pqc/external/flint-2.4.3/padic_poly/derivative.c
2014-05-24 23:16:06 +02:00

67 lines
2.1 KiB
C

/*============================================================================
This file is part of FLINT.
FLINT 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.
FLINT 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 FLINT; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
=============================================================================*/
/******************************************************************************
Copyright (C) 2012 Sebastian Pancratz
******************************************************************************/
#include "fmpz_mod_poly.h"
#include "padic_poly.h"
void _padic_poly_derivative(fmpz *rop, slong *rval, slong N,
const fmpz *op, slong val, slong len,
const padic_ctx_t ctx)
{
fmpz_t pow;
int alloc;
_fmpz_poly_derivative(rop, op, len);
*rval = val;
alloc = _padic_ctx_pow_ui(pow, N - *rval, ctx);
_fmpz_vec_scalar_mod_fmpz(rop, rop, len - 1, pow);
_padic_poly_canonicalise(rop, rval, len - 1, ctx->p);
if (alloc)
fmpz_clear(pow);
}
void padic_poly_derivative(padic_poly_t rop,
const padic_poly_t op, const padic_ctx_t ctx)
{
const slong len = op->length;
if (len < 2 || op->val >= rop->N)
{
padic_poly_zero(rop);
}
else
{
padic_poly_fit_length(rop, len - 1);
_padic_poly_derivative(rop->coeffs, &(rop->val), rop->N,
op->coeffs, op->val, len, ctx);
_padic_poly_set_length(rop, len - 1);
_padic_poly_normalise(rop);
}
}