void
nmod_poly_compose_series_horner(nmod_poly_t res,
const nmod_poly_t poly1, const nmod_poly_t poly2, long n)
{
long len1 = poly1->length;
long len2 = poly2->length;
long lenr;
if (len2 != 0 && poly2->coeffs[0] != 0)
{
printf("exception: nmod_poly_compose_series_horner: inner polynomial "
"must have zero constant term\n");
abort();
}
if (len1 == 0 || n == 0)
{
nmod_poly_zero(res);
return;
}
if (len2 == 0 || len1 == 1)
{
nmod_poly_fit_length(res, 1);
res->coeffs[0] = poly1->coeffs[0];
res->length = 1;
_nmod_poly_normalise(res);
return;
}
lenr = FLINT_MIN((len1 - 1) * (len2 - 1) + 1, n);
len1 = FLINT_MIN(len1, lenr);
len2 = FLINT_MIN(len2, lenr);
if ((res != poly1) && (res != poly2))
{
nmod_poly_fit_length(res, lenr);
_nmod_poly_compose_series_horner(res->coeffs, poly1->coeffs, len1,
poly2->coeffs, len2, lenr, res->mod);
res->length = lenr;
_nmod_poly_normalise(res);
}
else
{
nmod_poly_t t;
nmod_poly_init2_preinv(t, res->mod.n, res->mod.ninv, lenr);
_nmod_poly_compose_series_horner(t->coeffs, poly1->coeffs, len1,
poly2->coeffs, len2, lenr, res->mod);
t->length = lenr;
_nmod_poly_normalise(t);
nmod_poly_swap(res, t);
nmod_poly_clear(t);
}
}
void
nmod_poly_div_basecase(nmod_poly_t Q, const nmod_poly_t A,
const nmod_poly_t B)
{
mp_ptr Q_coeffs, W;
nmod_poly_t t1;
long Alen, Blen;
Blen = B->length;
if (Blen == 0)
{
printf("Exception: division by zero in nmod_poly_div_basecase\n");
abort();
}
Alen = A->length;
if (Alen < Blen)
{
nmod_poly_zero(Q);
return;
}
if (Q == A || Q == B)
{
nmod_poly_init2_preinv(t1, B->mod.n, B->mod.ninv,
Alen - Blen + 1);
Q_coeffs = t1->coeffs;
}
else
{
nmod_poly_fit_length(Q, Alen - Blen + 1);
Q_coeffs = Q->coeffs;
}
W = _nmod_vec_init(NMOD_DIV_BC_ITCH(Alen, Blen, A->mod));
_nmod_poly_div_basecase(Q_coeffs, W, A->coeffs, Alen,
B->coeffs, Blen, B->mod);
if (Q == A || Q == B)
{
nmod_poly_swap(Q, t1);
nmod_poly_clear(t1);
}
Q->length = Alen - Blen + 1;
_nmod_vec_clear(W);
_nmod_poly_normalise(Q);
}
void
nmod_poly_mullow_classical(nmod_poly_t res,
const nmod_poly_t poly1, const nmod_poly_t poly2,
slong trunc)
{
slong len_out;
if (poly1->length == 0 || poly2->length == 0 || trunc == 0)
{
nmod_poly_zero(res);
return;
}
len_out = poly1->length + poly2->length - 1;
if (trunc > len_out)
trunc = len_out;
if (res == poly1 || res == poly2)
{
nmod_poly_t temp;
nmod_poly_init2_preinv(temp, poly1->mod.n, poly1->mod.ninv, trunc);
if (poly1->length >= poly2->length)
_nmod_poly_mullow_classical(temp->coeffs, poly1->coeffs,
poly1->length, poly2->coeffs,
poly2->length, trunc, poly1->mod);
else
_nmod_poly_mullow_classical(temp->coeffs, poly2->coeffs,
poly2->length, poly1->coeffs,
poly1->length, trunc, poly1->mod);
nmod_poly_swap(res, temp);
nmod_poly_clear(temp);
}
else
{
nmod_poly_fit_length(res, trunc);
if (poly1->length >= poly2->length)
_nmod_poly_mullow_classical(res->coeffs, poly1->coeffs,
poly1->length, poly2->coeffs,
poly2->length, trunc, poly1->mod);
else
_nmod_poly_mullow_classical(res->coeffs, poly2->coeffs,
poly2->length, poly1->coeffs,
poly1->length, trunc, poly1->mod);
}
res->length = trunc;
_nmod_poly_normalise(res);
}
void
nmod_poly_mullow_KS(nmod_poly_t res,
const nmod_poly_t poly1, const nmod_poly_t poly2,
mp_bitcnt_t bits, long n)
{
long len_out;
if ((poly1->length == 0) || (poly2->length == 0))
{
nmod_poly_zero(res);
return;
}
len_out = poly1->length + poly2->length - 1;
if (n > len_out)
n = len_out;
if (res == poly1 || res == poly2)
{
nmod_poly_t temp;
nmod_poly_init2_preinv(temp, poly1->mod.n, poly1->mod.ninv, len_out);
if (poly1->length >= poly2->length)
_nmod_poly_mullow_KS(temp->coeffs, poly1->coeffs, poly1->length,
poly2->coeffs, poly2->length, bits,
n, poly1->mod);
else
_nmod_poly_mullow_KS(temp->coeffs, poly2->coeffs, poly2->length,
poly1->coeffs, poly1->length, bits,
n, poly1->mod);
nmod_poly_swap(res, temp);
nmod_poly_clear(temp);
}
else
{
nmod_poly_fit_length(res, len_out);
if (poly1->length >= poly2->length)
_nmod_poly_mullow_KS(res->coeffs, poly1->coeffs, poly1->length,
poly2->coeffs, poly2->length, bits,
n, poly1->mod);
else
_nmod_poly_mullow_KS(res->coeffs, poly2->coeffs, poly2->length,
poly1->coeffs, poly1->length, bits,
n, poly1->mod);
}
res->length = n;
_nmod_poly_normalise(res);
}
void
nmod_poly_rem_basecase(nmod_poly_t R, const nmod_poly_t A, const nmod_poly_t B)
{
const long lenA = A->length, lenB = B->length;
mp_ptr r, W;
nmod_poly_t t;
if (lenB == 0)
{
printf("Exception: division by zero in nmod_poly_rem_basecase\n");
abort();
}
if (lenA < lenB)
{
nmod_poly_set(R, A);
return;
}
if (R == A || R == B)
{
nmod_poly_init2_preinv(t, B->mod.n, B->mod.ninv, lenB - 1);
r = t->coeffs;
}
else
{
nmod_poly_fit_length(R, lenB - 1);
r = R->coeffs;
}
W = _nmod_vec_init(NMOD_DIVREM_BC_ITCH(lenA, lenB, A->mod));
_nmod_poly_rem_basecase(r, W, A->coeffs, lenA,
B->coeffs, lenB, B->mod);
if (R == A || R == B)
{
nmod_poly_swap(R, t);
nmod_poly_clear(t);
}
R->length = lenB - 1;
_nmod_vec_clear(W);
_nmod_poly_normalise(R);
}
void
nmod_poly_divrem_basecase(nmod_poly_t Q, nmod_poly_t R, const nmod_poly_t A,
const nmod_poly_t B)
{
const slong lenA = A->length, lenB = B->length;
mp_ptr Q_coeffs, R_coeffs, W;
nmod_poly_t t1, t2;
TMP_INIT;
if (lenB == 0)
{
flint_printf("Exception (nmod_poly_divrem). Division by zero.\n");
abort();
}
if (lenA < lenB)
{
nmod_poly_set(R, A);
nmod_poly_zero(Q);
return;
}
if (Q == A || Q == B)
{
nmod_poly_init2_preinv(t1, B->mod.n, B->mod.ninv, lenA - lenB + 1);
Q_coeffs = t1->coeffs;
}
else
{
nmod_poly_fit_length(Q, lenA - lenB + 1);
Q_coeffs = Q->coeffs;
}
if (R == A || R == B)
{
nmod_poly_init2_preinv(t2, B->mod.n, B->mod.ninv, lenB - 1);
R_coeffs = t2->coeffs;
}
else
{
nmod_poly_fit_length(R, lenB - 1);
R_coeffs = R->coeffs;
}
TMP_START;
W = TMP_ALLOC(NMOD_DIVREM_BC_ITCH(lenA, lenB, A->mod)*sizeof(mp_limb_t));
_nmod_poly_divrem_basecase(Q_coeffs, R_coeffs, W, A->coeffs, lenA,
B->coeffs, lenB, B->mod);
if (Q == A || Q == B)
{
nmod_poly_swap(Q, t1);
nmod_poly_clear(t1);
}
if (R == A || R == B)
{
nmod_poly_swap(R, t2);
nmod_poly_clear(t2);
}
Q->length = lenA - lenB + 1;
R->length = lenB - 1;
TMP_END;
_nmod_poly_normalise(R);
}
void
nmod_poly_init2(nmod_poly_t poly, mp_limb_t n, long alloc)
{
nmod_poly_init2_preinv(poly, n, n_preinvert_limb(n), alloc);
}
