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/* -*- c++ -*- */
/*
* Copyright 2004 Free Software Foundation, Inc.
*
* This file is part of GNU Radio
*
* GNU Radio 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 3, or (at your option)
* any later version.
*
* GNU Radio 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 GNU Radio; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <gr_fxpt.h>
const float gr_fxpt::s_sine_table[1 << NBITS][2] = {
#include "sine_table.h"
};
const float gr_fxpt::PI = 3.14159265358979323846;
const float gr_fxpt::TWO_TO_THE_31 = 2147483648.0;
#if 0
/*
* Compute sine using table lookup with linear interpolation.
* Each table entry contains slope and intercept.
*/
float
gr_fxpt::sin (gr_int32 x)
{
gr_uint32 ux = x;
int index = ux >> (WORDBITS - NBITS);
return s_sine_table[index][0] * (ux >> 1) + s_sine_table[index][1];
}
float
gr_fxpt::cos (gr_int32 x)
{
gr_uint32 ux = x + 0x40000000;
int index = ux >> (WORDBITS - NBITS);
return s_sine_table[index][0] * (ux >> 1) + s_sine_table[index][1];
}
#endif
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