Ejemplo n.º 1
0
void
arb_poly_mullow_block(arb_poly_t res, const arb_poly_t poly1,
                      const arb_poly_t poly2, slong n, slong prec)
{
    slong xlen, ylen, zlen;

    xlen = poly1->length;
    ylen = poly2->length;

    if (xlen == 0 || ylen == 0 || n == 0)
    {
        arb_poly_zero(res);
        return;
    }

    xlen = FLINT_MIN(xlen, n);
    ylen = FLINT_MIN(ylen, n);
    zlen = FLINT_MIN(xlen + ylen - 1, n);

    if (res == poly1 || res == poly2)
    {
        arb_poly_t tmp;
        arb_poly_init2(tmp, zlen);
        _arb_poly_mullow_block(tmp->coeffs, poly1->coeffs, xlen,
                               poly2->coeffs, ylen, zlen, prec);
        arb_poly_swap(res, tmp);
        arb_poly_clear(tmp);
    }
    else
    {
        arb_poly_fit_length(res, zlen);
        _arb_poly_mullow_block(res->coeffs, poly1->coeffs, xlen,
                               poly2->coeffs, ylen, zlen, prec);
    }

    _arb_poly_set_length(res, zlen);
    _arb_poly_normalise(res);
}
Ejemplo n.º 2
0
void
_arb_poly_mullow(arb_ptr res,
    arb_srcptr poly1, long len1,
    arb_srcptr poly2, long len2, long n, long prec)
{
    if (n == 1)
    {
        arb_mul(res, poly1, poly2, prec);
    }
    else
    {
        if (n < BLOCK_CUTOFF || len1 < BLOCK_CUTOFF || len2 < BLOCK_CUTOFF)
            _arb_poly_mullow_classical(res, poly1, len1, poly2, len2, n, prec);
        else
            _arb_poly_mullow_block(res, poly1, len1, poly2, len2, n, prec);
    }
}