/* Copyright (C) 2002 Jean-Marc Valin */
/**
   @file math_approx.h
   @brief Various math approximation functions for Speex
*/
/*
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   this software without specific prior written permission.
   
   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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*/

#ifndef MATH_APPROX_H
#define MATH_APPROX_H

#include "misc.h"

spx_word16_t spx_cos(spx_word16_t x);
spx_int16_t spx_ilog2(spx_uint32_t x);
spx_int16_t spx_ilog4(spx_uint32_t x);
#ifdef FIXED_POINT
spx_word16_t spx_sqrt(spx_word32_t x);
spx_word16_t spx_acos(spx_word16_t x);
spx_word32_t spx_exp(spx_word16_t x);
spx_word16_t spx_cos_norm(spx_word32_t x);

/* Input in Q15, output in Q14 */
spx_word16_t spx_atan(spx_word32_t x);

#else

#define spx_sqrt sqrt
#define spx_acos acos
#define spx_exp exp
#define spx_cos_norm(x) (cos((.5f*M_PI)*(x)))
#define spx_atan atan

#endif

#endif
