arb/fmpcb_poly/cos_series.c

/*=============================================================================

    This file is part of ARB.

    ARB is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 of the License, or
    (at your option) any later version.

    ARB is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with ARB; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA

=============================================================================*/
/******************************************************************************

    Copyright (C) 2013 Fredrik Johansson

******************************************************************************/

#include "fmpcb_poly.h"

void
_fmpcb_poly_cos_series(fmpcb_ptr g, fmpcb_srcptr h, long hlen, long n, long prec)
{
    fmpcb_ptr t = _fmpcb_vec_init(n);
    _fmpcb_poly_sin_cos_series(t, g, h, hlen, n, prec);
    _fmpcb_vec_clear(t, n);
}

void
fmpcb_poly_cos_series(fmpcb_poly_t g, const fmpcb_poly_t h, long n, long prec)
{
    if (n == 0)
    {
        fmpcb_poly_zero(g);
        return;
    }

    if (h->length == 0)
    {
        fmpcb_poly_one(g);
        return;
    }

    fmpcb_poly_fit_length(g, n);
    _fmpcb_poly_cos_series(g->coeffs, h->coeffs, h->length, n, prec);
    _fmpcb_poly_set_length(g, n);
    _fmpcb_poly_normalise(g);
}