Python densearith.dmp_mul_term函数代码示例

def test_dmp_mul_term():
    assert dmp_mul_term([ZZ(1),ZZ(2),ZZ(3)], ZZ(2), 1, 0, ZZ) == \
           dup_mul_term([ZZ(1),ZZ(2),ZZ(3)], ZZ(2), 1, ZZ)

    assert dmp_mul_term([[]], [ZZ(2)], 3, 1, ZZ) == [[]]
    assert dmp_mul_term([[ZZ(1)]], [], 3, 1, ZZ) == [[]]

    assert dmp_mul_term([[ZZ(1),ZZ(2)], [ZZ(3)]], [ZZ(2)], 2, 1, ZZ) == \
               [[ZZ(2),ZZ(4)], [ZZ(6)], [], []]

    assert dmp_mul_term([[]], [QQ(2,3)], 3, 1, QQ) == [[]]
    assert dmp_mul_term([[QQ(1,2)]], [], 3, 1, QQ) == [[]]

    assert dmp_mul_term([[QQ(1,5),QQ(2,5)], [QQ(3,5)]], [QQ(2,3)], 2, 1, QQ) == \
               [[QQ(2,15),QQ(4,15)], [QQ(6,15)], [], []]

def dmp_rr_prs_gcd(f, g, u, K):
    """
    Computes polynomial GCD using subresultants over a ring.

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

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

    >>> R.dmp_rr_prs_gcd(f, g)
    (x + y, x + y, x)

    """
    if not u:
        return dup_rr_prs_gcd(f, g, K)

    result = _dmp_rr_trivial_gcd(f, g, u, K)

    if result is not None:
        return result

    fc, F = dmp_primitive(f, u, K)
    gc, G = dmp_primitive(g, u, K)

    h = dmp_subresultants(F, G, u, K)[-1]
    c, _, _ = dmp_rr_prs_gcd(fc, gc, u - 1, K)

    if K.is_negative(dmp_ground_LC(h, u, K)):
        h = dmp_neg(h, u, K)

    _, h = dmp_primitive(h, u, K)
    h = dmp_mul_term(h, c, 0, u, K)

    cff = dmp_quo(f, h, u, K)
    cfg = dmp_quo(g, h, u, K)

    return h, cff, cfg

def dmp_rr_prs_gcd(f, g, u, K):
    """
    Computes polynomial GCD using subresultants over a ring.

    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 ZZ
    >>> from sympy.polys.euclidtools import dmp_rr_prs_gcd

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

    >>> dmp_rr_prs_gcd(f, g, 1, ZZ)
    ([[1], [1, 0]], [[1], [1, 0]], [[1], []])

    """
    if not u:
        return dup_rr_prs_gcd(f, g, K)

    result = _dmp_rr_trivial_gcd(f, g, u, K)

    if result is not None:
        return result

    fc, F = dmp_primitive(f, u, K)
    gc, G = dmp_primitive(g, u, K)

    h = dmp_subresultants(F, G, u, K)[-1]
    c, _, _ = dmp_rr_prs_gcd(fc, gc, u-1, K)

    if K.is_negative(dmp_ground_LC(h, u, K)):
        h = dmp_neg(h, u, K)

    _, h = dmp_primitive(h, u, K)
    h = dmp_mul_term(h, c, 0, u, K)

    cff = dmp_quo(f, h, u, K)
    cfg = dmp_quo(g, h, u, K)

    return h, cff, cfg

def dmp_ff_prs_gcd(f, g, u, K):
    """
    Computes polynomial GCD using subresultants over a field.

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

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

    """
    if not u:
        return dup_ff_prs_gcd(f, g, K)

    result = _dmp_ff_trivial_gcd(f, g, u, K)

    if result is not None:
        return result

    fc, F = dmp_primitive(f, u, K)
    gc, G = dmp_primitive(g, u, K)

    h = dmp_subresultants(F, G, u, K)[-1]
    c, _, _ = dmp_ff_prs_gcd(fc, gc, u - 1, K)

    _, h = dmp_primitive(h, u, K)
    h = dmp_mul_term(h, c, 0, u, K)
    h = dmp_ground_monic(h, u, K)

    cff = dmp_quo(f, h, u, K)
    cfg = dmp_quo(g, h, u, K)

    return h, cff, cfg

def dmp_ff_prs_gcd(f, g, u, K):
    """
    Computes polynomial GCD using subresultants over a field.

    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_ff_prs_gcd

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

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

    """
    if not u:
        return dup_ff_prs_gcd(f, g, K)

    result = _dmp_ff_trivial_gcd(f, g, u, K)

    if result is not None:
        return result

    fc, F = dmp_primitive(f, u, K)
    gc, G = dmp_primitive(g, u, K)

    h = dmp_subresultants(F, G, u, K)[-1]
    c, _, _ = dmp_ff_prs_gcd(fc, gc, u-1, K)

    _, h = dmp_primitive(h, u, K)
    h = dmp_mul_term(h, c, 0, u, K)
    h = dmp_ground_monic(h, u, K)

    cff = dmp_quo(f, h, u, K)
    cfg = dmp_quo(g, h, u, K)

    return h, cff, cfg

def dmp_inner_subresultants(f, g, u, K):
    """
    Subresultant PRS algorithm in ``K[X]``.

    **Examples**

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

    >>> f = ZZ.map([[3, 0], [], [-1, 0, 0, -4]])
    >>> g = ZZ.map([[1], [1, 0, 0, 0], [-9]])

    >>> a = [[3, 0, 0, 0, 0], [1, 0, -27, 4]]
    >>> b = [[-3, 0, 0, -12, 1, 0, -54, 8, 729, -216, 16]]

    >>> R = ZZ.map([f, g, a, b])
    >>> B = ZZ.map([[-1], [1], [9, 0, 0, 0, 0, 0, 0, 0, 0]])
    >>> D = ZZ.map([0, 1, 1])

    >>> dmp_inner_subresultants(f, g, 1, ZZ) == (R, B, D)
    True

    """
    if not u:
        return dup_inner_subresultants(f, g, K)

    n = dmp_degree(f, u)
    m = dmp_degree(g, u)

    if n < m:
        f, g = g, f
        n, m = m, n

    R = [f, g]
    d = n - m
    v = u - 1

    b = dmp_pow(dmp_ground(-K.one, v), d+1, v, K)
    c = dmp_ground(-K.one, v)

    B, D = [b], [d]

    if dmp_zero_p(f, u) or dmp_zero_p(g, u):
        return R, B, D

    h = dmp_prem(f, g, u, K)
    h = dmp_mul_term(h, b, 0, u, K)

    while not dmp_zero_p(h, u):
        k = dmp_degree(h, u)
        R.append(h)

        lc = dmp_LC(g, K)

        p = dmp_pow(dmp_neg(lc, v, K), d, v, K)

        if not d:
            q = c
        else:
            q = dmp_pow(c, d-1, v, K)

        c = dmp_exquo(p, q, v, K)
        b = dmp_mul(dmp_neg(lc, v, K),
                    dmp_pow(c, m-k, v, K), v, K)

        f, g, m, d = g, h, k, m-k

        B.append(b)
        D.append(d)

        h = dmp_prem(f, g, u, K)
        h = [ dmp_exquo(ch, b, v, K) for ch in h ]

    return R, B, D

def dmp_inner_subresultants(f, g, u, K):
    """
    Subresultant PRS algorithm in `K[X]`.

    Examples
    ========

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

    >>> f = 3*x**2*y - y**3 - 4
    >>> g = x**2 + x*y**3 - 9

    >>> a = 3*x*y**4 + y**3 - 27*y + 4
    >>> b = -3*y**10 - 12*y**7 + y**6 - 54*y**4 + 8*y**3 + 729*y**2 - 216*y + 16

    >>> prs = [f, g, a, b]
    >>> sres = [[1], [1], [3, 0, 0, 0, 0], [-3, 0, 0, -12, 1, 0, -54, 8, 729, -216, 16]]

    >>> R.dmp_inner_subresultants(f, g) == (prs, sres)
    True

    """
    if not u:
        return dup_inner_subresultants(f, g, K)

    n = dmp_degree(f, u)
    m = dmp_degree(g, u)

    if n < m:
        f, g = g, f
        n, m = m, n

    if dmp_zero_p(f, u):
        return [], []

    v = u - 1
    if dmp_zero_p(g, u):
        return [f], [dmp_ground(K.one, v)]

    R = [f, g]
    d = n - m

    b = dmp_pow(dmp_ground(-K.one, v), d + 1, v, K)

    h = dmp_prem(f, g, u, K)
    h = dmp_mul_term(h, b, 0, u, K)

    lc = dmp_LC(g, K)
    c = dmp_pow(lc, d, v, K)

    S = [dmp_ground(K.one, v), c]
    c = dmp_neg(c, v, K)

    while not dmp_zero_p(h, u):
        k = dmp_degree(h, u)
        R.append(h)

        f, g, m, d = g, h, k, m - k

        b = dmp_mul(dmp_neg(lc, v, K),
                    dmp_pow(c, d, v, K), v, K)

        h = dmp_prem(f, g, u, K)
        h = [ dmp_quo(ch, b, v, K) for ch in h ]

        lc = dmp_LC(g, K)

        if d > 1:
            p = dmp_pow(dmp_neg(lc, v, K), d, v, K)
            q = dmp_pow(c, d - 1, v, K)
            c = dmp_quo(p, q, v, K)
        else:
            c = dmp_neg(lc, v, K)

        S.append(dmp_neg(c, v, K))

    return R, S

def dmp_inner_subresultants(f, g, u, K):
    """
    Subresultant PRS algorithm in `K[X]`.

    Examples
    ========

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

    >>> f = 3*x**2*y - y**3 - 4
    >>> g = x**2 + x*y**3 - 9

    >>> a = 3*x*y**4 + y**3 - 27*y + 4
    >>> b = -3*y**10 - 12*y**7 + y**6 - 54*y**4 + 8*y**3 + 729*y**2 - 216*y + 16

    >>> prs = [f, g, a, b]
    >>> beta = [[-1], [1], [9, 0, 0, 0, 0, 0, 0, 0, 0]]
    >>> delta = [0, 1, 1]

    >>> R.dmp_inner_subresultants(f, g) == (prs, beta, delta)
    True

    """
    if not u:
        return dup_inner_subresultants(f, g, K)

    n = dmp_degree(f, u)
    m = dmp_degree(g, u)

    if n < m:
        f, g = g, f
        n, m = m, n

    R = [f, g]
    d = n - m
    v = u - 1

    b = dmp_pow(dmp_ground(-K.one, v), d + 1, v, K)
    c = dmp_ground(-K.one, v)

    B, D = [b], [d]

    if dmp_zero_p(f, u) or dmp_zero_p(g, u):
        return R, B, D

    h = dmp_prem(f, g, u, K)
    h = dmp_mul_term(h, b, 0, u, K)

    while not dmp_zero_p(h, u):
        k = dmp_degree(h, u)
        R.append(h)

        lc = dmp_LC(g, K)

        p = dmp_pow(dmp_neg(lc, v, K), d, v, K)

        if not d:
            q = c
        else:
            q = dmp_pow(c, d - 1, v, K)

        c = dmp_quo(p, q, v, K)
        b = dmp_mul(dmp_neg(lc, v, K),
                    dmp_pow(c, m - k, v, K), v, K)

        f, g, m, d = g, h, k, m - k

        B.append(b)
        D.append(d)

        h = dmp_prem(f, g, u, K)

        h = [ dmp_quo(ch, b, v, K) for ch in h ]

    return R, B, D