Python densearith.dmp_mul_ground函数代码示例

def dmp_cancel(f, g, u, K, multout=True):
    """
    Cancel common factors in a rational function ``f/g``.

    **Examples**

    >>> from sympy.polys.domains import ZZ
    >>> from sympy.polys.euclidtools import dmp_cancel

    >>> f = ZZ.map([[2], [0], [-2]])
    >>> g = ZZ.map([[1], [-2], [1]])

    >>> dmp_cancel(f, g, 1, ZZ)
    ([[2], [2]], [[1], [-1]])

    """
    if dmp_zero_p(f, u) or dmp_zero_p(g, u):
        if multout:
            return f, g
        else:
            return K.one, K.one, f, g

    K0 = None

    if K.has_Field and K.has_assoc_Ring:
        K0, K = K, K.get_ring()

        cq, f = dmp_clear_denoms(f, u, K0, K, convert=True)
        cp, g = dmp_clear_denoms(g, u, K0, K, convert=True)
    else:
        cp, cq = K.one, K.one

    _, p, q = dmp_inner_gcd(f, g, u, K)

    if K0 is not None:
        p = dmp_convert(p, u, K, K0)
        q = dmp_convert(q, u, K, K0)

        K = K0

    p_neg = K.is_negative(dmp_ground_LC(p, u, K))
    q_neg = K.is_negative(dmp_ground_LC(q, u, K))

    if p_neg and q_neg:
        p, q = dmp_neg(p, u, K), dmp_neg(q, u, K)
    elif p_neg:
        cp, p = -cp, dmp_neg(p, u, K)
    elif q_neg:
        cp, q = -cp, dmp_neg(q, u, K)

    if not multout:
        return cp, cq, p, q

    p = dmp_mul_ground(p, cp, u, K)
    q = dmp_mul_ground(q, cq, u, K)

    return p, q

def test_dmp_mul_ground():
    assert dmp_mul_ground(f_0, ZZ(2), 2, ZZ) == [
        [[ZZ(2),ZZ(4),ZZ(6)], [ZZ(4)]],
        [[ZZ(6)]],
        [[ZZ(8),ZZ(10),ZZ(12)], [ZZ(2),ZZ(4),ZZ(2)], [ZZ(2)]]
    ]

    assert dmp_mul_ground(F_0, QQ(1,2), 2, QQ) == [
        [[QQ(1,14),QQ(2,14),QQ(3,14)], [QQ(2,14)]],
        [[QQ(3,14)]],
        [[QQ(4,14),QQ(5,14),QQ(6,14)], [QQ(1,14),QQ(2,14),QQ(1,14)], [QQ(1,14)]]
    ]

def dmp_zz_wang_lead_coeffs(f, T, cs, E, H, A, u, K):
    """Wang/EEZ: Compute correct leading coefficients. """
    C, J, v = [], [0]*len(E), u-1

    for h in H:
        c = dmp_one(v, K)
        d = dup_LC(h, K)*cs

        for i in reversed(xrange(len(E))):
            k, e, (t, _) = 0, E[i], T[i]

            while not (d % e):
                d, k = d//e, k+1

            if k != 0:
                c, J[i] = dmp_mul(c, dmp_pow(t, k, v, K), v, K), 1

        C.append(c)

    if any([ not j for j in J ]):
        raise ExtraneousFactors # pragma: no cover

    CC, HH = [], []

    for c, h in zip(C, H):
        d = dmp_eval_tail(c, A, v, K)
        lc = dup_LC(h, K)

        if K.is_one(cs):
            cc = lc//d
        else:
            g = K.gcd(lc, d)
            d, cc = d//g, lc//g
            h, cs = dup_mul_ground(h, d, K), cs//d

        c = dmp_mul_ground(c, cc, v, K)

        CC.append(c)
        HH.append(h)

    if K.is_one(cs):
        return f, HH, CC

    CCC, HHH = [], []

    for c, h in zip(CC, HH):
        CCC.append(dmp_mul_ground(c, cs, v, K))
        HHH.append(dmp_mul_ground(h, cs, 0, K))

    f = dmp_mul_ground(f, cs**(len(H)-1), u, K)

    return f, HHH, CCC

def dmp_cancel(f, g, u, K, include=True):
    """
    Cancel common factors in a rational function `f/g`.

    Examples
    ========

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

    >>> R.dmp_cancel(2*x**2 - 2, x**2 - 2*x + 1)
    (2*x + 2, x - 1)

    """
    K0 = None

    if K.has_Field and K.has_assoc_Ring:
        K0, K = K, K.get_ring()

        cq, f = dmp_clear_denoms(f, u, K0, K, convert=True)
        cp, g = dmp_clear_denoms(g, u, K0, K, convert=True)
    else:
        cp, cq = K.one, K.one

    _, p, q = dmp_inner_gcd(f, g, u, K)

    if K0 is not None:
        _, cp, cq = K.cofactors(cp, cq)

        p = dmp_convert(p, u, K, K0)
        q = dmp_convert(q, u, K, K0)

        K = K0

    p_neg = K.is_negative(dmp_ground_LC(p, u, K))
    q_neg = K.is_negative(dmp_ground_LC(q, u, K))

    if p_neg and q_neg:
        p, q = dmp_neg(p, u, K), dmp_neg(q, u, K)
    elif p_neg:
        cp, p = -cp, dmp_neg(p, u, K)
    elif q_neg:
        cp, q = -cp, dmp_neg(q, u, K)

    if not include:
        return cp, cq, p, q

    p = dmp_mul_ground(p, cp, u, K)
    q = dmp_mul_ground(q, cq, u, K)

    return p, q

def dmp_rr_lcm(f, g, u, K):
    """
    Computes polynomial LCM over a ring in `K[X]`.

    Examples
    ========

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

    >>> f = x**2 + 2*x*y + y**2
    >>> g = x**2 + x*y

    >>> R.dmp_rr_lcm(f, g)
    x**3 + 2*x**2*y + x*y**2

    """
    fc, f = dmp_ground_primitive(f, u, K)
    gc, g = dmp_ground_primitive(g, u, K)

    c = K.lcm(fc, gc)

    h = dmp_quo(dmp_mul(f, g, u, K),
                dmp_gcd(f, g, u, K), u, K)

    return dmp_mul_ground(h, c, u, K)

def dmp_sqf_list_include(f, u, K, all=False):
    """
    Return square-free decomposition of a polynomial in ``K[x]``.

    Examples
    ========

    >>> from sympy.polys.domains import ZZ
    >>> from sympy.polys.sqfreetools import dmp_sqf_list_include

    >>> f = ZZ.map([[1], [2, 0], [1, 0, 0], [], [], []])

    >>> dmp_sqf_list_include(f, 1, ZZ)
    [([[1]], 1), ([[1], [1, 0]], 2), ([[1], []], 3)]

    >>> dmp_sqf_list_include(f, 1, ZZ, all=True)
    [([[1]], 1), ([[1], [1, 0]], 2), ([[1], []], 3)]

    """
    if not u:
        return dup_sqf_list_include(f, K, all=all)

    coeff, factors = dmp_sqf_list(f, u, K, all=all)

    if factors and factors[0][1] == 1:
        g = dmp_mul_ground(factors[0][0], coeff, u, K)
        return [(g, 1)] + factors[1:]
    else:
        g = dmp_ground(coeff, u)
        return [(g, 1)] + factors

def dmp_discriminant(f, u, K):
    """
    Computes discriminant of a polynomial in `K[X]`.

    Examples
    ========

    >>> from sympy.polys import ring, ZZ
    >>> R, x,y,z,t = ring("x,y,z,t", ZZ)

    >>> R.dmp_discriminant(x**2*y + x*z + t)
    -4*y*t + z**2

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

    d, v = dmp_degree(f, u), u - 1

    if d <= 0:
        return dmp_zero(v)
    else:
        s = (-1)**((d*(d - 1)) // 2)
        c = dmp_LC(f, K)

        r = dmp_resultant(f, dmp_diff(f, 1, u, K), u, K)
        c = dmp_mul_ground(c, K(s), v, K)

        return dmp_quo(r, c, v, K)

def dmp_rr_lcm(f, g, u, K):
    """
    Computes polynomial LCM over a ring in ``K[X]``.

    **Examples**

    >>> from sympy.polys.domains import ZZ
    >>> from sympy.polys.euclidtools import dmp_rr_lcm

    >>> f = ZZ.map([[1], [2, 0], [1, 0, 0]])
    >>> g = ZZ.map([[1], [1, 0], []])

    >>> dmp_rr_lcm(f, g, 1, ZZ)
    [[1], [2, 0], [1, 0, 0], []]

    """
    fc, f = dmp_ground_primitive(f, u, K)
    gc, g = dmp_ground_primitive(g, u, K)

    c = K.lcm(fc, gc)

    h = dmp_exquo(dmp_mul(f, g, u, K),
                  dmp_gcd(f, g, u, K), u, K)

    return dmp_mul_ground(h, c, u, K)

def dmp_discriminant(f, u, K):
    """
    Computes discriminant of a polynomial in ``K[X]``.

    **Examples**

    >>> from sympy.polys.domains import ZZ
    >>> from sympy.polys.euclidtools import dmp_discriminant

    >>> f = ZZ.map([[[[1]], [[]]], [[[1], []]], [[[1, 0]]]])

    >>> dmp_discriminant(f, 3, ZZ)
    [[[-4, 0]], [[1], [], []]]

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

    d, v = dmp_degree(f, u), u-1

    if d <= 0:
        return dmp_zero(v)
    else:
        s = (-1)**((d*(d-1)) // 2)
        c = dmp_LC(f, K)

        r = dmp_resultant(f, dmp_diff(f, 1, u, K), u, K)
        c = dmp_mul_ground(c, K(s), v, K)

        return dmp_exquo(r, c, v, K)

def dmp_eval(f, a, u, K):
    """
    Evaluate a polynomial at ``x_0 = a`` in ``K[X]`` using the Horner scheme.

    Examples
    ========

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

    >>> R.dmp_eval(2*x*y + 3*x + y + 2, 2)
    5*y + 8

    """
    if not u:
        return dup_eval(f, a, K)

    if not a:
        return dmp_TC(f, K)

    result, v = dmp_LC(f, K), u - 1

    for coeff in f[1:]:
        result = dmp_mul_ground(result, a, v, K)
        result = dmp_add(result, coeff, v, K)

    return result

def dmp_eval(f, a, u, K):
    """
    Evaluate a polynomial at ``x_0 = a`` in ``K[X]`` using the Horner scheme.

    Examples
    ========

    >>> from sympy.polys.domains import ZZ
    >>> from sympy.polys.densetools import dmp_eval

    >>> f = ZZ.map([[2, 3], [1, 2]])

    >>> dmp_eval(f, 2, 1, ZZ)
    [5, 8]

    """
    if not u:
        return dup_eval(f, a, K)

    if not a:
        return dmp_TC(f, K)

    result, v = dmp_LC(f, K), u - 1

    for coeff in f[1:]:
        result = dmp_mul_ground(result, a, v, K)
        result = dmp_add(result, coeff, v, K)

    return result

def dmp_clear_denoms(f, u, K0, K1=None, convert=False):
    """
    Clear denominators, i.e. transform ``K_0`` to ``K_1``.

    Examples
    ========

    >>> from sympy.polys.domains import QQ, ZZ
    >>> from sympy.polys.densetools import dmp_clear_denoms

    >>> f = [[QQ(1,2)], [QQ(1,3), QQ(1)]]
    >>> dmp_clear_denoms(f, 1, QQ, convert=False)
    (6, [[3/1], [2/1, 6/1]])

    >>> f = [[QQ(1,2)], [QQ(1,3), QQ(1)]]
    >>> dmp_clear_denoms(f, 1, QQ, convert=True)
    (6, [[3], [2, 6]])

    """
    if not u:
        return dup_clear_denoms(f, K0, K1, convert=convert)

    if K1 is None:
        K1 = K0.get_ring()

    common = _rec_clear_denoms(f, u, K0, K1)

    if not K1.is_one(common):
        f = dmp_mul_ground(f, common, u, K0)

    if not convert:
        return common, f
    else:
        return common, dmp_convert(f, u, K0, K1)

def dmp_sqf_list_include(f, u, K, all=False):
    """
    Return square-free decomposition of a polynomial in ``K[x]``.

    Examples
    ========

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

    >>> f = x**5 + 2*x**4*y + x**3*y**2

    >>> R.dmp_sqf_list_include(f)
    [(1, 1), (x + y, 2), (x, 3)]
    >>> R.dmp_sqf_list_include(f, all=True)
    [(1, 1), (x + y, 2), (x, 3)]

    """
    if not u:
        return dup_sqf_list_include(f, K, all=all)

    coeff, factors = dmp_sqf_list(f, u, K, all=all)

    if factors and factors[0][1] == 1:
        g = dmp_mul_ground(factors[0][0], coeff, u, K)
        return [(g, 1)] + factors[1:]
    else:
        g = dmp_ground(coeff, u)
        return [(g, 1)] + factors

def dmp_qq_heu_gcd(f, g, u, K0):
    """
    Heuristic polynomial GCD in `Q[X]`.

    Returns ``(h, cff, cfg)`` such that ``a = gcd(f, g)``,
    ``cff = quo(f, h)``, and ``cfg = quo(g, h)``.

    Examples
    ========

    >>> from sympy.polys.domains import QQ
    >>> from sympy.polys.euclidtools import dmp_qq_heu_gcd

    >>> f = [[QQ(1,4)], [QQ(1), QQ(0)], [QQ(1), QQ(0), QQ(0)]]
    >>> g = [[QQ(1,2)], [QQ(1), QQ(0)], []]

    >>> dmp_qq_heu_gcd(f, g, 1, QQ)
    ([[1/1], [2/1, 0/1]], [[1/4], [1/2, 0/1]], [[1/2], []])

    """
    result = _dmp_ff_trivial_gcd(f, g, u, K0)

    if result is not None:
        return result

    K1 = K0.get_ring()

    cf, f = dmp_clear_denoms(f, u, K0, K1)
    cg, g = dmp_clear_denoms(g, u, K0, K1)

    f = dmp_convert(f, u, K0, K1)
    g = dmp_convert(g, u, K0, K1)

    h, cff, cfg = dmp_zz_heu_gcd(f, g, u, K1)

    h = dmp_convert(h, u, K1, K0)

    c = dmp_ground_LC(h, u, K0)
    h = dmp_ground_monic(h, u, K0)

    cff = dmp_convert(cff, u, K1, K0)
    cfg = dmp_convert(cfg, u, K1, K0)

    cff = dmp_mul_ground(cff, K0.quo(c, cf), u, K0)
    cfg = dmp_mul_ground(cfg, K0.quo(c, cg), u, K0)

    return h, cff, cfg

def dmp_qq_heu_gcd(f, g, u, K0):
    """
    Heuristic polynomial GCD in `Q[X]`.

    Returns ``(h, cff, cfg)`` such that ``a = gcd(f, g)``,
    ``cff = quo(f, h)``, and ``cfg = quo(g, h)``.

    Examples
    ========

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

    >>> f = QQ(1,4)*x**2 + x*y + y**2
    >>> g = QQ(1,2)*x**2 + x*y

    >>> R.dmp_qq_heu_gcd(f, g)
    (x + 2*y, 1/4*x + 1/2*y, 1/2*x)

    """
    result = _dmp_ff_trivial_gcd(f, g, u, K0)

    if result is not None:
        return result

    K1 = K0.get_ring()

    cf, f = dmp_clear_denoms(f, u, K0, K1)
    cg, g = dmp_clear_denoms(g, u, K0, K1)

    f = dmp_convert(f, u, K0, K1)
    g = dmp_convert(g, u, K0, K1)

    h, cff, cfg = dmp_zz_heu_gcd(f, g, u, K1)

    h = dmp_convert(h, u, K1, K0)

    c = dmp_ground_LC(h, u, K0)
    h = dmp_ground_monic(h, u, K0)

    cff = dmp_convert(cff, u, K1, K0)
    cfg = dmp_convert(cfg, u, K1, K0)

    cff = dmp_mul_ground(cff, K0.quo(c, cf), u, K0)
    cfg = dmp_mul_ground(cfg, K0.quo(c, cg), u, K0)

    return h, cff, cfg