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/*
Copyright (C) 2010 William Hart
Copyright (C) 2011 Fredrik Johansson
Copyright (C) 2013 Mike Hansen
This file is part of FLINT.
FLINT 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 3 of the License, or
(at your option) any later version. See <https://www.gnu.org/licenses/>.
*/
#ifdef T
#include "templates.h"
void
TEMPLATE(T, poly_deflate) (TEMPLATE(T, poly_t) result,
const TEMPLATE(T, poly_t) input, ulong deflation,
const TEMPLATE(T, ctx_t) ctx)
{
slong res_length, i;
if (deflation == 0)
{
flint_throw(FLINT_DIVZERO, "(%s): Division by zero\n", __func__);
}
if (input->length <= 1 || deflation == 1)
{
TEMPLATE(T, poly_set) (result, input, ctx);
return;
}
res_length = (input->length - 1) / deflation + 1;
TEMPLATE(T, poly_fit_length) (result, res_length, ctx);
for (i = 0; i < res_length; i++)
TEMPLATE(T, set) (result->coeffs + i, input->coeffs + (i * deflation),
ctx);
result->length = res_length;
}
#endif