert minimal_polynomial(0, x) == x
    assert minimal_polynomial(1, x) == x - 1
    assert minimal_polynomial(7, x) == x - 7

    assert minimal_polynomial(sqrt(2), x) == x**2 - 2
    assert minimal_polynomial(sqrt(5), x) == x**2 - 5
    assert minimal_polynomial(sqrt(6), x) == x**2 - 6

    assert minimal_polynomial(2 * sqrt(2), x) == x**2 - 8
    assert minimal_polynomial(3 * sqrt(5), x) == x**2 - 45
    assert minimal_polynomial(4 * sqrt(6), x) == x**2 - 96

    assert minimal_polynomial(2 * sqrt(2) + 3, x) == x**2 - 6 * x + 1
    assert minimal_polynomial(3 * sqrt(5) + 6, x) == x**2 - 12 * x - 9
    assert minimal_polynomial(4 * sqrt(6) + 7, x) == x**2 - 14 * x - 47

    assert minimal_polynomial(2 * sqrt(2) - 3, x) == x**2 + 6 * x + 1
    assert minimal_polynomial(3 * sqrt(5) - 6, x) == x**2 + 12 * x - 9
    assert minimal_polynomial(4 * sqrt(6) - 7, x) == x**2 + 14 * x - 47

    assert minimal_polynomial(sqrt(1 + sqrt(6)), x) == x**4 - 2 * x**2 - 5
    assert minimal_polynomial(sqrt(I + sqrt(6)), x) == x**8 - 10 * x**4 + 49

    assert minimal_polynomial(2 * I + sqrt(2 + I),
                              x) == x**4 + 4 * x**2 + 8 * x + 37

    assert minimal_polynomial(sqrt(2) + sqrt(3), x) == x**4 - 10 * x**2 + 1
    assert minimal_polynomial(sqrt(2) + sqrt(3) + sqrt(6),
                              x) == x**4 - 22 * x**2 - 48 * x - 23

    a = 1 - 9 * sqrt(2) + 7 * sqrt(3)

    assert minimal_polynomial(
        1 / a, x) == 392 * x**4 - 1232 * x**3 + 612 * x**2 + 4 * x - 1
    assert minimal_polynomial(
        1 / sqrt(a), x) == 392 * x**8 - 1232 * x**6 + 612 * x**4 + 4 * x**2 - 1

    pytest.raises(NotAlgebraic, lambda: minimal_polynomial(oo, x))
    pytest.raises(NotAlgebraic, lambda: minimal_polynomial(2**y, x))
    pytest.raises(NotAlgebraic, lambda: minimal_polynomial(sin(1), x))

    assert minimal_polynomial(sqrt(2)).dummy_eq(x**2 - 2)
    assert minimal_polynomial(sqrt(2), x) == x**2 - 2

    assert minimal_polynomial(sqrt(2), polys=True) == Poly(x**2 - 2)
    assert minimal_polynomial(sqrt(2), x, polys=True) == Poly(x**2 - 2)
    assert minimal_polynomial(sqrt(2), x, polys=True,
                              compose=False) == Poly(x**2 - 2)

    a = AlgebraicNumber(sqrt(2))
    b = AlgebraicNumber(sqrt(3))

    assert minimal_polynomial(a, x) == x**2 - 2
    assert minimal_polynomial(b, x) == x**2 - 3

    assert minimal_polynomial(a, x, polys=True) == Poly(x**2 - 2)
    assert minimal_polynomial(b, x, polys=True) == Poly(x**2 - 3)

    assert minimal_polynomial(sqrt(a / 2 + 17),
                              x) == 2 * x**4 - 68 * x**2 + 577
    assert minimal_polynomial(sqrt(b / 2 + 17),
                              x) == 4 * x**4 - 136 * x**2 + 1153

    a, b = sqrt(2) / 3 + 7, AlgebraicNumber(sqrt(2) / 3 + 7)

    f = 81*x**8 - 2268*x**6 - 4536*x**5 + 22644*x**4 + 63216*x**3 - \
        31608*x**2 - 189648*x + 141358

    assert minimal_polynomial(sqrt(a) + sqrt(sqrt(a)), x) == f
    assert minimal_polynomial(sqrt(b) + sqrt(sqrt(b)), x) == f

    assert minimal_polynomial(a**Q(3, 2),
                              x) == 729 * x**4 - 506898 * x**2 + 84604519

    # issue 5994
    eq = (-1 / (800 * sqrt(
        Rational(-1, 240) + 1 /
        (18000 *
         (Rational(-1, 17280000) + sqrt(15) * I / 28800000)**Rational(1, 3)) +
        2 *
        (Rational(-1, 17280000) + sqrt(15) * I / 28800000)**Rational(1, 3))))
    assert minimal_polynomial(eq, x) == 8000 * x**2 - 1

    ex = 1 + sqrt(2) + sqrt(3)
    mp = minimal_polynomial(ex, x)
    assert mp == x**4 - 4 * x**3 - 4 * x**2 + 16 * x - 8

    ex = 1 / (1 + sqrt(2) + sqrt(3))
    mp = minimal_polynomial(ex, x)
    assert mp == 8 * x**4 - 16 * x**3 + 4 * x**2 + 4 * x - 1

    p = (expand((1 + sqrt(2) - 2 * sqrt(3) + sqrt(7))**3))**Rational(1, 3)
    mp = minimal_polynomial(p, x)
    assert mp == x**8 - 8 * x**7 - 56 * x**6 + 448 * x**5 + 480 * x**4 - 5056 * x**3 + 1984 * x**2 + 7424 * x - 3008
    p = expand((1 + sqrt(2) - 2 * sqrt(3) + sqrt(7))**3)
    mp = minimal_polynomial(p, x)
    assert mp == x**8 - 512 * x**7 - 118208 * x**6 + 31131136 * x**5 + 647362560 * x**4 - 56026611712 * x**3 + 116994310144 * x**2 + 404854931456 * x - 27216576512

    assert minimal_polynomial(
        -sqrt(5) / 2 - S.Half + (-sqrt(5) / 2 - S.Half)**2, x) == x - 1
    a = 1 + sqrt(2)
    assert minimal_polynomial((a * sqrt(2) + a)**3, x) == x**2 - 198 * x + 1

    p = 1 / (1 + sqrt(2) + sqrt(3))
    assert minimal_polynomial(
        p, x, compose=False) == 8 * x**4 - 16 * x**3 + 4 * x**2 + 4 * x - 1

    p = 2 / (1 + sqrt(2) + sqrt(3))
    assert minimal_polynomial(
        p, x, compose=False) == x**4 - 4 * x**3 + 2 * x**2 + 4 * x - 2

    assert minimal_polynomial(1 + sqrt(2) * I, x,
                              compose=False) == x**2 - 2 * x + 3
    assert minimal_polynomial(1 / (1 + sqrt(2)) + 1, x,
                              compose=False) == x**2 - 2
    assert minimal_polynomial(sqrt(2) * I + I * (1 + sqrt(2)),
                              x,
                              compose=False) == x**4 + 18 * x**2 + 49
Beispiel #8
0
def test_pickling_polys_numberfields():
    for c in (AlgebraicNumber, AlgebraicNumber(sqrt(3))):
        check(c)
Beispiel #9
0
 def to_diofant(self, a):
     """Convert ``a`` to a Diofant object. """
     from diofant.polys.numberfields import AlgebraicNumber
     return AlgebraicNumber(self.ext, a).as_expr()
Beispiel #10
0
def test_AlgebraicNumber():
    minpoly, root = x**2 - 2, sqrt(2)

    a = AlgebraicNumber(root, gen=x)

    assert a.rep == DMP([QQ(1), QQ(0)], QQ)
    assert a.root == root
    assert a.alias is None
    assert a.minpoly == minpoly
    assert a.is_number

    assert a.is_aliased is False

    assert a.coeffs() == [Integer(1), Integer(0)]
    assert a.native_coeffs() == [QQ(1), QQ(0)]

    a = AlgebraicNumber(root, gen=x, alias='y')

    assert a.rep == DMP([QQ(1), QQ(0)], QQ)
    assert a.root == root
    assert a.alias == Symbol('y')
    assert a.minpoly == minpoly
    assert a.is_number

    assert a.is_aliased is True

    a = AlgebraicNumber(root, gen=x, alias=Symbol('y'))

    assert a.rep == DMP([QQ(1), QQ(0)], QQ)
    assert a.root == root
    assert a.alias == Symbol('y')
    assert a.minpoly == minpoly
    assert a.is_number

    assert a.is_aliased is True

    assert AlgebraicNumber(sqrt(2), []).rep == DMP([], QQ)

    assert AlgebraicNumber(sqrt(2), [8]).rep == DMP([QQ(8)], QQ)
    assert AlgebraicNumber(sqrt(2), [Rational(8, 3)]).rep == DMP([QQ(8, 3)],
                                                                 QQ)

    assert AlgebraicNumber(sqrt(2), [7, 3]).rep == DMP([QQ(7), QQ(3)], QQ)
    assert AlgebraicNumber(sqrt(2),
                           [Rational(7, 9), Rational(3, 2)]).rep == DMP(
                               [QQ(7, 9), QQ(3, 2)], QQ)

    assert AlgebraicNumber(sqrt(2), [1, 2, 3]).rep == DMP([QQ(2), QQ(5)], QQ)

    a = AlgebraicNumber(AlgebraicNumber(root, gen=x), [1, 2])

    assert a.rep == DMP([QQ(1), QQ(2)], QQ)
    assert a.root == root
    assert a.alias is None
    assert a.minpoly == minpoly
    assert a.is_number

    assert a.is_aliased is False

    assert a.coeffs() == [Integer(1), Integer(2)]
    assert a.native_coeffs() == [QQ(1), QQ(2)]

    a = AlgebraicNumber((minpoly, root), [1, 2])

    assert a.rep == DMP([QQ(1), QQ(2)], QQ)
    assert a.root == root
    assert a.alias is None
    assert a.minpoly == minpoly
    assert a.is_number

    assert a.is_aliased is False

    a = AlgebraicNumber((Poly(minpoly), root), [1, 2])

    assert a.rep == DMP([QQ(1), QQ(2)], QQ)
    assert a.root == root
    assert a.alias is None
    assert a.minpoly == minpoly
    assert a.is_number

    assert a.is_aliased is False

    assert AlgebraicNumber(sqrt(3)).rep == DMP([QQ(1), QQ(0)], QQ)
    assert AlgebraicNumber(-sqrt(3)).rep == DMP([QQ(1), QQ(0)], QQ)

    a = AlgebraicNumber(sqrt(2))
    b = AlgebraicNumber(sqrt(2))

    assert a == b

    c = AlgebraicNumber(sqrt(2), gen=x)
    d = AlgebraicNumber(sqrt(2), gen=x)

    assert a == b
    assert a == c

    a = AlgebraicNumber(sqrt(2), [1, 2])
    b = AlgebraicNumber(sqrt(2), [1, 3])

    assert a != b and a != sqrt(2) + 3

    assert (a == x) is False and (a != x) is True

    a = AlgebraicNumber(sqrt(2), [1, 0])
    b = AlgebraicNumber(sqrt(2), [1, 0], alias=y)

    assert a.as_poly(x) == Poly(x)
    assert b.as_poly() == Poly(y)

    assert a.as_expr() == sqrt(2)
    assert a.as_expr(x) == x
    assert b.as_expr() == sqrt(2)
    assert b.as_expr(x) == x

    a = AlgebraicNumber(sqrt(2), [2, 3])
    b = AlgebraicNumber(sqrt(2), [2, 3], alias=y)

    p = a.as_poly()

    assert p == Poly(2 * p.gen + 3)

    assert a.as_poly(x) == Poly(2 * x + 3)
    assert b.as_poly() == Poly(2 * y + 3)

    assert a.as_expr() == 2 * sqrt(2) + 3
    assert a.as_expr(x) == 2 * x + 3
    assert b.as_expr() == 2 * sqrt(2) + 3
    assert b.as_expr(x) == 2 * x + 3

    a = AlgebraicNumber(sqrt(2))
    b = to_number_field(sqrt(2))
    assert a.args == b.args == (sqrt(2), Tuple(1, 0))
    b = AlgebraicNumber(sqrt(2), alias='alpha')
    assert b.args == (sqrt(2), Tuple(1, 0), Symbol('alpha'))

    a = AlgebraicNumber(sqrt(2), [1, 2, 3])
    assert a.args == (sqrt(2), Tuple(2, 5))

    pytest.raises(ValueError,
                  lambda: AlgebraicNumber(RootOf(x**3 + y * x + 1, x, 0)))

    a = AlgebraicNumber(RootOf(x**3 + 2 * x - 1, x, 1), alias='alpha')
    assert a.free_symbols == set()

    # integer powers:
    assert a**0 == 1
    assert a**2 == AlgebraicNumber(a, (1, 0, 0), alias='alpha')
    assert a**5 == AlgebraicNumber(a, (1, 0, 0, 0, 0, 0), alias='alpha')
    assert a**110 == AlgebraicNumber(a, ([1] + [0] * 110), alias='alpha')
    assert (a**pi).is_Pow

    b = AlgebraicNumber(sqrt(2), (1, 0), alias='theta')
    c = b + 1
    assert c**2 == 2 * b + 3
    assert c**5 == 29 * b + 41
    assert c**-2 == 3 - 2 * b
    assert c**-11 == 5741 * b - 8119

    # arithmetics
    assert a**3 == -2 * a + 1 == a * (-2) + 1 == 1 + (-2) * a == 1 - 2 * a
    assert a**5 == a**2 + 4 * a - 2
    assert a**4 == -2 * a**2 + a == a - 2 * a**2
    assert a**110 == (-2489094528619081871 * a**2 + 3737645722703173544 * a -
                      1182958048412500088)

    assert a + a == 2 * a
    assert 2 * a - a == a
    assert Integer(1) - a == (-a) + 1

    assert (a + pi).is_Add
    assert (pi + a).is_Add
    assert (a - pi).is_Add
    assert (pi - a).is_Add
    assert (a * pi).is_Mul
    assert (pi * a).is_Mul
Beispiel #11
0
def test_minimal_polynomial():
    assert minimal_polynomial(-7, x) == x + 7
    assert minimal_polynomial(-1, x) == x + 1
    assert minimal_polynomial(0, x) == x
    assert minimal_polynomial(1, x) == x - 1
    assert minimal_polynomial(7, x) == x - 7

    assert minimal_polynomial(Rational(1, 3), x, compose=False) == 3 * x - 1

    pytest.raises(NotAlgebraic,
                  lambda: minimal_polynomial(pi, x, compose=False))
    pytest.raises(NotAlgebraic,
                  lambda: minimal_polynomial(sin(sqrt(2)), x, compose=False))
    pytest.raises(NotAlgebraic,
                  lambda: minimal_polynomial(2**pi, x, compose=False))

    assert minimal_polynomial(sqrt(2), x) == x**2 - 2
    assert minimal_polynomial(sqrt(5), x) == x**2 - 5
    assert minimal_polynomial(sqrt(6), x) == x**2 - 6

    assert minimal_polynomial(2 * sqrt(2), x) == x**2 - 8
    assert minimal_polynomial(3 * sqrt(5), x) == x**2 - 45
    assert minimal_polynomial(4 * sqrt(6), x) == x**2 - 96

    assert minimal_polynomial(2 * sqrt(2) + 3, x) == x**2 - 6 * x + 1
    assert minimal_polynomial(3 * sqrt(5) + 6, x) == x**2 - 12 * x - 9
    assert minimal_polynomial(4 * sqrt(6) + 7, x) == x**2 - 14 * x - 47

    assert minimal_polynomial(2 * sqrt(2) - 3, x) == x**2 + 6 * x + 1
    assert minimal_polynomial(3 * sqrt(5) - 6, x) == x**2 + 12 * x - 9
    assert minimal_polynomial(4 * sqrt(6) - 7, x) == x**2 + 14 * x - 47

    assert minimal_polynomial(sqrt(1 + sqrt(6)), x) == x**4 - 2 * x**2 - 5
    assert minimal_polynomial(sqrt(I + sqrt(6)), x) == x**8 - 10 * x**4 + 49

    assert minimal_polynomial(2 * I + sqrt(2 + I),
                              x) == x**4 + 4 * x**2 + 8 * x + 37

    assert minimal_polynomial(sqrt(2) + sqrt(3), x) == x**4 - 10 * x**2 + 1
    assert minimal_polynomial(sqrt(2) + sqrt(3) + sqrt(6),
                              x) == x**4 - 22 * x**2 - 48 * x - 23

    e = 1 / sqrt(sqrt(1 + sqrt(3)) - 4)
    assert minimal_polynomial(e, x) == minimal_polynomial(e, x, compose=False)
    assert minimal_polynomial(e, x) == (222 * x**8 + 240 * x**6 + 94 * x**4 +
                                        16 * x**2 + 1)

    a = 1 - 9 * sqrt(2) + 7 * sqrt(3)

    assert minimal_polynomial(
        1 / a, x) == 392 * x**4 - 1232 * x**3 + 612 * x**2 + 4 * x - 1
    assert minimal_polynomial(
        1 / sqrt(a), x) == 392 * x**8 - 1232 * x**6 + 612 * x**4 + 4 * x**2 - 1

    pytest.raises(NotAlgebraic, lambda: minimal_polynomial(oo, x))
    pytest.raises(NotAlgebraic, lambda: minimal_polynomial(2**y, x))
    pytest.raises(NotAlgebraic, lambda: minimal_polynomial(sin(1), x))

    assert minimal_polynomial(sqrt(2)).dummy_eq(x**2 - 2)
    assert minimal_polynomial(sqrt(2), x) == x**2 - 2

    assert minimal_polynomial(sqrt(2), polys=True) == Poly(x**2 - 2)
    assert minimal_polynomial(sqrt(2), x, polys=True) == Poly(x**2 - 2)
    assert minimal_polynomial(sqrt(2), x, polys=True,
                              compose=False) == Poly(x**2 - 2)

    a = AlgebraicNumber(sqrt(2))
    b = AlgebraicNumber(sqrt(3))

    assert minimal_polynomial(a, x) == x**2 - 2
    assert minimal_polynomial(b, x) == x**2 - 3

    assert minimal_polynomial(a, x, polys=True) == Poly(x**2 - 2)
    assert minimal_polynomial(b, x, polys=True) == Poly(x**2 - 3)

    assert minimal_polynomial(sqrt(a), x, polys=True) == Poly(x**4 - 2)
    assert minimal_polynomial(a + 1, x, polys=True) == Poly(x**2 - 2 * x - 1)
    assert minimal_polynomial(sqrt(a / 2 + 17),
                              x) == 2 * x**4 - 68 * x**2 + 577
    assert minimal_polynomial(sqrt(b / 2 + 17),
                              x) == 4 * x**4 - 136 * x**2 + 1153

    # issue diofant/diofant#431
    theta = AlgebraicNumber(sqrt(2), (S.Half, 17))
    assert minimal_polynomial(theta, x) == 2 * x**2 - 68 * x + 577

    theta = AlgebraicNumber(RootOf(x**7 + x - 1, x, 3), (1, 2, 0, 0, 1))
    ans = minimal_polynomial(theta, x)
    assert ans == (x**7 - 7 * x**6 + 19 * x**5 - 27 * x**4 + 63 * x**3 -
                   115 * x**2 + 82 * x - 147)
    assert minimal_polynomial(theta.as_expr(), x, compose=False) == ans
    theta = AlgebraicNumber(RootOf(x**5 + 5 * x - 1, x, 2), (1, -1, 1))
    ans = (x**30 - 15 * x**28 - 10 * x**27 + 135 * x**26 + 330 * x**25 -
           705 * x**24 - 150 * x**23 + 3165 * x**22 - 6850 * x**21 +
           7182 * x**20 + 3900 * x**19 + 4435 * x**18 + 11970 * x**17 -
           259725 * x**16 - 18002 * x**15 + 808215 * x**14 - 200310 * x**13 -
           647115 * x**12 + 299280 * x**11 - 1999332 * x**10 + 910120 * x**9 +
           2273040 * x**8 - 5560320 * x**7 + 5302000 * x**6 - 2405376 * x**5 +
           1016640 * x**4 - 804480 * x**3 + 257280 * x**2 - 53760 * x + 1280)
    assert minimal_polynomial(sqrt(theta) + root(theta, 3), x) == ans
    theta = sqrt(
        1 + 1 /
        (AlgebraicNumber(RootOf(x**3 + 4 * x - 15, x, 1), (1, 0, 1)) + 1 /
         (sqrt(3) + AlgebraicNumber(RootOf(x**3 - x + 1, x, 0), (1, 2, -1)))))
    ans = (2262264837876687263 * x**36 - 38939909597855051866 * x**34 +
           315720420314462950715 * x**32 - 1601958657418182606114 * x**30 +
           5699493671077371036494 * x**28 - 15096777696140985506150 * x**26 +
           30847690820556462893974 * x**24 - 49706549068200640994022 * x**22 +
           64013601241426223813103 * x**20 - 66358713088213594372990 * x**18 +
           55482571280904904971976 * x**16 - 37309340229165533529076 * x**14 +
           20016999328983554519040 * x**12 - 8446273798231518826782 * x**10 +
           2738866994867366499481 * x**8 - 657825125060873756424 * x**6 +
           110036313740049140508 * x**4 - 11416087328869938298 * x**2 +
           551322649782053543)
    assert minimal_polynomial(theta, x) == ans

    a, b = sqrt(2) / 3 + 7, AlgebraicNumber(sqrt(2) / 3 + 7)

    f = 81*x**8 - 2268*x**6 - 4536*x**5 + 22644*x**4 + 63216*x**3 - \
        31608*x**2 - 189648*x + 141358

    assert minimal_polynomial(sqrt(a) + sqrt(sqrt(a)), x) == f
    assert minimal_polynomial(sqrt(b) + sqrt(sqrt(b)), x) == f

    assert minimal_polynomial(a**Q(3, 2),
                              x) == 729 * x**4 - 506898 * x**2 + 84604519

    a = AlgebraicNumber(RootOf(x**3 + x - 1, x, 0))
    assert minimal_polynomial(1 / a**2, x) == x**3 - x**2 - 2 * x - 1

    # issue sympy/sympy#5994
    eq = (-1 / (800 * sqrt(
        Rational(-1, 240) + 1 /
        (18000 *
         (Rational(-1, 17280000) + sqrt(15) * I / 28800000)**Rational(1, 3)) +
        2 *
        (Rational(-1, 17280000) + sqrt(15) * I / 28800000)**Rational(1, 3))))
    assert minimal_polynomial(eq, x) == 8000 * x**2 - 1

    ex = 1 + sqrt(2) + sqrt(3)
    mp = minimal_polynomial(ex, x)
    assert mp == x**4 - 4 * x**3 - 4 * x**2 + 16 * x - 8

    ex = 1 / (1 + sqrt(2) + sqrt(3))
    mp = minimal_polynomial(ex, x)
    assert mp == 8 * x**4 - 16 * x**3 + 4 * x**2 + 4 * x - 1

    p = (expand((1 + sqrt(2) - 2 * sqrt(3) + sqrt(7))**3))**Rational(1, 3)
    mp = minimal_polynomial(p, x)
    assert mp == x**8 - 8 * x**7 - 56 * x**6 + 448 * x**5 + 480 * x**4 - 5056 * x**3 + 1984 * x**2 + 7424 * x - 3008
    p = expand((1 + sqrt(2) - 2 * sqrt(3) + sqrt(7))**3)
    mp = minimal_polynomial(p, x)
    assert mp == x**8 - 512 * x**7 - 118208 * x**6 + 31131136 * x**5 + 647362560 * x**4 - 56026611712 * x**3 + 116994310144 * x**2 + 404854931456 * x - 27216576512

    assert minimal_polynomial(
        -sqrt(5) / 2 - S.Half + (-sqrt(5) / 2 - S.Half)**2, x) == x - 1
    a = 1 + sqrt(2)
    assert minimal_polynomial((a * sqrt(2) + a)**3, x) == x**2 - 198 * x + 1

    p = 1 / (1 + sqrt(2) + sqrt(3))
    assert minimal_polynomial(
        p, x, compose=False) == 8 * x**4 - 16 * x**3 + 4 * x**2 + 4 * x - 1

    p = 2 / (1 + sqrt(2) + sqrt(3))
    assert minimal_polynomial(
        p, x, compose=False) == x**4 - 4 * x**3 + 2 * x**2 + 4 * x - 2

    assert minimal_polynomial(1 + sqrt(2) * I, x,
                              compose=False) == x**2 - 2 * x + 3
    assert minimal_polynomial(1 / (1 + sqrt(2)) + 1, x,
                              compose=False) == x**2 - 2
    assert minimal_polynomial(sqrt(2) * I + I * (1 + sqrt(2)),
                              x,
                              compose=False) == x**4 + 18 * x**2 + 49