void unif_poly(fmpz_poly_t poly, fmpz_t space, long d) { long i, x; mpz_t randseed; mpz_init(randseed); hcrypt_random(randseed); unsigned long int useed = mpz_get_ui(randseed); srand(useed); for( i = 0 ; i < d ; i++) { x = rand(); fmpz_poly_set_coeff_si(poly, i, x); } fmpz_poly_scalar_smod_fmpz(poly, poly, space); mpz_clear(randseed); }
long _fmpz_poly_hensel_start_lift(fmpz_poly_factor_t lifted_fac, long *link, fmpz_poly_t *v, fmpz_poly_t *w, const fmpz_poly_t f, const nmod_poly_factor_t local_fac, long N) { const long r = local_fac->num; long i, preve; fmpz_t p, P; fmpz_poly_t monic_f; fmpz_init(p); fmpz_init(P); fmpz_poly_init(monic_f); fmpz_set_ui(p, (local_fac->p + 0)->mod.n); fmpz_pow_ui(P, p, N); if (fmpz_is_one(fmpz_poly_lead(f))) { fmpz_poly_set(monic_f, f); } else if (fmpz_cmp_si(fmpz_poly_lead(f), -1) == 0) { fmpz_poly_neg(monic_f, f); } else { fmpz_t t; fmpz_init(t); fmpz_mod(t, fmpz_poly_lead(f), P); if (fmpz_invmod(t, t, P) == 0) { printf("Exception in fmpz_poly_start_hensel_lift.\n"); abort(); } fmpz_poly_scalar_mul_fmpz(monic_f, f, t); fmpz_poly_scalar_mod_fmpz(monic_f, monic_f, P); fmpz_clear(t); } fmpz_poly_hensel_build_tree(link, v, w, local_fac); { long *e, n = FLINT_CLOG2(N) + 1; e = flint_malloc(n * sizeof(long)); for (e[i = 0] = N; e[i] > 1; i++) e[i + 1] = (e[i] + 1) / 2; for (i--; i > 0; i--) { fmpz_poly_hensel_lift_tree(link, v, w, monic_f, r, p, e[i+1], e[i], 1); } if (N > 1) { fmpz_poly_hensel_lift_tree(link, v, w, monic_f, r, p, e[i+1], e[i], 0); } preve = e[i+1]; flint_free(e); } /* Now everything is lifted to p^N, we just need to insert the factors into their correct places in lifted_fac. */ fmpz_poly_factor_fit_length(lifted_fac, r); for (i = 0; i < 2*r - 2; i++) { if (link[i] < 0) { fmpz_poly_scalar_smod_fmpz(lifted_fac->p + (- link[i] - 1), v[i], P); lifted_fac->exp[- link[i] - 1] = 1L; } } lifted_fac->num = r; fmpz_clear(p); fmpz_clear(P); fmpz_poly_clear(monic_f); return preve; }