void mag_sqrt(mag_t y, const mag_t x) { if (mag_is_special(x)) { mag_set(y, x); } else { double t; fmpz e; t = MAG_MAN(x) * ldexp(1.0, -MAG_BITS); e = MAG_EXP(x); if (!COEFF_IS_MPZ(e)) { if (e % 2 != 0) { e = (e - 1) >> 1; t *= 2.0; } else { e >>= 1; } t = sqrt(t) * (1 + 1e-13); mag_set_d_2exp_fmpz(y, t, &e); }
static __inline__ void _arb_poly_addmullow_rad(arb_ptr z, fmpz * zz, const fmpz * xz, const double * xdbl, const fmpz * xexps, const slong * xblocks, slong xlen, const fmpz * yz, const double * ydbl, const fmpz * yexps, const slong * yblocks, slong ylen, slong n) { slong i, j, k, ii, xp, yp, xl, yl, bn; fmpz_t zexp; mag_t t; fmpz_init(zexp); mag_init(t); for (i = 0; (xp = xblocks[i]) != xlen; i++) { for (j = 0; (yp = yblocks[j]) != ylen; j++) { if (xp + yp >= n) continue; xl = xblocks[i + 1] - xp; yl = yblocks[j + 1] - yp; bn = FLINT_MIN(xl + yl - 1, n - xp - yp); xl = FLINT_MIN(xl, bn); yl = FLINT_MIN(yl, bn); fmpz_add_inline(zexp, xexps + i, yexps + j); if (xl > 1 && yl > 1 && (xl < DOUBLE_BLOCK_MAX_LENGTH || yl < DOUBLE_BLOCK_MAX_LENGTH)) { fmpz_add_ui(zexp, zexp, 2 * DOUBLE_BLOCK_SHIFT); for (k = 0; k < bn; k++) { /* Classical multiplication (may round down!) */ double ss = 0.0; for (ii = FLINT_MAX(0, k - yl + 1); ii <= FLINT_MIN(xl - 1, k); ii++) { ss += xdbl[xp + ii] * ydbl[yp + k - ii]; } /* Compensate for rounding error */ ss *= DOUBLE_ROUNDING_FACTOR; mag_set_d_2exp_fmpz(t, ss, zexp); mag_add(arb_radref(z + xp + yp + k), arb_radref(z + xp + yp + k), t); } } else { if (xl >= yl) _fmpz_poly_mullow(zz, xz + xp, xl, yz + yp, yl, bn); else _fmpz_poly_mullow(zz, yz + yp, yl, xz + xp, xl, bn); for (k = 0; k < bn; k++) { mag_set_fmpz_2exp_fmpz(t, zz + k, zexp); mag_add(arb_radref(z + xp + yp + k), arb_radref(z + xp + yp + k), t); } } } } fmpz_clear(zexp); mag_clear(t); }
int main() { slong iter; flint_rand_t state; flint_printf("set_d_2exp_fmpz...."); fflush(stdout); flint_randinit(state); for (iter = 0; iter < 100000 * arb_test_multiplier(); iter++) { fmpr_t a, b, c; fmpz_t e; mag_t m; double x; fmpr_init(a); fmpr_init(b); fmpr_init(c); fmpz_init(e); mag_init(m); x = d_randtest2(state); x = ldexp(x, 100 - n_randint(state, 200)); if (n_randint(state, 100) == 0) x = 0.0; fmpz_randtest(e, state, 10); fmpr_set_d(a, x); fmpr_mul_2exp_fmpz(a, a, e); mag_set_d_2exp_fmpz(m, x, e); mag_get_fmpr(b, m); fmpr_set(c, a); fmpr_mul_ui(c, c, 1025, MAG_BITS, FMPR_RND_UP); fmpr_mul_2exp_si(c, c, -10); MAG_CHECK_BITS(m) if (!(fmpr_cmpabs(a, b) <= 0 && fmpr_cmpabs(b, c) <= 0)) { flint_printf("FAIL\n\n"); flint_printf("a = "); fmpr_print(a); flint_printf("\n\n"); flint_printf("b = "); fmpr_print(b); flint_printf("\n\n"); flint_printf("c = "); fmpr_print(c); flint_printf("\n\n"); abort(); } fmpr_clear(a); fmpr_clear(b); fmpr_clear(c); fmpz_clear(e); mag_clear(m); } flint_randclear(state); flint_cleanup(); flint_printf("PASS\n"); return EXIT_SUCCESS; }