1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
|
/*=============================================================================
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) 2010 William Hart
******************************************************************************/
#include <gmp.h>
#include "flint.h"
#include "ulong_extras.h"
#include "nmod_poly.h"
void _nmod_poly_derivative(mp_ptr x_prime, mp_srcptr x, slong len, nmod_t mod)
{
slong j;
mp_limb_t k = 1;
for (j = 1; j < len; j++)
{
if (k <= 1)
x_prime[j - 1] = k == 0 ? WORD(0) : x[j];
else
x_prime[j - 1] = n_mulmod2_preinv(x[j], k, mod.n, mod.ninv);
if (++k == mod.n) k = WORD(0);
}
}
void nmod_poly_derivative(nmod_poly_t x_prime, const nmod_poly_t x)
{
if (x->length <= 1)
{
nmod_poly_zero(x_prime);
return;
}
nmod_poly_fit_length(x_prime, x->length - 1);
_nmod_poly_derivative(x_prime->coeffs, x->coeffs, x->length, x->mod);
x_prime->length = x->length - 1;
_nmod_poly_normalise(x_prime);
}
|
