int
arf_add_naive(arf_t z, const arf_t x, const arf_t y, slong prec, arf_rnd_t rnd)
{
if (rnd == ARF_RND_NEAR)
{
arf_add(z, x, y, ARF_PREC_EXACT, ARF_RND_DOWN);
return arf_set_round(z, z, prec, rnd);
}
else
{
fmpr_t a, b;
slong r;
fmpr_init(a);
fmpr_init(b);
arf_get_fmpr(a, x);
arf_get_fmpr(b, y);
r = fmpr_add(a, a, b, prec, rnd);
arf_set_fmpr(z, a);
fmpr_clear(a);
fmpr_clear(b);
return (r == FMPR_RESULT_EXACT) ? 0 : 1;
}
}
int
arf_mul_naive(arf_t z, const arf_t x, const arf_t y, long prec, arf_rnd_t rnd)
{
fmpr_t a, b;
long r;
fmpr_init(a);
fmpr_init(b);
arf_get_fmpr(a, x);
arf_get_fmpr(b, y);
r = fmpr_mul_naive(a, a, b, prec, rnd);
arf_set_fmpr(z, a);
fmpr_clear(a);
fmpr_clear(b);
return (r == FMPR_RESULT_EXACT) ? 0 : 1;
}
void
arf_get_fmpz(fmpz_t z, const arf_t x, arf_rnd_t rnd)
{
if (arf_is_special(x))
{
if (arf_is_zero(x))
{
fmpz_zero(z);
}
else
{
flint_printf("arf_get_fmpz: cannot convert infinity or nan to integer\n");
abort();
}
}
else if (COEFF_IS_MPZ(*ARF_EXPREF(x)))
{
/* tiny */
if (fmpz_sgn(ARF_EXPREF(x)) < 0)
{
int negative = ARF_SGNBIT(x);
if (rnd == ARF_RND_NEAR
|| rnd == ARF_RND_DOWN
|| (rnd == ARF_RND_FLOOR && !negative)
|| (rnd == ARF_RND_CEIL && negative))
{
fmpz_zero(z);
}
else
{
fmpz_set_si(z, negative ? -1 : 1);
}
}
else
{
flint_printf("arf_get_fmpz: number too large to convert to integer\n");
abort();
}
}
else
{
slong exp;
int negative, inexact;
mp_size_t xn, zn;
mp_srcptr xp;
__mpz_struct * zz;
/* TBD: implement efficiently */
if (rnd == ARF_RND_NEAR)
{
fmpr_t t;
fmpr_init(t);
arf_get_fmpr(t, x);
fmpr_get_fmpz(z, t, rnd);
fmpr_clear(t);
return;
}
exp = ARF_EXP(x);
negative = ARF_SGNBIT(x);
/* |x| < 1 */
if (exp <= 0)
{
if (rnd == ARF_RND_DOWN ||
(rnd == ARF_RND_FLOOR && !negative) ||
(rnd == ARF_RND_CEIL && negative))
{
fmpz_zero(z);
}
else
{
fmpz_set_si(z, negative ? -1 : 1);
}
return;
}
ARF_GET_MPN_READONLY(xp, xn, x);
/* |x| < 2^31 or 2^63 (must save 1 bit for rounding up!) */
if (exp < FLINT_BITS)
{
mp_limb_t v, v2;
v = xp[xn - 1];
v2 = v >> (FLINT_BITS - exp);
inexact = (xn > 1) || ((v2 << (FLINT_BITS - exp)) != v);
if (inexact && rnd != ARF_RND_DOWN)
{
if (negative && (rnd == ARF_RND_UP || rnd == ARF_RND_FLOOR))
v2++;
if (!negative && (rnd == ARF_RND_UP || rnd == ARF_RND_CEIL))
v2++;
}
if (negative)
fmpz_neg_ui(z, v2);
else
fmpz_set_ui(z, v2);
return;
}
/* |x| >= 1 */
zn = (exp + FLINT_BITS - 1) / FLINT_BITS;
zz = _fmpz_promote(z);
if (zz->_mp_alloc < zn)
mpz_realloc2(zz, zn * FLINT_BITS);
inexact = _arf_get_integer_mpn(zz->_mp_d, xp, xn, exp);
zz->_mp_size = negative ? -zn : zn;
_fmpz_demote_val(z);
if (inexact && rnd != ARF_RND_DOWN)
{
if (negative && (rnd == ARF_RND_UP || rnd == ARF_RND_FLOOR))
fmpz_sub_ui(z, z, 1);
if (!negative && (rnd == ARF_RND_UP || rnd == ARF_RND_CEIL))
fmpz_add_ui(z, z, 1);
}
}
