arb/arb_poly/binomial_transform.c
2016-04-26 17:20:05 +02:00

49 lines
1.3 KiB
C

/*
Copyright (C) 2013 Fredrik Johansson
This file is part of Arb.
Arb is free software: you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License (LGPL) as published
by the Free Software Foundation; either version 2.1 of the License, or
(at your option) any later version. See <http://www.gnu.org/licenses/>.
*/
#include "arb_poly.h"
void
_arb_poly_binomial_transform(arb_ptr b, arb_srcptr a, slong alen, slong len, slong prec)
{
if (alen < 10 || len < 10)
_arb_poly_binomial_transform_basecase(b, a, alen, len, prec);
else
_arb_poly_binomial_transform_convolution(b, a, alen, len, prec);
}
void
arb_poly_binomial_transform(arb_poly_t b, const arb_poly_t a, slong len, slong prec)
{
if (len == 0 || a->length == 0)
{
arb_poly_zero(b);
return;
}
if (b == a)
{
arb_poly_t c;
arb_poly_init2(c, len);
_arb_poly_binomial_transform(c->coeffs, a->coeffs, a->length, len, prec);
arb_poly_swap(b, c);
arb_poly_clear(c);
}
else
{
arb_poly_fit_length(b, len);
_arb_poly_binomial_transform(b->coeffs, a->coeffs, a->length, len, prec);
}
_arb_poly_set_length(b, len);
_arb_poly_normalise(b);
}