示例#1
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def test_dmp_from_to_dict():
    assert dmp_from_dict({}, 1, ZZ) == [[]]
    assert dmp_to_dict([[]], 1) == {}

    assert dmp_to_dict([], 0, ZZ, zero=True) == {(0,): ZZ(0)}
    assert dmp_to_dict([[]], 1, ZZ, zero=True) == {(0, 0): ZZ(0)}

    f = [[3], [], [], [2], [], [], [], [], [8]]
    g = {(8, 0): 3, (5, 0): 2, (0, 0): 8}

    assert dmp_from_dict(g, 1, ZZ) == f
    assert dmp_to_dict(f, 1) == g
示例#2
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def test_dmp_from_to_dict():
    assert dmp_from_dict({}, 0, ZZ) == []

    assert dmp_to_dict([], 0) == {}

    f = [3, 0, 0, 2, 0, 0, 0, 0, 8]
    h = {(8, ): 3, (5, ): 2, (0, ): 8}

    assert dmp_from_dict(h, 0, ZZ) == f

    assert dmp_to_dict(f, 0) == h

    R, x, y = ring("x,y", ZZ)

    f = [R(3), R(0), R(2), R(0), R(0), R(8)]
    h = {(5, ): R(3), (3, ): R(2), (0, ): R(8)}

    assert dmp_from_dict(h, 0, R) == f

    assert dmp_to_dict(f, 0) == h

    assert dmp_to_dict([1, 0, 5, 0, 7], 0) == {(0, ): 7, (2, ): 5, (4, ): 1}

    assert dmp_from_dict({}, 1, ZZ) == [[]]
    assert dmp_to_dict([[]], 1) == {}

    f = [[3], [], [], [2], [], [], [], [], [8]]
    g = {(8, 0): 3, (5, 0): 2, (0, 0): 8}

    assert dmp_from_dict(g, 1, ZZ) == f
    assert dmp_to_dict(f, 1) == g
示例#3
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def test_dup_from_to_dict():
    assert dup_from_dict({}, ZZ) == []

    assert dmp_to_dict([], 0) == {}

    assert dmp_to_dict([], 0, ZZ, zero=True) == {(0, ): ZZ(0)}

    f = [3, 0, 0, 2, 0, 0, 0, 0, 8]
    h = {(8, ): 3, (5, ): 2, (0, ): 8}

    assert dup_from_dict(h, ZZ) == f

    assert dmp_to_dict(f, 0) == h

    R, x, y = ring("x,y", ZZ)

    f = [R(3), R(0), R(2), R(0), R(0), R(8)]
    h = {(5, ): R(3), (3, ): R(2), (0, ): R(8)}

    assert dup_from_dict(h, R) == f

    assert dmp_to_dict(f, 0) == h

    assert dmp_to_dict([1, 0, 5, 0, 7], 0) == {(0, ): 7, (2, ): 5, (4, ): 1}
示例#4
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def dmp_lift(f, u, K):
    """
    Convert algebraic coefficients to integers in ``K[X]``.

    Examples
    ========

    >>> from diofant.polys import ring, QQ
    >>> from diofant import I

    >>> K = QQ.algebraic_field(I)
    >>> R, x = ring("x", K)

    >>> f = x**2 + K([QQ(1), QQ(0)])*x + K([QQ(2), QQ(0)])

    >>> R.dmp_lift(f)
    x**8 + 2*x**6 + 9*x**4 - 8*x**2 + 16
    """
    if not K.is_Algebraic:
        raise DomainError(
            'computation can be done only in an algebraic domain')

    F, monoms, polys = dmp_to_dict(f, u), [], []

    for monom, coeff in F.items():
        if not coeff.is_ground:
            monoms.append(monom)

    perms = variations([-1, 1], len(monoms), repetition=True)

    for perm in perms:
        G = dict(F)

        for sign, monom in zip(perm, monoms):
            if sign == -1:
                G[monom] = -G[monom]

        polys.append(dmp_from_dict(G, u, K))

    return dmp_convert(dmp_expand(polys, u, K), u, K, K.domain)