Ejemplo n.º 1
0
void _fmpz_poly_hensel_lift_without_inverse(fmpz *G, fmpz *H, 
    const fmpz *f, long lenF, 
    const fmpz *g, long lenG, const fmpz *h, long lenH, 
    const fmpz *a, long lenA, const fmpz *b, long lenB, 
    const fmpz_t p, const fmpz_t p1)
{
    const fmpz one[1] = {1l};
    const long lenM = FLINT_MAX(lenG, lenH);
    const long lenE = FLINT_MAX(lenG + lenB - 2, lenH + lenA - 2);
    const long lenD = FLINT_MAX(lenE, lenF);
    fmpz *C, *D, *E, *M;

    C = _fmpz_vec_init(lenF + lenD + lenE + lenM);
    D = C + lenF;
    E = D + lenD;
    M = E + lenE;

    if (lenG >= lenH)
        _fmpz_poly_mul(C, g,lenG, h, lenH);
    else
        _fmpz_poly_mul(C, h, lenH, g, lenG);
    _fmpz_vec_sub(C, f, C, lenF);
    _fmpz_vec_scalar_divexact_fmpz(D, C, lenF, p);
    _fmpz_vec_scalar_mod_fmpz(C, D, lenF, p1);

    lift(G, g, lenG, b, lenB);

    lift(H, h, lenH, a, lenA);

    _fmpz_vec_clear(C, lenF + lenD + lenE + lenM);
}
Ejemplo n.º 2
0
/* 
   Returns 1 if sign * (G, glen) * (Q, qlen) = (P, len), else returns 0.
   Temp requires space for glen + qlen - 1 coefficients
*/
int multiplies_out(fmpz * P, long len, const fmpz * Q, long qlen, 
                   const fmpz * G, long glen, long sign, fmpz * temp)
{
   int divides = 0;

   /* multiply out */
   if (qlen >= glen)
      _fmpz_poly_mul(temp, Q, qlen, G, glen);
   else
      _fmpz_poly_mul(temp, G, glen, Q, qlen);
   if (sign < 0L) _fmpz_vec_neg(temp, temp, glen + qlen - 1);

   /* check if quotient really was exact */
   divides = (glen + qlen - 1 == len && _fmpz_vec_equal(temp, P, len));

   return divides;
}
Ejemplo n.º 3
0
void _qadic_exp_balanced(fmpz *rop, const fmpz *x, slong v, slong len, 
                         const fmpz *a, const slong *j, slong lena, 
                         const fmpz_t p, slong N, const fmpz_t pN)
{
    const slong d = j[lena - 1];

    fmpz_t pw;
    fmpz *r, *s, *t;
    slong i, w;

    r = _fmpz_vec_init(d);
    s = _fmpz_vec_init(2*d - 1);
    t = _fmpz_vec_init(d);
    fmpz_init(pw);

    fmpz_pow_ui(pw, p, v);
    _fmpz_vec_scalar_mul_fmpz(t, x, len, pw);
    _fmpz_vec_scalar_mod_fmpz(t, t, len, pN);
    _fmpz_vec_zero(t + len, d - len);

    fmpz_set(pw, p);
    fmpz_one(rop + 0);
    _fmpz_vec_zero(rop + 1, d - 1);
    w = 1;

    while (!_fmpz_vec_is_zero(t, d))
    {
        fmpz_mul(pw, pw, pw);

        for (i = 0; i < d; i++)
        {
            fmpz_fdiv_r(r + i, t + i, pw);
            fmpz_sub(t + i, t + i, r + i);
        }

        if (!_fmpz_vec_is_zero(r, d))
        {
            _qadic_exp_bsplit(r, r, w, d, a, j, lena, p, N);
            _fmpz_poly_mul(s, rop, d, r, d);
            _fmpz_poly_reduce(s, 2*d - 1, a, j, lena);
            _fmpz_vec_scalar_mod_fmpz(rop, s, d, pN);
        }

        w *= 2;
    }

    _fmpz_vec_clear(r, d);
    _fmpz_vec_clear(s, 2*d - 1);
    _fmpz_vec_clear(t, d);
    fmpz_clear(pw);
}
Ejemplo n.º 4
0
void
_gamma_rf_bsplit(fmpz * A, ulong a, ulong b)
{
    ulong n = b - a;

    if (n == 0)
    {
        fmpz_one(A);
    }
    else if (n < 8)
    {
        ulong j, k;

        fmpz_set_ui(A, a);
        fmpz_one(A + 1);

        for (j = 1; j < n; j++)
        {
            fmpz_one(A + j + 1);

            for (k = j; k > 0; k--)
            {
                fmpz_mul_ui(A + k, A + k, a + j);
                fmpz_add(A + k, A + k, A + k - 1);
            }

            fmpz_mul_ui(A, A, a + j);
        }
    }
    else
    {
        ulong m = a + (b - a) / 2;
        ulong w = m - a;
        ulong v = b - m;

        fmpz *t, *A1, *A2;

        t = _fmpz_vec_init(w + v + 2);

        A1 = t;
        A2 = A1 + w + 1;

        _gamma_rf_bsplit(A1, a, m);
        _gamma_rf_bsplit(A2, m, b);

        _fmpz_poly_mul(A, A2, v + 1, A1, w + 1);

        _fmpz_vec_clear(t, w + v + 2);
    }
}
Ejemplo n.º 5
0
/* Balanced product of linear factors (x+alpha_i) using
   fixed-point arithmetic with prec bits */
static void
balanced_product(fmpz * c, fmpz * alpha, slong len, slong prec)
{
    if (len == 1)
    {
        fmpz_one(c + 1);
        fmpz_mul_2exp(c + 1, c + 1, prec);
        fmpz_set(c, alpha);
    }
    else if (len == 2)
    {
        fmpz_mul(c, alpha, alpha + 1);
        fmpz_fdiv_q_2exp(c, c, prec);
        fmpz_add(c + 1, alpha, alpha + 1);
        fmpz_one(c + 2);
        fmpz_mul_2exp(c + 2, c + 2, prec);
    }
    else
    {
        fmpz *L, *R;
        slong i, m;

        m = len / 2;
        L = _fmpz_vec_init(len + 2);
        R = L + m + 1;

        balanced_product(L, alpha, m, prec);
        balanced_product(R, alpha + m, len - m, prec);
        _fmpz_poly_mul(c, R, len - m + 1, L, m + 1);

        for (i = 0; i < len + 1; i++)
            fmpz_fdiv_q_2exp(c + i, c + i, prec);

        _fmpz_vec_clear(L, len + 2);
    }
}
Ejemplo n.º 6
0
void
_fmpz_poly_compose_divconquer(fmpz * res, const fmpz * poly1, long len1, 
                                          const fmpz * poly2, long len2)
{
    long i, j, k, n;
    long *hlen, alloc, powlen;
    fmpz *v, **h, *pow, *temp;
    
    if (len1 == 1)
    {
        fmpz_set(res, poly1);
        return;
    }
    if (len2 == 1)
    {
        _fmpz_poly_evaluate_fmpz(res, poly1, len1, poly2);
        return;
    }
    if (len1 == 2)
    {
        _fmpz_poly_compose_horner(res, poly1, len1, poly2, len2);
        return;
    }

    /* Initialisation */
    
    hlen = (long *) malloc(((len1 + 1) / 2) * sizeof(long));
    
    for (k = 1; (2 << k) < len1; k++) ;
    
    hlen[0] = hlen[1] = ((1 << k) - 1) * (len2 - 1) + 1;
    for (i = k - 1; i > 0; i--)
    {
        long hi = (len1 + (1 << i) - 1) / (1 << i);
        for (n = (hi + 1) / 2; n < hi; n++)
            hlen[n] = ((1 << i) - 1) * (len2 - 1) + 1;
    }
    powlen = (1 << k) * (len2 - 1) + 1;
    
    alloc = 0;
    for (i = 0; i < (len1 + 1) / 2; i++)
        alloc += hlen[i];

    v = _fmpz_vec_init(alloc +  2 * powlen);
    h = (fmpz **) malloc(((len1 + 1) / 2) * sizeof(fmpz *));
    h[0] = v;
    for (i = 0; i < (len1 - 1) / 2; i++)
    {
        h[i + 1] = h[i] + hlen[i];
        hlen[i]  = 0;
    }
    hlen[(len1 - 1) / 2] = 0;
    pow  = v + alloc;
    temp = pow + powlen;
    
    /* Let's start the actual work */
    
    for (i = 0, j = 0; i < len1 / 2; i++, j += 2)
    {
        if (poly1[j + 1] != 0L)
        {
            _fmpz_vec_scalar_mul_fmpz(h[i], poly2, len2, poly1 + j + 1);
            fmpz_add(h[i], h[i], poly1 + j);
            hlen[i] = len2;
        }
        else if (poly1[j] != 0L)
        {
            fmpz_set(h[i], poly1 + j);
            hlen[i] = 1;
        }
    }
    if ((len1 & 1L))
    {
        if (poly1[j] != 0L)
        {
            fmpz_set(h[i], poly1 + j);
            hlen[i] = 1;
        }
    }
    
    _fmpz_poly_mul(pow, poly2, len2, poly2, len2);
    powlen = 2 * len2 - 1;
    
    for (n = (len1 + 1) / 2; n > 2; n = (n + 1) / 2)
    {
        if (hlen[1] > 0)
        {
            long templen = powlen + hlen[1] - 1;
            _fmpz_poly_mul(temp, pow, powlen, h[1], hlen[1]);
            _fmpz_poly_add(h[0], temp, templen, h[0], hlen[0]);
            hlen[0] = FLINT_MAX(hlen[0], templen);
        }
        
        for (i = 1; i < n / 2; i++)
        {
            if (hlen[2*i + 1] > 0)
            {
                _fmpz_poly_mul(h[i], pow, powlen, h[2*i + 1], hlen[2*i + 1]);
                hlen[i] = hlen[2*i + 1] + powlen - 1;
            } else
                hlen[i] = 0;
            _fmpz_poly_add(h[i], h[i], hlen[i], h[2*i], hlen[2*i]);
            hlen[i] = FLINT_MAX(hlen[i], hlen[2*i]);
        }
        if ((n & 1L))
        {
            _fmpz_vec_set(h[i], h[2*i], hlen[2*i]);
            hlen[i] = hlen[2*i];
        }
        
        _fmpz_poly_mul(temp, pow, powlen, pow, powlen);
        powlen += powlen - 1;
        {
            fmpz * t = pow;
            pow      = temp;
            temp     = t;
        }
    }

    _fmpz_poly_mul(res, pow, powlen, h[1], hlen[1]);
    _fmpz_vec_add(res, res, h[0], hlen[0]);
    
    _fmpz_vec_clear(v, alloc + 2 * powlen);
    free(h);
    free(hlen);
}
Ejemplo n.º 7
0
void frob(const mpoly_t P, const ctx_t ctxFracQt,
          const qadic_t t1, const qadic_ctx_t Qq,
          prec_t *prec, const prec_t *prec_in,
          int verbose)
{
    const padic_ctx_struct *Qp = &Qq->pctx;
    const fmpz *p = Qp->p;
    const long a  = qadic_ctx_degree(Qq);
    const long n  = P->n - 1;
    const long d  = mpoly_degree(P, -1, ctxFracQt);
    const long b  = gmc_basis_size(n, d);

    long i, j, k;

    /* Diagonal fibre */
    padic_mat_t F0;

    /* Gauss--Manin Connection */
    mat_t M;
    mon_t *bR, *bC;
    fmpz_poly_t r;

    /* Local solution */
    fmpz_poly_mat_t C, Cinv;
    long vC, vCinv;

    /* Frobenius */
    fmpz_poly_mat_t F;
    long vF;

    fmpz_poly_mat_t F1;
    long vF1;

    fmpz_poly_t cp;

    clock_t c0, c1;
    double c;

    if (verbose)
    {
        printf("Input:\n");
        printf("  P  = "), mpoly_print(P, ctxFracQt), printf("\n");
        printf("  p  = "), fmpz_print(p), printf("\n");
        printf("  t1 = "), qadic_print_pretty(t1, Qq), printf("\n");
        printf("\n");
        fflush(stdout);
    }

    /* Step 1 {M, r} *********************************************************/

    c0 = clock();

    mat_init(M, b, b, ctxFracQt);
    fmpz_poly_init(r);

    gmc_compute(M, &bR, &bC, P, ctxFracQt);

    {
        fmpz_poly_t t;

        fmpz_poly_init(t);
        fmpz_poly_set_ui(r, 1);
        for (i = 0; i < M->m; i++)
            for (j = 0; j < M->n; j++)
            {
                fmpz_poly_lcm(t, r, fmpz_poly_q_denref(
                                  (fmpz_poly_q_struct *) mat_entry(M, i, j, ctxFracQt)));
                fmpz_poly_swap(r, t);
            }
        fmpz_poly_clear(t);
    }

    c1 = clock();
    c  = (double) (c1 - c0) / CLOCKS_PER_SEC;

    if (verbose)
    {
        printf("Gauss-Manin connection:\n");
        printf("  r(t) = "), fmpz_poly_print_pretty(r, "t"), printf("\n");
        printf("  Time = %f\n", c);
        printf("\n");
        fflush(stdout);
    }

    {
        qadic_t t;

        qadic_init2(t, 1);
        fmpz_poly_evaluate_qadic(t, r, t1, Qq);

        if (qadic_is_zero(t))
        {
            printf("Exception (deformation_frob).\n");
            printf("The resultant r evaluates to zero (mod p) at t1.\n");
            abort();
        }
        qadic_clear(t);
    }

    /* Precisions ************************************************************/

    if (prec_in != NULL)
    {
        *prec = *prec_in;
    }
    else
    {
        deformation_precisions(prec, p, a, n, d, fmpz_poly_degree(r));
    }

    if (verbose)
    {
        printf("Precisions:\n");
        printf("  N0   = %ld\n", prec->N0);
        printf("  N1   = %ld\n", prec->N1);
        printf("  N2   = %ld\n", prec->N2);
        printf("  N3   = %ld\n", prec->N3);
        printf("  N3i  = %ld\n", prec->N3i);
        printf("  N3w  = %ld\n", prec->N3w);
        printf("  N3iw = %ld\n", prec->N3iw);
        printf("  N4   = %ld\n", prec->N4);
        printf("  m    = %ld\n", prec->m);
        printf("  K    = %ld\n", prec->K);
        printf("  r    = %ld\n", prec->r);
        printf("  s    = %ld\n", prec->s);
        printf("\n");
        fflush(stdout);
    }

    /* Initialisation ********************************************************/

    padic_mat_init2(F0, b, b, prec->N4);

    fmpz_poly_mat_init(C, b, b);
    fmpz_poly_mat_init(Cinv, b, b);

    fmpz_poly_mat_init(F, b, b);
    vF = 0;

    fmpz_poly_mat_init(F1, b, b);
    vF1 = 0;

    fmpz_poly_init(cp);

    /* Step 2 {F0} ***********************************************************/

    {
        padic_ctx_t pctx_F0;
        fmpz *t;

        padic_ctx_init(pctx_F0, p, FLINT_MIN(prec->N4 - 10, 0), prec->N4, PADIC_VAL_UNIT);
        t = _fmpz_vec_init(n + 1);

        c0 = clock();

        mpoly_diagonal_fibre(t, P, ctxFracQt);

        diagfrob(F0, t, n, d, prec->N4, pctx_F0, 0);
        padic_mat_transpose(F0, F0);

        c1 = clock();
        c  = (double) (c1 - c0) / CLOCKS_PER_SEC;

        if (verbose)
        {
            printf("Diagonal fibre:\n");
            printf("  P(0) = {"), _fmpz_vec_print(t, n + 1), printf("}\n");
            printf("  Time = %f\n", c);
            printf("\n");
            fflush(stdout);
        }

        _fmpz_vec_clear(t, n + 1);
        padic_ctx_clear(pctx_F0);
    }

    /* Step 3 {C, Cinv} ******************************************************/
    /*
        Compute C as a matrix over Z_p[[t]].  A is the same but as a series
        of matrices over Z_p.  Mt is the matrix -M^t, and Cinv is C^{-1}^t,
        the local solution of the differential equation replacing M by Mt.
     */

    c0 = clock();
    {
        const long K = prec->K;
        padic_mat_struct *A;

        gmde_solve(&A, K, p, prec->N3, prec->N3w, M, ctxFracQt);
        gmde_convert_soln(C, &vC, A, K, p);

        for(i = 0; i < K; i++)
            padic_mat_clear(A + i);
        free(A);
    }
    c1 = clock();
    c  = (double) (c1 - c0) / CLOCKS_PER_SEC;
    if (verbose)
    {
        printf("Local solution:\n");
        printf("  Time for C      = %f\n", c);
        fflush(stdout);
    }

    c0 = clock();
    {
        const long K = (prec->K + (*p) - 1) / (*p);
        mat_t Mt;
        padic_mat_struct *Ainv;

        mat_init(Mt, b, b, ctxFracQt);
        mat_transpose(Mt, M, ctxFracQt);
        mat_neg(Mt, Mt, ctxFracQt);
        gmde_solve(&Ainv, K, p, prec->N3i, prec->N3iw, Mt, ctxFracQt);
        gmde_convert_soln(Cinv, &vCinv, Ainv, K, p);

        fmpz_poly_mat_transpose(Cinv, Cinv);
        fmpz_poly_mat_compose_pow(Cinv, Cinv, *p);

        for(i = 0; i < K; i++)
            padic_mat_clear(Ainv + i);
        free(Ainv);
        mat_clear(Mt, ctxFracQt);
    }
    c1 = clock();
    c  = (double) (c1 - c0) / CLOCKS_PER_SEC;
    if (verbose)
    {
        printf("  Time for C^{-1} = %f\n", c);
        printf("\n");
        fflush(stdout);
    }

    /* Step 4 {F(t) := C(t) F(0) C(t^p)^{-1}} ********************************/
    /*
        Computes the product C(t) F(0) C(t^p)^{-1} modulo (p^{N_2}, t^K).
        This is done by first computing the unit part of the product
        exactly over the integers modulo t^K.
     */

    c0 = clock();
    {
        fmpz_t pN;
        fmpz_poly_mat_t T;

        fmpz_init(pN);
        fmpz_poly_mat_init(T, b, b);

        for (i = 0; i < b; i++)
        {
            /* Find the unique k s.t. F0(i,k) is non-zero */
            for (k = 0; k < b; k++)
                if (!fmpz_is_zero(padic_mat_entry(F0, i, k)))
                    break;
            if (k == b)
            {
                printf("Exception (frob). F0 is singular.\n\n");
                abort();
            }

            for (j = 0; j < b; j++)
            {
                fmpz_poly_scalar_mul_fmpz(fmpz_poly_mat_entry(T, i, j),
                                          fmpz_poly_mat_entry(Cinv, k, j),
                                          padic_mat_entry(F0, i, k));
            }
        }

        fmpz_poly_mat_mul(F, C, T);
        fmpz_poly_mat_truncate(F, prec->K);
        vF = vC + padic_mat_val(F0) + vCinv;

        /* Canonicalise (F, vF) */
        {
            long v = fmpz_poly_mat_ord_p(F, p);

            if (v == LONG_MAX)
            {
                printf("ERROR (deformation_frob).  F(t) == 0.\n");
                abort();
            }
            else if (v > 0)
            {
                fmpz_pow_ui(pN, p, v);
                fmpz_poly_mat_scalar_divexact_fmpz(F, F, pN);
                vF = vF + v;
            }
        }

        /* Reduce (F, vF) modulo p^{N2} */
        fmpz_pow_ui(pN, p, prec->N2 - vF);
        fmpz_poly_mat_scalar_mod_fmpz(F, F, pN);

        fmpz_clear(pN);
        fmpz_poly_mat_clear(T);
    }
    c1 = clock();
    c  = (double) (c1 - c0) / CLOCKS_PER_SEC;
    if (verbose)
    {
        printf("Matrix for F(t):\n");
        printf("  Time = %f\n", c);
        printf("\n");
        fflush(stdout);
    }

    /* Step 5 {G = r(t)^m F(t)} **********************************************/

    c0 = clock();
    {
        fmpz_t pN;
        fmpz_poly_t t;

        fmpz_init(pN);
        fmpz_poly_init(t);

        fmpz_pow_ui(pN, p, prec->N2 - vF);

        /* Compute r(t)^m mod p^{N2-vF} */
        if (prec->denR == NULL)
        {
            fmpz_mod_poly_t _t;

            fmpz_mod_poly_init(_t, pN);
            fmpz_mod_poly_set_fmpz_poly(_t, r);
            fmpz_mod_poly_pow(_t, _t, prec->m);
            fmpz_mod_poly_get_fmpz_poly(t, _t);
            fmpz_mod_poly_clear(_t);
        }
        else
        {
            /* TODO: We don't really need a copy */
            fmpz_poly_set(t, prec->denR);
        }

        fmpz_poly_mat_scalar_mul_fmpz_poly(F, F, t);
        fmpz_poly_mat_scalar_mod_fmpz(F, F, pN);

        /* TODO: This should not be necessary? */
        fmpz_poly_mat_truncate(F, prec->K);

        fmpz_clear(pN);
        fmpz_poly_clear(t);
    }
    c1 = clock();
    c  = (double) (c1 - c0) / CLOCKS_PER_SEC;
    if (verbose)
    {
        printf("Analytic continuation:\n");
        printf("  Time = %f\n", c);
        printf("\n");
        fflush(stdout);
    }

    /* Steps 6 and 7 *********************************************************/

    if (a == 1)
    {
        /* Step 6 {F(1) = r(t_1)^{-m} G(t_1)} ********************************/

        c0 = clock();
        {
            const long N = prec->N2 - vF;

            fmpz_t f, g, t, pN;

            fmpz_init(f);
            fmpz_init(g);
            fmpz_init(t);
            fmpz_init(pN);

            fmpz_pow_ui(pN, p, N);

            /* f := \hat{t_1}, g := r(\hat{t_1})^{-m} */
            _padic_teichmuller(f, t1->coeffs + 0, p, N);
            if (prec->denR == NULL)
            {
                _fmpz_mod_poly_evaluate_fmpz(g, r->coeffs, r->length, f, pN);
                fmpz_powm_ui(t, g, prec->m, pN);
            }
            else
            {
                _fmpz_mod_poly_evaluate_fmpz(t, prec->denR->coeffs, prec->denR->length, f, pN);
            }
            _padic_inv(g, t, p, N);

            /* F1 := g G(\hat{t_1}) */
            for (i = 0; i < b; i++)
                for (j = 0; j < b; j++)
                {
                    const fmpz_poly_struct *poly = fmpz_poly_mat_entry(F, i, j);
                    const long len               = poly->length;

                    if (len == 0)
                    {
                        fmpz_poly_zero(fmpz_poly_mat_entry(F1, i, j));
                    }
                    else
                    {
                        fmpz_poly_fit_length(fmpz_poly_mat_entry(F1, i, j), 1);

                        _fmpz_mod_poly_evaluate_fmpz(t, poly->coeffs, len, f, pN);
                        fmpz_mul(fmpz_poly_mat_entry(F1, i, j)->coeffs + 0, g, t);
                        fmpz_mod(fmpz_poly_mat_entry(F1, i, j)->coeffs + 0,
                                 fmpz_poly_mat_entry(F1, i, j)->coeffs + 0, pN);

                        _fmpz_poly_set_length(fmpz_poly_mat_entry(F1, i, j), 1);
                        _fmpz_poly_normalise(fmpz_poly_mat_entry(F1, i, j));
                    }
                }

            vF1 = vF;
            fmpz_poly_mat_canonicalise(F1, &vF1, p);

            fmpz_clear(f);
            fmpz_clear(g);
            fmpz_clear(t);
            fmpz_clear(pN);
        }
        c1 = clock();
        c  = (double) (c1 - c0) / CLOCKS_PER_SEC;
        if (verbose)
        {
            printf("Evaluation:\n");
            printf("  Time = %f\n", c);
            printf("\n");
            fflush(stdout);
        }
    }
    else
    {
        /* Step 6 {F(1) = r(t_1)^{-m} G(t_1)} ********************************/

        c0 = clock();
        {
            const long N = prec->N2 - vF;
            fmpz_t pN;
            fmpz *f, *g, *t;

            fmpz_init(pN);

            f = _fmpz_vec_init(a);
            g = _fmpz_vec_init(2 * a - 1);
            t = _fmpz_vec_init(2 * a - 1);

            fmpz_pow_ui(pN, p, N);

            /* f := \hat{t_1}, g := r(\hat{t_1})^{-m} */
            _qadic_teichmuller(f, t1->coeffs, t1->length, Qq->a, Qq->j, Qq->len, p, N);
            if (prec->denR == NULL)
            {
                fmpz_t e;
                fmpz_init_set_ui(e, prec->m);
                _fmpz_mod_poly_compose_smod(g, r->coeffs, r->length, f, a,
                                            Qq->a, Qq->j, Qq->len, pN);
                _qadic_pow(t, g, a, e, Qq->a, Qq->j, Qq->len, pN);
                fmpz_clear(e);
            }
            else
            {
                _fmpz_mod_poly_reduce(prec->denR->coeffs, prec->denR->length, Qq->a, Qq->j, Qq->len, pN);
                _fmpz_poly_normalise(prec->denR);

                _fmpz_mod_poly_compose_smod(t, prec->denR->coeffs, prec->denR->length, f, a,
                                            Qq->a, Qq->j, Qq->len, pN);
            }
            _qadic_inv(g, t, a, Qq->a, Qq->j, Qq->len, p, N);

            /* F1 := g G(\hat{t_1}) */
            for (i = 0; i < b; i++)
                for (j = 0; j < b; j++)
                {
                    const fmpz_poly_struct *poly = fmpz_poly_mat_entry(F, i, j);
                    const long len               = poly->length;

                    fmpz_poly_struct *poly2 = fmpz_poly_mat_entry(F1, i, j);

                    if (len == 0)
                    {
                        fmpz_poly_zero(poly2);
                    }
                    else
                    {
                        _fmpz_mod_poly_compose_smod(t, poly->coeffs, len, f, a,
                                                    Qq->a, Qq->j, Qq->len, pN);

                        fmpz_poly_fit_length(poly2, 2 * a - 1);
                        _fmpz_poly_mul(poly2->coeffs, g, a, t, a);
                        _fmpz_mod_poly_reduce(poly2->coeffs, 2 * a - 1, Qq->a, Qq->j, Qq->len, pN);
                        _fmpz_poly_set_length(poly2, a);
                        _fmpz_poly_normalise(poly2);
                    }
                }

            /* Now the matrix for p^{-1} F_p at t=t_1 is (F1, vF1). */
            vF1 = vF;
            fmpz_poly_mat_canonicalise(F1, &vF1, p);

            fmpz_clear(pN);
            _fmpz_vec_clear(f, a);
            _fmpz_vec_clear(g, 2 * a - 1);
            _fmpz_vec_clear(t, 2 * a - 1);
        }
        c1 = clock();
        c  = (double) (c1 - c0) / CLOCKS_PER_SEC;
        if (verbose)
        {
            printf("Evaluation:\n");
            printf("  Time = %f\n", c);
            printf("\n");
            fflush(stdout);
        }

        /* Step 7 {Norm} *****************************************************/
        /*
            Computes the matrix for $q^{-1} F_q$ at $t = t_1$ as the
            product $F \sigma(F) \dotsm \sigma^{a-1}(F)$ up appropriate
            transpositions because our convention of columns vs rows is
            the opposite of that used by Gerkmann.

            Note that, in any case, transpositions do not affect
            the characteristic polynomial.
         */

        c0 = clock();
        {
            const long N = prec->N1 - a * vF1;

            fmpz_t pN;
            fmpz_poly_mat_t T;

            fmpz_init(pN);
            fmpz_poly_mat_init(T, b, b);

            fmpz_pow_ui(pN, p, N);

            fmpz_poly_mat_frobenius(T, F1, 1, p, N, Qq);
            _qadic_mat_mul(F1, F1, T, pN, Qq);

            for (i = 2; i < a; i++)
            {
                fmpz_poly_mat_frobenius(T, T, 1, p, N, Qq);
                _qadic_mat_mul(F1, F1, T, pN, Qq);
            }

            vF1 = a * vF1;
            fmpz_poly_mat_canonicalise(F1, &vF1, p);

            fmpz_clear(pN);
            fmpz_poly_mat_clear(T);
        }
        c1 = clock();
        c  = (double) (c1 - c0) / CLOCKS_PER_SEC;
        if (verbose)
        {
            printf("Norm:\n");
            printf("  Time = %f\n", c);
            printf("\n");
            fflush(stdout);
        }
    }

    /* Step 8 {Reverse characteristic polynomial} ****************************/

    c0 = clock();

    deformation_revcharpoly(cp, F1, vF1, n, d, prec->N0, prec->r, prec->s, Qq);

    c1 = clock();
    c  = (double) (c1 - c0) / CLOCKS_PER_SEC;
    if (verbose)
    {
        printf("Reverse characteristic polynomial:\n");
        printf("  p(T) = "), fmpz_poly_print_pretty(cp, "T"), printf("\n");
        printf("  Time = %f\n", c);
        printf("\n");
        fflush(stdout);
    }

    /* Clean up **************************************************************/

    padic_mat_clear(F0);

    mat_clear(M, ctxFracQt);
    free(bR);
    free(bC);
    fmpz_poly_clear(r);

    fmpz_poly_mat_clear(C);
    fmpz_poly_mat_clear(Cinv);

    fmpz_poly_mat_clear(F);
    fmpz_poly_mat_clear(F1);
    fmpz_poly_clear(cp);
}
Ejemplo n.º 8
0
static void 
_qadic_exp_bsplit_series(fmpz *P, fmpz_t Q, fmpz *T, 
                         const fmpz *x, slong len, slong lo, slong hi, 
                         const fmpz *a, const slong *j, slong lena)
{
    const slong d = j[lena - 1];

    if (hi - lo == 1)
    {
        _fmpz_vec_set(P, x, len);
        _fmpz_vec_zero(P + len, 2*d - 1 - len);

        fmpz_set_si(Q, lo);

        _fmpz_vec_set(T, P, 2*d - 1);
    }
    else if (hi - lo == 2)
    {
        _fmpz_poly_sqr(P, x, len);
        _fmpz_vec_zero(P + (2*len - 1), d - (2*len - 1));
        _fmpz_poly_reduce(P, 2*len - 1, a, j, lena);

        fmpz_set_si(Q, lo);
        fmpz_mul_si(Q, Q, lo + 1);

        _fmpz_vec_scalar_mul_si(T, x, len, lo + 1);
        _fmpz_vec_zero(T + len, d - len);
        _fmpz_vec_add(T, T, P, d);
    }
    else
    {
        const slong m = (lo + hi) / 2;

        fmpz *PR, *TR, *W;
        fmpz_t QR;

        PR = _fmpz_vec_init(2*d - 1);
        TR = _fmpz_vec_init(2*d - 1);
        W  = _fmpz_vec_init(2*d - 1);
        fmpz_init(QR);

        _qadic_exp_bsplit_series(P, Q, T, x, len, lo, m, a, j, lena);

        _qadic_exp_bsplit_series(PR, QR, TR, x, len, m, hi, a, j, lena);

        _fmpz_poly_mul(W, TR, d, P, d);
        _fmpz_poly_reduce(W, 2*d - 1, a, j, lena);

        _fmpz_vec_scalar_mul_fmpz(T, T, d, QR);
        _fmpz_vec_add(T, T, W, d);

        _fmpz_poly_mul(W, P, d, PR, d);
        _fmpz_poly_reduce(W, 2*d - 1, a, j, lena);
        _fmpz_vec_swap(P, W, d);

        fmpz_mul(Q, Q, QR);

        _fmpz_vec_clear(PR, 2*d - 1);
        _fmpz_vec_clear(TR, 2*d - 1);
        _fmpz_vec_clear(W,  2*d - 1);
        fmpz_clear(QR);
    }
}
Ejemplo n.º 9
0
void _fmpz_mod_poly_mul(fmpz *res, const fmpz *poly1, slong len1, 
                                   const fmpz *poly2, slong len2, const fmpz_t p)
{
    _fmpz_poly_mul(res, poly1, len1, poly2, len2);
    _fmpz_vec_scalar_mod_fmpz(res, res, len1 + len2 - 1, p);
}
Ejemplo n.º 10
0
Archivo: t-mul.c Proyecto: goens/flint2
int
main(void)
{
    int i, result;
    flint_rand_t state;

    printf("mul....");
    fflush(stdout);

    flint_randinit(state);

    /* Check aliasing of a and b */
    for (i = 0; i < 2000; i++)
    {
        fmpz_poly_t a, b, c;

        fmpz_poly_init(a);
        fmpz_poly_init(b);
        fmpz_poly_init(c);
        fmpz_poly_randtest(b, state, n_randint(state, 50), 500);
        fmpz_poly_randtest(c, state, n_randint(state, 50), 500);

        fmpz_poly_mul(a, b, c);
        fmpz_poly_mul(b, b, c);

        result = (fmpz_poly_equal(a, b));
        if (!result)
        {
            printf("FAIL:\n");
            fmpz_poly_print(a), printf("\n\n");
            fmpz_poly_print(b), printf("\n\n");
            abort();
        }

        fmpz_poly_clear(a);
        fmpz_poly_clear(b);
        fmpz_poly_clear(c);
    }

    /* Check aliasing of a and c */
    for (i = 0; i < 2000; i++)
    {
        fmpz_poly_t a, b, c;

        fmpz_poly_init(a);
        fmpz_poly_init(b);
        fmpz_poly_init(c);
        fmpz_poly_randtest(b, state, n_randint(state, 50), 500);
        fmpz_poly_randtest(c, state, n_randint(state, 50), 500);

        fmpz_poly_mul(a, b, c);
        fmpz_poly_mul(c, b, c);

        result = (fmpz_poly_equal(a, c));
        if (!result)
        {
            printf("FAIL:\n");
            fmpz_poly_print(a), printf("\n\n");
            fmpz_poly_print(c), printf("\n\n");
            abort();
        }

        fmpz_poly_clear(a);
        fmpz_poly_clear(b);
        fmpz_poly_clear(c);
    }

    /* Check (b*c)+(b*d) = b*(c+d) */
    for (i = 0; i < 2000; i++)
    {
        fmpz_poly_t a1, a2, b, c, d;

        fmpz_poly_init(a1);
        fmpz_poly_init(a2);
        fmpz_poly_init(b);
        fmpz_poly_init(c);
        fmpz_poly_init(d);
        fmpz_poly_randtest(b, state, n_randint(state, 100), 500);
        fmpz_poly_randtest(c, state, n_randint(state, 100), 500);
        fmpz_poly_randtest(d, state, n_randint(state, 100), 500);

        fmpz_poly_mul(a1, b, c);
        fmpz_poly_mul(a2, b, d);
        fmpz_poly_add(a1, a1, a2);

        fmpz_poly_add(c, c, d);
        fmpz_poly_mul(a2, b, c);

        result = (fmpz_poly_equal(a1, a2));
        if (!result)
        {
            printf("FAIL:\n");
            fmpz_poly_print(a1), printf("\n\n");
            fmpz_poly_print(a2), printf("\n\n");
            abort();
        }

        fmpz_poly_clear(a1);
        fmpz_poly_clear(a2);
        fmpz_poly_clear(b);
        fmpz_poly_clear(c);
        fmpz_poly_clear(d);
    }

    /* Check _fmpz_poly_mul directly */
    for (i = 0; i < 2000; i++)
    {
        long len1, len2;
        fmpz_poly_t a, b, out1, out2;

        len1 = n_randint(state, 100) + 1;
        len2 = n_randint(state, 100) + 1;
        fmpz_poly_init(a);
        fmpz_poly_init(b);
        fmpz_poly_init(out1);
        fmpz_poly_init(out2);
        fmpz_poly_randtest(a, state, len1, 200);
        fmpz_poly_randtest(b, state, len2, 200);

        fmpz_poly_mul(out1, a, b);
        fmpz_poly_fit_length(a, a->alloc + n_randint(state, 10));
        fmpz_poly_fit_length(b, b->alloc + n_randint(state, 10));
        a->length = a->alloc;
        b->length = b->alloc;
        fmpz_poly_fit_length(out2, a->length + b->length - 1);
        if (a->length >= b->length)
            _fmpz_poly_mul(out2->coeffs, a->coeffs, a->length,
                                         b->coeffs, b->length);
        else
            _fmpz_poly_mul(out2->coeffs, b->coeffs, b->length,
                                         a->coeffs, a->length);
        _fmpz_poly_set_length(out2, a->length + b->length - 1);
        _fmpz_poly_normalise(out2);

        result = (fmpz_poly_equal(out1, out2));
        if (!result)
        {
            printf("FAIL:\n");
            fmpz_poly_print(out1), printf("\n\n");
            fmpz_poly_print(out2), printf("\n\n");
            abort();
        }

        fmpz_poly_clear(a);
        fmpz_poly_clear(b);
        fmpz_poly_clear(out1);
        fmpz_poly_clear(out2);
    }

    flint_randclear(state);
    _fmpz_cleanup();
    printf("PASS\n");
    return 0;
}
Ejemplo n.º 11
0
static void 
__fmpz_poly_divrem_divconquer(fmpz * Q, fmpz * R, 
                              const fmpz * A, long lenA, 
                              const fmpz * B, long lenB)
{
    if (lenA < 2 * lenB - 1)
    {
        /*
           Convert unbalanced division into a 2 n1 - 1 by n1 division
         */

        const long n1 = lenA - lenB + 1;
        const long n2 = lenB - n1;

        const fmpz * p1 = A + n2;
        const fmpz * d1 = B + n2;
        const fmpz * d2 = B;

        fmpz * W = _fmpz_vec_init((2 * n1 - 1) + lenB - 1);

        fmpz * d1q1 = R + n2;
        fmpz * d2q1 = W + (2 * n1 - 1);

        _fmpz_poly_divrem_divconquer_recursive(Q, d1q1, W, p1, d1, n1);

        /*
           Compute d2q1 = Q d2, of length lenB - 1
         */

        if (n1 >= n2)
            _fmpz_poly_mul(d2q1, Q, n1, d2, n2);
        else
            _fmpz_poly_mul(d2q1, d2, n2, Q, n1);

        /*
           Compute BQ = d1q1 * x^n1 + d2q1, of length lenB - 1; 
           then compute R = A - BQ
         */

        _fmpz_vec_swap(R, d2q1, n2);
        _fmpz_vec_add(R + n2, R + n2, d2q1 + n2, n1 - 1);
        _fmpz_vec_sub(R, A, R, lenA);

        _fmpz_vec_clear(W, (2 * n1 - 1) + lenB - 1);
    }
    else if (lenA > 2 * lenB - 1)
    {
        /*
           We shift A right until it is of length 2 lenB - 1, call this p1
         */

        const long shift = lenA - 2 * lenB + 1;
        const fmpz * p1 = A + shift;

        fmpz * q1   = Q + shift;
        fmpz * q2   = Q;
        fmpz * W    = R + lenA;
        fmpz * d1q1 = W + (2 * lenB - 1);

        /*
           XXX:  In this case, we expect R to be of length 
           lenA + 2 * (2 * lenB - 1) and A to be modifiable
         */

        /* 
           Set q1 to p1 div B, a 2 lenB - 1 by lenB division, so q1 ends up 
           being of length lenB; set d1q1 = d1 * q1 of length 2 lenB - 1
         */

        _fmpz_poly_divrem_divconquer_recursive(q1, d1q1, W, p1, B, lenB);

        /* 
           We have dq1 = d1 * q1 * x^shift, of length lenA

           Compute R = A - dq1; the first lenB coeffs represent remainder 
           terms (zero if division is exact), leaving lenA - lenB significant 
           terms which we use in the division
         */

        _fmpz_vec_sub((fmpz *) A + shift, A + shift, d1q1, lenB - 1);

        /*
           Compute q2 = trunc(R) div B; it is a smaller division than the 
           original since len(trunc(R)) = lenA - lenB
         */

        __fmpz_poly_divrem_divconquer(q2, R, A, lenA - lenB, B, lenB);

        _fmpz_vec_sub(R + lenA - lenB, A + lenA - lenB, d1q1 + lenB - 1, lenB);

        /*
           We have Q = q1 * x^shift + q2; Q has length lenB + shift; 
           note q2 has length shift since the above division is 
           lenA - lenB by lenB

           We've also written the remainder in place
         */
    }
    else  /* lenA = 2 * lenB - 1 */
    {
        fmpz * W = _fmpz_vec_init(lenA);

        _fmpz_poly_divrem_divconquer_recursive(Q, R, W, A, B, lenB);
        _fmpz_vec_sub(R, A, R, lenA);

        _fmpz_vec_clear(W, lenA);
    }
}