Ejemplo n.º 1
0
def dmp_fateman_poly_F_1(n, K):
    """Fateman's GCD benchmark: trivial GCD """
    u = [K(1), K(0)]

    for i in range(0, n):
        u = [dmp_one(i, K), u]

    v = [K(1), K(0), K(0)]

    for i in range(0, n):
        v = [dmp_one(i, K), dmp_zero(i), v]

    m = n - 1

    U = dmp_add_term(u, dmp_ground(K(1), m), 0, n, K)
    V = dmp_add_term(u, dmp_ground(K(2), m), 0, n, K)

    f = [[-K(3), K(0)], [], [K(1), K(0), -K(1)]]

    W = dmp_add_term(v, dmp_ground(K(1), m), 0, n, K)
    Y = dmp_raise(f, m, 1, K)

    F = dmp_mul(U, V, n, K)
    G = dmp_mul(W, Y, n, K)

    H = dmp_one(n, K)

    return F, G, H
Ejemplo n.º 2
0
def _dmp_inner_gcd(f, g, u, K):
    """Helper function for `dmp_inner_gcd()`. """
    if not K.is_Exact:
        try:
            exact = K.get_exact()
        except DomainError:
            return dmp_one(u, K), f, g

        f = dmp_convert(f, u, K, exact)
        g = dmp_convert(g, u, K, exact)

        h, cff, cfg = _dmp_inner_gcd(f, g, u, exact)

        h = dmp_convert(h, u, exact, K)
        cff = dmp_convert(cff, u, exact, K)
        cfg = dmp_convert(cfg, u, exact, K)

        return h, cff, cfg
    elif K.has_Field:
        if K.is_QQ and query('USE_HEU_GCD'):
            try:
                return dmp_qq_heu_gcd(f, g, u, K)
            except HeuristicGCDFailed:
                pass

        return dmp_ff_prs_gcd(f, g, u, K)
    else:
        if K.is_ZZ and query('USE_HEU_GCD'):
            try:
                return dmp_zz_heu_gcd(f, g, u, K)
            except HeuristicGCDFailed:
                pass

        return dmp_rr_prs_gcd(f, g, u, K)
Ejemplo n.º 3
0
def dmp_fateman_poly_F_3(n, K):
    """Fateman's GCD benchmark: sparse inputs (deg f ~ vars f) """
    u = dup_from_raw_dict({n + 1: K.one}, K)

    for i in range(0, n - 1):
        u = dmp_add_term([u], dmp_one(i, K), n + 1, i + 1, K)

    v = dmp_add_term(u, dmp_ground(K(2), n - 2), 0, n, K)

    f = dmp_sqr(
        dmp_add_term([dmp_neg(v, n - 1, K)], dmp_one(n - 1, K), n + 1, n, K),
        n, K)
    g = dmp_sqr(dmp_add_term([v], dmp_one(n - 1, K), n + 1, n, K), n, K)

    v = dmp_add_term(u, dmp_one(n - 2, K), 0, n - 1, K)

    h = dmp_sqr(dmp_add_term([v], dmp_one(n - 1, K), n + 1, n, K), n, K)

    return dmp_mul(f, h, n, K), dmp_mul(g, h, n, K), h
Ejemplo n.º 4
0
def dmp_fateman_poly_F_2(n, K):
    """Fateman's GCD benchmark: linearly dense quartic inputs """
    u = [K(1), K(0)]

    for i in range(0, n - 1):
        u = [dmp_one(i, K), u]

    m = n - 1

    v = dmp_add_term(u, dmp_ground(K(2), m - 1), 0, n, K)

    f = dmp_sqr([dmp_one(m, K), dmp_neg(v, m, K)], n, K)
    g = dmp_sqr([dmp_one(m, K), v], n, K)

    v = dmp_add_term(u, dmp_one(m - 1, K), 0, n, K)

    h = dmp_sqr([dmp_one(m, K), v], n, K)

    return dmp_mul(f, h, n, K), dmp_mul(g, h, n, K), h
Ejemplo n.º 5
0
def _dmp_rr_trivial_gcd(f, g, u, K):
    """Handle trivial cases in GCD algorithm over a ring. """
    zero_f = dmp_zero_p(f, u)
    zero_g = dmp_zero_p(g, u)

    if zero_f and zero_g:
        return tuple(dmp_zeros(3, u, K))
    elif zero_f:
        if K.is_nonnegative(dmp_ground_LC(g, u, K)):
            return g, dmp_zero(u), dmp_one(u, K)
        else:
            return dmp_neg(g, u, K), dmp_zero(u), dmp_ground(-K.one, u)
    elif zero_g:
        if K.is_nonnegative(dmp_ground_LC(f, u, K)):
            return f, dmp_one(u, K), dmp_zero(u)
        else:
            return dmp_neg(f, u, K), dmp_ground(-K.one, u), dmp_zero(u)
    elif dmp_one_p(f, u, K) or dmp_one_p(g, u, K):
        return dmp_one(u, K), f, g
    elif query('USE_SIMPLIFY_GCD'):
        return _dmp_simplify_gcd(f, g, u, K)
Ejemplo n.º 6
0
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(range(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
Ejemplo n.º 7
0
def dmp_zz_wang_hensel_lifting(f, H, LC, A, p, u, K):
    """Wang/EEZ: Parallel Hensel lifting algorithm. """
    S, n, v = [f], len(A), u - 1

    H = list(H)

    for i, a in enumerate(reversed(A[1:])):
        s = dmp_eval_in(S[0], a, n - i, u - i, K)
        S.insert(0, dmp_ground_trunc(s, p, v - i, K))

    d = max(dmp_degree_list(f, u)[1:])

    for j, s, a in zip(range(2, n + 2), S, A):
        G, w = list(H), j - 1

        I, J = A[:j - 2], A[j - 1:]

        for i, (h, lc) in enumerate(zip(H, LC)):
            lc = dmp_ground_trunc(dmp_eval_tail(lc, J, v, K), p, w - 1, K)
            H[i] = [lc] + dmp_raise(h[1:], 1, w - 1, K)

        m = dmp_nest([K.one, -a], w, K)
        M = dmp_one(w, K)

        c = dmp_sub(s, dmp_expand(H, w, K), w, K)

        dj = dmp_degree_in(s, w, w)

        for k in K.map(range(0, dj)):
            if dmp_zero_p(c, w):
                break

            M = dmp_mul(M, m, w, K)
            C = dmp_diff_eval_in(c, k + 1, a, w, w, K)

            if not dmp_zero_p(C, w - 1):
                C = dmp_quo_ground(C, K.factorial(k + 1), w - 1, K)
                T = dmp_zz_diophantine(G, C, I, d, p, w - 1, K)

                for i, (h, t) in enumerate(zip(H, T)):
                    h = dmp_add_mul(h, dmp_raise(t, 1, w - 1, K), M, w, K)
                    H[i] = dmp_ground_trunc(h, p, w, K)

                h = dmp_sub(s, dmp_expand(H, w, K), w, K)
                c = dmp_ground_trunc(h, p, w, K)

    if dmp_expand(H, u, K) != f:
        raise ExtraneousFactors  # pragma: no cover
    else:
        return H
Ejemplo n.º 8
0
def dmp_pow(f, n, u, K):
    """
    Raise ``f`` to the ``n``-th power in ``K[X]``.

    Examples
    ========

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

    >>> R.dmp_pow(x*y + 1, 3)
    x**3*y**3 + 3*x**2*y**2 + 3*x*y + 1
    """
    if not u:
        return dup_pow(f, n, K)

    if not n:
        return dmp_one(u, K)
    if n < 0:
        raise ValueError("can't raise polynomial to a negative power")
    if n == 1 or dmp_zero_p(f, u) or dmp_one_p(f, u, K):
        return f

    g = dmp_one(u, K)

    while True:
        n, m = n//2, n

        if m & 1:
            g = dmp_mul(g, f, u, K)

            if not n:
                break

        f = dmp_sqr(f, u, K)

    return g
Ejemplo n.º 9
0
def dmp_expand(polys, u, K):
    """
    Multiply together several polynomials in ``K[X]``.

    Examples
    ========

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

    >>> R.dmp_expand([x**2 + y**2, x + 1])
    x**3 + x**2 + x*y**2 + y**2
    """
    if not polys:
        return dmp_one(u, K)

    f = polys[0]

    for g in polys[1:]:
        f = dmp_mul(f, g, u, K)

    return f
Ejemplo n.º 10
0
def test_dmp_one():
    assert dmp_one(0, ZZ) == [ZZ(1)]
    assert dmp_one(2, ZZ) == [[[ZZ(1)]]]
Ejemplo n.º 11
0
def dmp_zz_diophantine(F, c, A, d, p, u, K):
    """Wang/EEZ: Solve multivariate Diophantine equations. """
    if not A:
        S = [[] for _ in F]
        n = dup_degree(c)

        for i, coeff in enumerate(c):
            if not coeff:
                continue

            T = dup_zz_diophantine(F, n - i, p, K)

            for j, (s, t) in enumerate(zip(S, T)):
                t = dup_mul_ground(t, coeff, K)
                S[j] = dup_trunc(dup_add(s, t, K), p, K)
    else:
        n = len(A)
        e = dmp_expand(F, u, K)

        a, A = A[-1], A[:-1]
        B, G = [], []

        for f in F:
            B.append(dmp_quo(e, f, u, K))
            G.append(dmp_eval_in(f, a, n, u, K))

        C = dmp_eval_in(c, a, n, u, K)

        v = u - 1

        S = dmp_zz_diophantine(G, C, A, d, p, v, K)
        S = [dmp_raise(s, 1, v, K) for s in S]

        for s, b in zip(S, B):
            c = dmp_sub_mul(c, s, b, u, K)

        c = dmp_ground_trunc(c, p, u, K)

        m = dmp_nest([K.one, -a], n, K)
        M = dmp_one(n, K)

        for k in K.map(range(0, d)):
            if dmp_zero_p(c, u):
                break

            M = dmp_mul(M, m, u, K)
            C = dmp_diff_eval_in(c, k + 1, a, n, u, K)

            if not dmp_zero_p(C, v):
                C = dmp_quo_ground(C, K.factorial(k + 1), v, K)
                T = dmp_zz_diophantine(G, C, A, d, p, v, K)

                for i, t in enumerate(T):
                    T[i] = dmp_mul(dmp_raise(t, 1, v, K), M, u, K)

                for i, (s, t) in enumerate(zip(S, T)):
                    S[i] = dmp_add(s, t, u, K)

                for t, b in zip(T, B):
                    c = dmp_sub_mul(c, t, b, u, K)

                c = dmp_ground_trunc(c, p, u, K)

        S = [dmp_ground_trunc(s, p, u, K) for s in S]

    return S