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/** Various utility functions.
*
* Copyright 2008 Marco Cecchetti <mrcekets at gmail.com>
* Copyright 2007 Johan Engelen <goejendaagh@zonnet.nl>
* Copyright 2006 Michael G. Sloan <mgsloan@gmail.com>
*
* This library is free software; you can redistribute it and/or
* modify it either under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation
* (the "LGPL") or, at your option, under the terms of the Mozilla
* Public License Version 1.1 (the "MPL"). If you do not alter this
* notice, a recipient may use your version of this file under either
* the MPL or the LGPL.
*
* You should have received a copy of the LGPL along with this library
* in the file COPYING-LGPL-2.1; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
* You should have received a copy of the MPL along with this library
* in the file COPYING-MPL-1.1
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
* OF ANY KIND, either express or implied. See the LGPL or the MPL for
* the specific language governing rights and limitations.
*
*/
#include <2geom/utils.h>
namespace Geom
{
// return a vector that contains all the binomial coefficients of degree n
void binomial_coefficients(std::vector<size_t>& bc, std::size_t n)
{
size_t s = n+1;
bc.clear();
bc.resize(s);
bc[0] = 1;
for (size_t i = 1; i < n; ++i)
{
size_t k = i >> 1;
if (i & 1u)
{
bc[k+1] = bc[k] << 1;
}
for (size_t j = k; j > 0; --j)
{
bc[j] += bc[j-1];
}
}
s >>= 1;
for (size_t i = 0; i < s; ++i)
{
bc[n-i] = bc[i];
}
}
} // end namespace Geom
/*
Local Variables:
mode:c++
c-file-style:"stroustrup"
c-file-offsets:((innamespace . 0)(inline-open . 0)(case-label . +))
indent-tabs-mode:nil
fill-column:99
End:
*/
// vim: filetype=cpp:expandtab:shiftwidth=4:tabstop=8:softtabstop=4:fileencoding=utf-8:textwidth=99 :
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