예제 #1
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def test_pickling_polys_errors():
    # TODO: TypeError: __init__() takes at least 3 arguments (1 given)
    # for c in (ExactQuotientFailed, ExactQuotientFailed(x, 3*x, ZZ)):
    #    check(c)

    # TODO: TypeError: can't pickle instancemethod objects
    # for c in (OperationNotSupported, OperationNotSupported(Poly(x), Poly.gcd)):
    #    check(c)

    for c in (HeuristicGCDFailed, HeuristicGCDFailed(), HomomorphismFailed,
              HomomorphismFailed(), IsomorphismFailed, IsomorphismFailed(),
              ExtraneousFactors, ExtraneousFactors(), EvaluationFailed,
              EvaluationFailed(),
              RefinementFailed, RefinementFailed(), CoercionFailed,
              CoercionFailed(), NotInvertible, NotInvertible(), NotReversible,
              NotReversible(), NotAlgebraic, NotAlgebraic(), DomainError,
              DomainError(), PolynomialError, PolynomialError(),
              UnificationFailed, UnificationFailed(), GeneratorsError,
              GeneratorsError(), GeneratorsNeeded, GeneratorsNeeded()):
        check(c)

    # TODO: PicklingError: Can't pickle <function <lambda> at 0x38578c0>: it's not found as __main__.<lambda>
    # for c in (ComputationFailed, ComputationFailed(lambda t: t, 3, None)):
    #    check(c)

    for c in (UnivariatePolynomialError, UnivariatePolynomialError(),
              MultivariatePolynomialError, MultivariatePolynomialError()):
        check(c)

    # TODO: TypeError: __init__() takes at least 3 arguments (1 given)
    # for c in (PolificationFailed, PolificationFailed({}, x, x, False)):
    #    check(c)

    for c in (OptionError, OptionError(), FlagError, FlagError()):
        check(c)
예제 #2
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def dup_half_gcdex(f, g, K):
    """
    Half extended Euclidean algorithm in `F[x]`.

    Returns ``(s, h)`` such that ``h = gcd(f, g)`` and ``s*f = h (mod g)``.

    Examples
    ========

    >>> from diofant.polys import ring, QQ
    >>> R, x = ring("x", QQ)

    >>> f = x**4 - 2*x**3 - 6*x**2 + 12*x + 15
    >>> g = x**3 + x**2 - 4*x - 4

    >>> R.dup_half_gcdex(f, g)
    (-1/5*x + 3/5, x + 1)
    """
    if not K.has_Field:
        raise DomainError("can't compute half extended GCD over %s" % K)

    a, b = [K.one], []

    while g:
        q, r = dup_div(f, g, K)
        f, g = g, r
        a, b = b, dup_sub_mul(a, q, b, K)

    a = dup_quo_ground(a, dup_LC(f, K), K)
    f = dup_monic(f, K)

    return a, f
예제 #3
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def dup_factor_list(f, K0):
    """Factor polynomials into irreducibles in `K[x]`. """
    j, f = dup_terms_gcd(f, K0)
    cont, f = dup_primitive(f, K0)

    if K0.is_FiniteField:
        coeff, factors = dup_gf_factor(f, K0)
    elif K0.is_Algebraic:
        coeff, factors = dup_ext_factor(f, K0)
    else:
        if not K0.is_Exact:
            K0_inexact, K0 = K0, K0.get_exact()
            f = dup_convert(f, K0_inexact, K0)
        else:
            K0_inexact = None

        if K0.has_Field:
            K = K0.get_ring()

            denom, f = dup_clear_denoms(f, K0, K)
            f = dup_convert(f, K0, K)
        else:
            K = K0

        if K.is_ZZ:
            coeff, factors = dup_zz_factor(f, K)
        elif K.is_Poly:
            f, u = dmp_inject(f, 0, K)

            coeff, factors = dmp_factor_list(f, u, K.domain)

            for i, (f, k) in enumerate(factors):
                factors[i] = (dmp_eject(f, u, K), k)

            coeff = K.convert(coeff, K.domain)
        else:  # pragma: no cover
            raise DomainError('factorization not supported over %s' % K0)

        if K0.has_Field:
            for i, (f, k) in enumerate(factors):
                factors[i] = (dup_convert(f, K, K0), k)

            coeff = K0.convert(coeff, K)

            if K0_inexact is None:
                coeff = coeff / denom
            else:
                for i, (f, k) in enumerate(factors):
                    f = dup_quo_ground(f, denom, K0)
                    f = dup_convert(f, K0, K0_inexact)
                    factors[i] = (f, k)

                coeff = K0_inexact.convert(coeff * denom**i, K0)
                K0 = K0_inexact

    if j:
        factors.insert(0, ([K0.one, K0.zero], j))

    return coeff * cont, _sort_factors(factors)
예제 #4
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def dmp_sqf_norm(f, u, K):
    """
    Square-free norm of ``f`` in ``K[X]``, useful over algebraic domains.

    Returns ``s``, ``f``, ``r``, such that ``g(x) = f(x-sa)`` and ``r(x) = Norm(g(x))``
    is a square-free polynomial over K, where ``a`` is the algebraic extension of ``K``.

    Examples
    ========

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

    >>> K = QQ.algebraic_field(I)
    >>> R, x, y = ring("x,y", K)
    >>> _, X, Y = ring("x,y", QQ)

    >>> s, f, r = R.dmp_sqf_norm(x*y + y**2)

    >>> s == 1
    True
    >>> f == x*y + y**2 + K([QQ(-1), QQ(0)])*y
    True
    >>> r == X**2*Y**2 + 2*X*Y**3 + Y**4 + Y**2
    True

    """
    if not u:
        return dup_sqf_norm(f, K)

    if not K.is_Algebraic:
        raise DomainError("ground domain must be algebraic")

    g = dmp_raise(K.mod.rep, u + 1, 0, K.domain)
    F = dmp_raise([K.one, -K.unit], u, 0, K)

    s = 0

    while True:
        h, _ = dmp_inject(f, u, K, front=True)
        r = dmp_resultant(g, h, u + 1, K.domain)

        if dmp_sqf_p(r, u, K.domain):
            break
        else:
            f, s = dmp_compose(f, F, u, K), s + 1

    return s, f, r
예제 #5
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    def __init__(self, dom, *ext):
        if not dom.is_QQ:
            raise DomainError("ground domain must be a rational field")

        from diofant.polys.numberfields import to_number_field

        self.orig_ext = ext
        self.ext = to_number_field(ext)
        self.mod = self.ext.minpoly.rep
        self.domain = dom

        self.ngens = 1
        self.symbols = self.gens = (self.ext, )
        self.unit = self([dom(1), dom(0)])

        self.zero = self.dtype.zero(self.mod.rep, dom)
        self.one = self.dtype.one(self.mod.rep, dom)
예제 #6
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def dup_real_imag(f, K):
    """
    Return bivariate polynomials ``f1`` and ``f2``, such that ``f = f1 + f2*I``.

    Examples
    ========

    >>> from diofant.polys import ring, ZZ
    >>> R, x,y = ring("x,y", ZZ)

    >>> R.dup_real_imag(x**3 + x**2 + x + 1)
    (x**3 + x**2 - 3*x*y**2 + x - y**2 + 1, 3*x**2*y + 2*x*y - y**3 + y)
    """
    if not K.is_ZZ and not K.is_QQ:
        raise DomainError(
            "computing real and imaginary parts is not supported over %s" % K)

    f1 = dmp_zero(1)
    f2 = dmp_zero(1)

    if not f:
        return f1, f2

    g = [[[K.one, K.zero]], [[K.one], []]]
    h = dmp_ground(f[0], 2)

    for c in f[1:]:
        h = dmp_mul(h, g, 2, K)
        h = dmp_add_term(h, dmp_ground(c, 1), 0, 2, K)

    H = dup_to_raw_dict(h)

    for k, h in H.items():
        m = k % 4

        if not m:
            f1 = dmp_add(f1, h, 1, K)
        elif m == 1:
            f2 = dmp_add(f2, h, 1, K)
        elif m == 2:
            f1 = dmp_sub(f1, h, 1, K)
        else:
            f2 = dmp_sub(f2, h, 1, K)

    return f1, f2
예제 #7
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def dup_sqf_norm(f, K):
    """
    Square-free norm of ``f`` in ``K[x]``, useful over algebraic domains.

    Returns ``s``, ``f``, ``r``, such that ``g(x) = f(x-sa)`` and ``r(x) = Norm(g(x))``
    is a square-free polynomial over K, where ``a`` is the algebraic extension of ``K``.

    Examples
    ========

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

    >>> K = QQ.algebraic_field(sqrt(3))
    >>> R, x = ring("x", K)
    >>> _, X = ring("x", QQ)

    >>> s, f, r = R.dup_sqf_norm(x**2 - 2)

    >>> s == 1
    True
    >>> f == x**2 + K([QQ(-2), QQ(0)])*x + 1
    True
    >>> r == X**4 - 10*X**2 + 1
    True

    """
    if not K.is_Algebraic:
        raise DomainError("ground domain must be algebraic")

    s, g = 0, dmp_raise(K.mod.rep, 1, 0, K.domain)

    while True:
        h, _ = dmp_inject(f, 0, K, front=True)
        r = dmp_resultant(g, h, 1, K.domain)

        if dup_sqf_p(r, K.domain):
            break
        else:
            f, s = dup_shift(f, -K.unit, K), s + 1

    return s, f, r
예제 #8
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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)
예제 #9
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 def get_ring(self):
     """Returns a ring associated with ``self``. """
     raise DomainError('there is no ring associated with %s' % self)
예제 #10
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 def algebraic_field(self, *extension):
     """Returns an algebraic field, i.e. `K(\\alpha, \ldots)`. """
     raise DomainError("can't create algebraic field over %s" % self)
예제 #11
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 def get_field(self):
     """Returns a field associated with ``self``. """
     raise DomainError('there is no field associated with %s' % self)
예제 #12
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 def get_exact(self):
     """Returns an exact domain associated with ``self``. """
     raise DomainError("there is no exact domain associated with %s" % self)
예제 #13
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def dmp_factor_list(f, u, K0):
    """Factor polynomials into irreducibles in `K[X]`. """
    if not u:
        return dup_factor_list(f, K0)

    J, f = dmp_terms_gcd(f, u, K0)
    cont, f = dmp_ground_primitive(f, u, K0)

    if K0.is_FiniteField:  # pragma: no cover
        coeff, factors = dmp_gf_factor(f, u, K0)
    elif K0.is_Algebraic:
        coeff, factors = dmp_ext_factor(f, u, K0)
    else:
        if not K0.is_Exact:
            K0_inexact, K0 = K0, K0.get_exact()
            f = dmp_convert(f, u, K0_inexact, K0)
        else:
            K0_inexact = None

        if K0.has_Field:
            K = K0.get_ring()

            denom, f = dmp_clear_denoms(f, u, K0, K)
            f = dmp_convert(f, u, K0, K)
        else:
            K = K0

        if K.is_ZZ:
            levels, f, v = dmp_exclude(f, u, K)
            coeff, factors = dmp_zz_factor(f, v, K)

            for i, (f, k) in enumerate(factors):
                factors[i] = (dmp_include(f, levels, v, K), k)
        elif K.is_Poly:
            f, v = dmp_inject(f, u, K)

            coeff, factors = dmp_factor_list(f, v, K.domain)

            for i, (f, k) in enumerate(factors):
                factors[i] = (dmp_eject(f, v, K), k)

            coeff = K.convert(coeff, K.domain)
        else:  # pragma: no cover
            raise DomainError('factorization not supported over %s' % K0)

        if K0.has_Field:
            for i, (f, k) in enumerate(factors):
                factors[i] = (dmp_convert(f, u, K, K0), k)

            coeff = K0.convert(coeff, K)

            if K0_inexact is None:
                coeff = coeff / denom
            else:
                for i, (f, k) in enumerate(factors):
                    f = dmp_quo_ground(f, denom, u, K0)
                    f = dmp_convert(f, u, K0, K0_inexact)
                    factors[i] = (f, k)

                coeff = K0_inexact.convert(coeff * denom**i, K0)
                K0 = K0_inexact

    for i, j in enumerate(reversed(J)):
        if not j:
            continue

        term = {(0, ) * (u - i) + (1, ) + (0, ) * i: K0.one}
        factors.insert(0, (dmp_from_dict(term, u, K0), j))

    return coeff * cont, _sort_factors(factors)