void mag_geom_series(mag_t res, const mag_t x, ulong n) { if (mag_is_zero(x)) { if (n == 0) mag_one(res); else mag_zero(res); } else if (mag_is_inf(x)) { mag_inf(res); } else { mag_t t; mag_init(t); mag_one(t); mag_sub_lower(t, t, x); if (mag_is_zero(t)) { mag_inf(res); } else { mag_pow_ui(res, x, n); mag_div(res, res, t); } mag_clear(t); } }
void mag_exp_tail(mag_t z, const mag_t x, ulong N) { if (N == 0 || mag_is_inf(x)) { mag_exp(z, x); } else if (mag_is_zero(x)) { mag_zero(z); } else { mag_t t; mag_init(t); mag_set_ui_2exp_si(t, N, -1); /* bound by geometric series when N >= 2*x <=> N/2 >= x */ if (mag_cmp(t, x) >= 0) { /* 2 c^N / N! */ mag_pow_ui(t, x, N); mag_rfac_ui(z, N); mag_mul(z, z, t); mag_mul_2exp_si(z, z, 1); } else { mag_exp(z, x); } mag_clear(t); } }
void mag_expinv(mag_t res, const mag_t x) { if (mag_is_zero(x)) { mag_one(res); } else if (mag_is_inf(x)) { mag_zero(res); } else if (fmpz_sgn(MAG_EXPREF(x)) <= 0) { mag_one(res); } else if (fmpz_cmp_ui(MAG_EXPREF(x), 2 * MAG_BITS) > 0) { fmpz_t t; fmpz_init(t); /* If x > 2^60, exp(-x) < 2^(-2^60 / log(2)) */ /* -1/log(2) < -369/256 */ fmpz_set_si(t, -369); fmpz_mul_2exp(t, t, 2 * MAG_BITS - 8); mag_one(res); mag_mul_2exp_fmpz(res, res, t); fmpz_clear(t); } else { fmpz_t t; slong e = MAG_EXP(x); fmpz_init(t); fmpz_set_ui(t, MAG_MAN(x)); if (e >= MAG_BITS) fmpz_mul_2exp(t, t, e - MAG_BITS); else fmpz_tdiv_q_2exp(t, t, MAG_BITS - e); /* upper bound for 1/e */ mag_set_ui_2exp_si(res, 395007543, -30); mag_pow_fmpz(res, res, t); fmpz_clear(t); } }
void acb_pow_arb(acb_t z, const acb_t x, const arb_t y, long prec) { const arf_struct * ymid = arb_midref(y); const mag_struct * yrad = arb_radref(y); if (arb_is_zero(y)) { acb_one(z); return; } if (mag_is_zero(yrad)) { /* small half-integer or integer */ if (arf_cmpabs_2exp_si(ymid, BINEXP_LIMIT) < 0 && arf_is_int_2exp_si(ymid, -1)) { fmpz_t e; fmpz_init(e); if (arf_is_int(ymid)) { arf_get_fmpz_fixed_si(e, ymid, 0); acb_pow_fmpz_binexp(z, x, e, prec); } else { /* hack: give something finite here (should fix sqrt/rsqrt etc) */ if (arb_contains_zero(acb_imagref(x)) && arb_contains_nonpositive(acb_realref(x))) { _acb_pow_arb_exp(z, x, y, prec); fmpz_clear(e); return; } arf_get_fmpz_fixed_si(e, ymid, -1); acb_sqrt(z, x, prec + fmpz_bits(e)); acb_pow_fmpz_binexp(z, z, e, prec); } fmpz_clear(e); return; } } _acb_pow_arb_exp(z, x, y, prec); }
void arb_atan(arb_t z, const arb_t x, slong prec) { if (arb_is_exact(x)) { arb_atan_arf(z, arb_midref(x), prec); } else { mag_t t, u; mag_init(t); mag_init(u); arb_get_mag_lower(t, x); if (mag_is_zero(t)) { mag_set(t, arb_radref(x)); } else { mag_mul_lower(t, t, t); mag_one(u); mag_add_lower(t, t, u); mag_div(t, arb_radref(x), t); } if (mag_cmp_2exp_si(t, 0) > 0) { mag_const_pi(u); mag_min(t, t, u); } arb_atan_arf(z, arb_midref(x), prec); mag_add(arb_radref(z), arb_radref(z), t); mag_clear(t); mag_clear(u); } }
void arb_sqrtpos(arb_t z, const arb_t x, long prec) { if (!arb_is_finite(x)) { if (mag_is_zero(arb_radref(x)) && arf_is_pos_inf(arb_midref(x))) arb_pos_inf(z); else arb_zero_pm_inf(z); } else if (arb_contains_nonpositive(x)) { arf_t t; arf_init(t); arf_set_mag(t, arb_radref(x)); arf_add(t, arb_midref(x), t, MAG_BITS, ARF_RND_CEIL); if (arf_sgn(t) <= 0) { arb_zero(z); } else { arf_sqrt(t, t, MAG_BITS, ARF_RND_CEIL); arf_mul_2exp_si(t, t, -1); arf_set(arb_midref(z), t); arf_get_mag(arb_radref(z), t); } arf_clear(t); } else { arb_sqrt(z, x, prec); } arb_nonnegative_part(z, z, prec); }
double mag_get_d(const mag_t z) { if (mag_is_zero(z)) { return 0.0; } else if (mag_is_inf(z)) { return D_INF; } else if (MAG_EXP(z) < -1000 || MAG_EXP(z) > 1000) { if (fmpz_sgn(MAG_EXPREF(z)) < 0) return ldexp(1.0, -1000); else return D_INF; } else { return ldexp(MAG_MAN(z), MAG_EXP(z) - MAG_BITS); } }
void arb_log(arb_t y, const arb_t x, slong prec) { if (arb_is_exact(x)) { arb_log_arf(y, arb_midref(x), prec); } else { /* Let the input be [a-b, a+b]. We require a > b >= 0 (otherwise the interval contains zero or a negative number and the logarithm is not defined). The error is largest at a-b, and we have log(a) - log(a-b) = log(1 + b/(a-b)). */ mag_t err; mag_init(err); arb_get_mag_lower_nonnegative(err, x); if (mag_is_zero(err)) { mag_inf(err); } else { mag_div(err, arb_radref(x), err); mag_log1p(err, err); } arb_log_arf(y, arb_midref(x), prec); mag_add(arb_radref(y), arb_radref(y), err); mag_clear(err); } }
void _arb_poly_mullow_block(arb_ptr z, arb_srcptr x, slong xlen, arb_srcptr y, slong ylen, slong n, slong prec) { slong xmlen, xrlen, ymlen, yrlen, i; fmpz *xz, *yz, *zz; fmpz *xe, *ye; slong *xblocks, *yblocks; int squaring; fmpz_t scale, t; xlen = FLINT_MIN(xlen, n); ylen = FLINT_MIN(ylen, n); squaring = (x == y) && (xlen == ylen); /* Strip trailing zeros */ xmlen = xrlen = xlen; while (xmlen > 0 && arf_is_zero(arb_midref(x + xmlen - 1))) xmlen--; while (xrlen > 0 && mag_is_zero(arb_radref(x + xrlen - 1))) xrlen--; if (squaring) { ymlen = xmlen; yrlen = xrlen; } else { ymlen = yrlen = ylen; while (ymlen > 0 && arf_is_zero(arb_midref(y + ymlen - 1))) ymlen--; while (yrlen > 0 && mag_is_zero(arb_radref(y + yrlen - 1))) yrlen--; } /* We don't know how to deal with infinities or NaNs */ if (!_arb_vec_is_finite(x, xlen) || (!squaring && !_arb_vec_is_finite(y, ylen))) { _arb_poly_mullow_classical(z, x, xlen, y, ylen, n, prec); return; } xlen = FLINT_MAX(xmlen, xrlen); ylen = FLINT_MAX(ymlen, yrlen); /* Start with the zero polynomial */ _arb_vec_zero(z, n); /* Nothing to do */ if (xlen == 0 || ylen == 0) return; n = FLINT_MIN(n, xlen + ylen - 1); fmpz_init(scale); fmpz_init(t); xz = _fmpz_vec_init(xlen); yz = _fmpz_vec_init(ylen); zz = _fmpz_vec_init(n); xe = _fmpz_vec_init(xlen); ye = _fmpz_vec_init(ylen); xblocks = flint_malloc(sizeof(slong) * (xlen + 1)); yblocks = flint_malloc(sizeof(slong) * (ylen + 1)); _arb_poly_get_scale(scale, x, xlen, y, ylen); /* Error propagation */ /* (xm + xr)*(ym + yr) = (xm*ym) + (xr*ym + xm*yr + xr*yr) = (xm*ym) + (xm*yr + xr*(ym + yr)) */ if (xrlen != 0 || yrlen != 0) { mag_ptr tmp; double *xdbl, *ydbl; tmp = _mag_vec_init(FLINT_MAX(xlen, ylen)); xdbl = flint_malloc(sizeof(double) * xlen); ydbl = flint_malloc(sizeof(double) * ylen); /* (xm + xr)^2 = (xm*ym) + (xr^2 + 2 xm xr) = (xm*ym) + xr*(2 xm + xr) */ if (squaring) { _mag_vec_get_fmpz_2exp_blocks(xz, xdbl, xe, xblocks, scale, x, NULL, xrlen); for (i = 0; i < xlen; i++) { arf_get_mag(tmp + i, arb_midref(x + i)); mag_mul_2exp_si(tmp + i, tmp + i, 1); mag_add(tmp + i, tmp + i, arb_radref(x + i)); } _mag_vec_get_fmpz_2exp_blocks(yz, ydbl, ye, yblocks, scale, NULL, tmp, xlen); _arb_poly_addmullow_rad(z, zz, xz, xdbl, xe, xblocks, xrlen, yz, ydbl, ye, yblocks, xlen, n); } else if (yrlen == 0) { /* xr * |ym| */ _mag_vec_get_fmpz_2exp_blocks(xz, xdbl, xe, xblocks, scale, x, NULL, xrlen); for (i = 0; i < ymlen; i++) arf_get_mag(tmp + i, arb_midref(y + i)); _mag_vec_get_fmpz_2exp_blocks(yz, ydbl, ye, yblocks, scale, NULL, tmp, ymlen); _arb_poly_addmullow_rad(z, zz, xz, xdbl, xe, xblocks, xrlen, yz, ydbl, ye, yblocks, ymlen, n); } else { /* |xm| * yr */ for (i = 0; i < xmlen; i++) arf_get_mag(tmp + i, arb_midref(x + i)); _mag_vec_get_fmpz_2exp_blocks(xz, xdbl, xe, xblocks, scale, NULL, tmp, xmlen); _mag_vec_get_fmpz_2exp_blocks(yz, ydbl, ye, yblocks, scale, y, NULL, yrlen); _arb_poly_addmullow_rad(z, zz, xz, xdbl, xe, xblocks, xmlen, yz, ydbl, ye, yblocks, yrlen, n); /* xr*(|ym| + yr) */ if (xrlen != 0) { _mag_vec_get_fmpz_2exp_blocks(xz, xdbl, xe, xblocks, scale, x, NULL, xrlen); for (i = 0; i < ylen; i++) arb_get_mag(tmp + i, y + i); _mag_vec_get_fmpz_2exp_blocks(yz, ydbl, ye, yblocks, scale, NULL, tmp, ylen); _arb_poly_addmullow_rad(z, zz, xz, xdbl, xe, xblocks, xrlen, yz, ydbl, ye, yblocks, ylen, n); } } _mag_vec_clear(tmp, FLINT_MAX(xlen, ylen)); flint_free(xdbl); flint_free(ydbl); } /* multiply midpoints */ if (xmlen != 0 && ymlen != 0) { _arb_vec_get_fmpz_2exp_blocks(xz, xe, xblocks, scale, x, xmlen, prec); if (squaring) { _arb_poly_addmullow_block(z, zz, xz, xe, xblocks, xmlen, xz, xe, xblocks, xmlen, n, prec, 1); } else { _arb_vec_get_fmpz_2exp_blocks(yz, ye, yblocks, scale, y, ymlen, prec); _arb_poly_addmullow_block(z, zz, xz, xe, xblocks, xmlen, yz, ye, yblocks, ymlen, n, prec, 0); } } /* Unscale. */ if (!fmpz_is_zero(scale)) { fmpz_zero(t); for (i = 0; i < n; i++) { arb_mul_2exp_fmpz(z + i, z + i, t); fmpz_add(t, t, scale); } } _fmpz_vec_clear(xz, xlen); _fmpz_vec_clear(yz, ylen); _fmpz_vec_clear(zz, n); _fmpz_vec_clear(xe, xlen); _fmpz_vec_clear(ye, ylen); flint_free(xblocks); flint_free(yblocks); fmpz_clear(scale); fmpz_clear(t); }
slong hypgeom_bound(mag_t error, int r, slong A, slong B, slong K, const mag_t TK, const mag_t z, slong tol_2exp) { mag_t Tn, t, u, one, tol, num, den; slong n, m; mag_init(Tn); mag_init(t); mag_init(u); mag_init(one); mag_init(tol); mag_init(num); mag_init(den); mag_one(one); mag_set_ui_2exp_si(tol, UWORD(1), -tol_2exp); /* approximate number of needed terms */ n = hypgeom_estimate_terms(z, r, tol_2exp); /* required for 1 + O(1/k) part to be decreasing */ n = FLINT_MAX(n, K + 1); /* required for z^k / (k!)^r to be decreasing */ m = hypgeom_root_bound(z, r); n = FLINT_MAX(n, m); /* We now have |R(k)| <= G(k) where G(k) is monotonically decreasing, and can bound the tail using a geometric series as soon as soon as G(k) < 1. */ /* bound T(n-1) */ hypgeom_term_bound(Tn, TK, K, A, B, r, z, n-1); while (1) { /* bound R(n) */ mag_mul_ui(num, z, n); mag_mul_ui(num, num, n - B); mag_set_ui_lower(den, n - A); mag_mul_ui_lower(den, den, n - 2*B); if (r != 0) { mag_set_ui_lower(u, n); mag_pow_ui_lower(u, u, r); mag_mul_lower(den, den, u); } mag_div(t, num, den); /* multiply bound for T(n-1) by bound for R(n) to bound T(n) */ mag_mul(Tn, Tn, t); /* geometric series termination check */ /* u = max(1-t, 0), rounding down [lower bound] */ mag_sub_lower(u, one, t); if (!mag_is_zero(u)) { mag_div(u, Tn, u); if (mag_cmp(u, tol) < 0) { mag_set(error, u); break; } } /* move on to next term */ n++; } mag_clear(Tn); mag_clear(t); mag_clear(u); mag_clear(one); mag_clear(tol); mag_clear(num); mag_clear(den); return n; }
void _arb_sin_cos_generic(arb_t s, arb_t c, const arf_t x, const mag_t xrad, slong prec) { int want_sin, want_cos; slong maglim; want_sin = (s != NULL); want_cos = (c != NULL); if (arf_is_zero(x) && mag_is_zero(xrad)) { if (want_sin) arb_zero(s); if (want_cos) arb_one(c); return; } if (!arf_is_finite(x) || !mag_is_finite(xrad)) { if (arf_is_nan(x)) { if (want_sin) arb_indeterminate(s); if (want_cos) arb_indeterminate(c); } else { if (want_sin) arb_zero_pm_one(s); if (want_cos) arb_zero_pm_one(c); } return; } maglim = FLINT_MAX(65536, 4 * prec); if (mag_cmp_2exp_si(xrad, -16) > 0 || arf_cmpabs_2exp_si(x, maglim) > 0) { _arb_sin_cos_wide(s, c, x, xrad, prec); return; } if (arf_cmpabs_2exp_si(x, -(prec/2) - 2) <= 0) { mag_t t, u, v; mag_init(t); mag_init(u); mag_init(v); arf_get_mag(t, x); mag_add(t, t, xrad); mag_mul(u, t, t); /* |sin(z)-z| <= z^3/6 */ if (want_sin) { arf_set(arb_midref(s), x); mag_set(arb_radref(s), xrad); arb_set_round(s, s, prec); mag_mul(v, u, t); mag_div_ui(v, v, 6); arb_add_error_mag(s, v); } /* |cos(z)-1| <= z^2/2 */ if (want_cos) { arf_one(arb_midref(c)); mag_mul_2exp_si(arb_radref(c), u, -1); } mag_clear(t); mag_clear(u); mag_clear(v); return; } if (mag_is_zero(xrad)) { arb_sin_cos_arf_generic(s, c, x, prec); } else { mag_t t; slong exp, radexp; mag_init_set(t, xrad); exp = arf_abs_bound_lt_2exp_si(x); radexp = MAG_EXP(xrad); if (radexp < MAG_MIN_LAGOM_EXP || radexp > MAG_MAX_LAGOM_EXP) radexp = MAG_MIN_LAGOM_EXP; if (want_cos && exp < -2) prec = FLINT_MIN(prec, 20 - FLINT_MAX(exp, radexp) - radexp); else prec = FLINT_MIN(prec, 20 - radexp); arb_sin_cos_arf_generic(s, c, x, prec); /* todo: could use quadratic bound */ if (want_sin) mag_add(arb_radref(s), arb_radref(s), t); if (want_cos) mag_add(arb_radref(c), arb_radref(c), t); mag_clear(t); } }
void arb_mat_exp(arb_mat_t B, const arb_mat_t A, slong prec) { slong i, j, dim, wp, N, q, r; mag_t norm, err; arb_mat_t T; dim = arb_mat_nrows(A); if (dim != arb_mat_ncols(A)) { flint_printf("arb_mat_exp: a square matrix is required!\n"); abort(); } if (dim == 0) { return; } else if (dim == 1) { arb_exp(arb_mat_entry(B, 0, 0), arb_mat_entry(A, 0, 0), prec); return; } wp = prec + 3 * FLINT_BIT_COUNT(prec); mag_init(norm); mag_init(err); arb_mat_init(T, dim, dim); arb_mat_bound_inf_norm(norm, A); if (mag_is_zero(norm)) { arb_mat_one(B); } else { q = pow(wp, 0.25); /* wanted magnitude */ if (mag_cmp_2exp_si(norm, 2 * wp) > 0) /* too big */ r = 2 * wp; else if (mag_cmp_2exp_si(norm, -q) < 0) /* tiny, no need to reduce */ r = 0; else r = FLINT_MAX(0, q + MAG_EXP(norm)); /* reduce to magnitude 2^(-r) */ arb_mat_scalar_mul_2exp_si(T, A, -r); mag_mul_2exp_si(norm, norm, -r); N = _arb_mat_exp_choose_N(norm, wp); mag_exp_tail(err, norm, N); _arb_mat_exp_taylor(B, T, N, wp); for (i = 0; i < dim; i++) for (j = 0; j < dim; j++) arb_add_error_mag(arb_mat_entry(B, i, j), err); for (i = 0; i < r; i++) { arb_mat_mul(T, B, B, wp); arb_mat_swap(T, B); } for (i = 0; i < dim; i++) for (j = 0; j < dim; j++) arb_set_round(arb_mat_entry(B, i, j), arb_mat_entry(B, i, j), prec); } mag_clear(norm); mag_clear(err); arb_mat_clear(T); }
void acb_inv(acb_t res, const acb_t z, slong prec) { mag_t am, bm; slong hprec; #define a arb_midref(acb_realref(z)) #define b arb_midref(acb_imagref(z)) #define x arb_radref(acb_realref(z)) #define y arb_radref(acb_imagref(z)) /* choose precision for the floating-point approximation of a^2+b^2 so that the double rounding result in less than 2 ulp error; also use at least MAG_BITS bits since the value will be recycled for error bounds */ hprec = FLINT_MAX(prec + 3, MAG_BITS); if (arb_is_zero(acb_imagref(z))) { arb_inv(acb_realref(res), acb_realref(z), prec); arb_zero(acb_imagref(res)); return; } if (arb_is_zero(acb_realref(z))) { arb_inv(acb_imagref(res), acb_imagref(z), prec); arb_neg(acb_imagref(res), acb_imagref(res)); arb_zero(acb_realref(res)); return; } if (!acb_is_finite(z)) { acb_indeterminate(res); return; } if (mag_is_zero(x) && mag_is_zero(y)) { int inexact; arf_t a2b2; arf_init(a2b2); inexact = arf_sosq(a2b2, a, b, hprec, ARF_RND_DOWN); if (arf_is_special(a2b2)) { acb_indeterminate(res); } else { _arb_arf_div_rounded_den(acb_realref(res), a, a2b2, inexact, prec); _arb_arf_div_rounded_den(acb_imagref(res), b, a2b2, inexact, prec); arf_neg(arb_midref(acb_imagref(res)), arb_midref(acb_imagref(res))); } arf_clear(a2b2); return; } mag_init(am); mag_init(bm); /* first bound |a|-x, |b|-y */ arb_get_mag_lower(am, acb_realref(z)); arb_get_mag_lower(bm, acb_imagref(z)); if ((mag_is_zero(am) && mag_is_zero(bm))) { acb_indeterminate(res); } else { /* The propagated error in the real part is given exactly by (a+x')/((a+x')^2+(b+y'))^2 - a/(a^2+b^2) = P / Q, P = [(b^2-a^2) x' - a (x'^2+y'^2 + 2y'b)] Q = [(a^2+b^2)((a+x')^2+(b+y')^2)] where |x'| <= x and |y'| <= y, and analogously for the imaginary part. */ mag_t t, u, v, w; arf_t a2b2; int inexact; mag_init(t); mag_init(u); mag_init(v); mag_init(w); arf_init(a2b2); inexact = arf_sosq(a2b2, a, b, hprec, ARF_RND_DOWN); /* compute denominator */ /* t = (|a|-x)^2 + (|b|-x)^2 (lower bound) */ mag_mul_lower(t, am, am); mag_mul_lower(u, bm, bm); mag_add_lower(t, t, u); /* u = a^2 + b^2 (lower bound) */ arf_get_mag_lower(u, a2b2); /* t = ((|a|-x)^2 + (|b|-x)^2)(a^2 + b^2) (lower bound) */ mag_mul_lower(t, t, u); /* compute numerator */ /* real: |a^2-b^2| x + |a| ((x^2 + y^2) + 2 |b| y)) */ /* imag: |a^2-b^2| y + |b| ((x^2 + y^2) + 2 |a| x)) */ /* am, bm = upper bounds for a, b */ arf_get_mag(am, a); arf_get_mag(bm, b); /* v = x^2 + y^2 */ mag_mul(v, x, x); mag_addmul(v, y, y); /* u = |a| ((x^2 + y^2) + 2 |b| y) */ mag_mul_2exp_si(u, bm, 1); mag_mul(u, u, y); mag_add(u, u, v); mag_mul(u, u, am); /* v = |b| ((x^2 + y^2) + 2 |a| x) */ mag_mul_2exp_si(w, am, 1); mag_addmul(v, w, x); mag_mul(v, v, bm); /* w = |b^2 - a^2| (upper bound) */ if (arf_cmpabs(a, b) >= 0) mag_mul(w, am, am); else mag_mul(w, bm, bm); mag_addmul(u, w, x); mag_addmul(v, w, y); mag_div(arb_radref(acb_realref(res)), u, t); mag_div(arb_radref(acb_imagref(res)), v, t); _arb_arf_div_rounded_den_add_err(acb_realref(res), a, a2b2, inexact, prec); _arb_arf_div_rounded_den_add_err(acb_imagref(res), b, a2b2, inexact, prec); arf_neg(arb_midref(acb_imagref(res)), arb_midref(acb_imagref(res))); mag_clear(t); mag_clear(u); mag_clear(v); mag_clear(w); arf_clear(a2b2); } mag_clear(am); mag_clear(bm); #undef a #undef b #undef x #undef y }
void mag_log1p(mag_t z, const mag_t x) { if (mag_is_special(x)) { if (mag_is_zero(x)) mag_zero(z); else mag_inf(z); } else { fmpz exp = MAG_EXP(x); if (!COEFF_IS_MPZ(exp)) { /* Quick bound by x */ if (exp < -10) { mag_set(z, x); return; } else if (exp < 1000) { double t; t = ldexp(MAG_MAN(x), exp - MAG_BITS); t = (1.0 + t) * (1 + 1e-14); t = mag_d_log_upper_bound(t); mag_set_d(z, t); return; } } else if (fmpz_sgn(MAG_EXPREF(x)) < 0) { /* Quick bound by x */ mag_set(z, x); return; } /* Now we must have x >= 2^1000 */ /* Use log(2^(exp-1) * (2*v)) = exp*log(2) + log(2*v) */ { double t; fmpz_t b; mag_t u; mag_init(u); fmpz_init(b); /* incrementing the mantissa gives an upper bound for x+1 */ t = ldexp(MAG_MAN(x) + 1, 1 - MAG_BITS); t = mag_d_log_upper_bound(t); mag_set_d(u, t); /* log(2) < 744261118/2^30 */ _fmpz_add_fast(b, MAG_EXPREF(x), -1); fmpz_mul_ui(b, b, 744261118); mag_set_fmpz(z, b); _fmpz_add_fast(MAG_EXPREF(z), MAG_EXPREF(z), -30); mag_add(z, z, u); mag_clear(u); fmpz_clear(b); } } }