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/* ----------------------------------------------------------------------    
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/* ----------------------------------------------------------------------
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* Copyright (C) 2010-2014 ARM Limited. All rights reserved.    
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* Copyright (C) 2010-2014 ARM Limited. All rights reserved.
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*    
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*
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* $Date:        19. March 2015
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* $Date:        21. September 2015
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* $Revision:    V.1.4.5
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* $Revision:    V.1.4.5 a
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*    
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*
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* Project:          CMSIS DSP Library    
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* Project:      CMSIS DSP Library
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* Title:                arm_cos_f32.c    
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* Title:        arm_cos_f32.c
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*    
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*
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* Description:  Fast cosine calculation for floating-point values.  
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* Description:  Fast cosine calculation for floating-point values.
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*    
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*
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* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
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* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
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*  
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*
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* Redistribution and use in source and binary forms, with or without
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* modification, are permitted provided that the following conditions
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* are met:
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* are met:
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*   - Redistributions of source code must retain the above copyright
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*   - Redistributions of source code must retain the above copyright
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*     notice, this list of conditions and the following disclaimer.
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*     notice, this list of conditions and the following disclaimer.
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*   - Redistributions in binary form must reproduce the above copyright
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*   - Redistributions in binary form must reproduce the above copyright
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*     notice, this list of conditions and the following disclaimer in
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*     notice, this list of conditions and the following disclaimer in
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*     the documentation and/or other materials provided with the
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*     the documentation and/or other materials provided with the
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*     distribution.
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*     distribution.
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*   - Neither the name of ARM LIMITED nor the names of its contributors
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*   - Neither the name of ARM LIMITED nor the names of its contributors
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*     may be used to endorse or promote products derived from this
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*     may be used to endorse or promote products derived from this
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*     software without specific prior written permission.
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*     software without specific prior written permission.
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*
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*
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
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* POSSIBILITY OF SUCH DAMAGE.    
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* POSSIBILITY OF SUCH DAMAGE.
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* -------------------------------------------------------------------- */
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* -------------------------------------------------------------------- */
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#include "arm_math.h"
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#include "arm_math.h"
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#include "arm_common_tables.h"
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#include "arm_common_tables.h"
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/**    
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/**
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 * @ingroup groupFastMath    
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 * @ingroup groupFastMath
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 */
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 */
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/**    
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/**
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 * @defgroup cos Cosine    
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 * @defgroup cos Cosine
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 *    
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 *
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 * Computes the trigonometric cosine function using a combination of table lookup  
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 * Computes the trigonometric cosine function using a combination of table lookup
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 * and cubic interpolation.  There are separate functions for  
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 * and linear interpolation.  There are separate functions for
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 * Q15, Q31, and floating-point data types.  
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 * Q15, Q31, and floating-point data types.
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 * The input to the floating-point version is in radians while the  
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 * The input to the floating-point version is in radians while the
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 * fixed-point Q15 and Q31 have a scaled input with the range  
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 * fixed-point Q15 and Q31 have a scaled input with the range
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 * [0 +0.9999] mapping to [0 2*pi).  The fixed-point range is chosen so that a
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 * [0 +0.9999] mapping to [0 2*pi).  The fixed-point range is chosen so that a
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 * value of 2*pi wraps around to 0.
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 * value of 2*pi wraps around to 0.
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 *  
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 *
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 * The implementation is based on table lookup using 256 values together with cubic interpolation.  
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 * The implementation is based on table lookup using 256 values together with linear interpolation.
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 * The steps used are:  
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 * The steps used are:
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 *  -# Calculation of the nearest integer table index  
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 *  -# Calculation of the nearest integer table index
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 *  -# Fetch the four table values a, b, c, and d    
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 *  -# Compute the fractional portion (fract) of the table index.  
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 *  -# Compute the fractional portion (fract) of the table index.
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 *  -# Calculation of wa, wb, wc, wd    
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 *  -# The final result equals <code>a*wa + b*wb + c*wc + d*wd</code>  
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 *  -# The final result equals <code>(1.0f-fract)*a + fract*b;</code>
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 *  
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 *
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 * where  
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 * where
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 * <pre>    
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 * <pre>
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 *    a=Table[index-1];    
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 *    b=Table[index+0];    
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 *    b=Table[index+0];
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 *    c=Table[index+1];    
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 *    c=Table[index+1];
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 *    d=Table[index+2];    
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 * </pre>  
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 * </pre>
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 * and  
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 * <pre>    
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 *    wa=-(1/6)*fract.^3 + (1/2)*fract.^2 - (1/3)*fract;    
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 *    wb=(1/2)*fract.^3 - fract.^2 - (1/2)*fract + 1;    
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 *    wc=-(1/2)*fract.^3+(1/2)*fract.^2+fract;    
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 *    wd=(1/6)*fract.^3 - (1/6)*fract;    
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 * </pre>    
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 */
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 */
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 /**    
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 /**
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 * @addtogroup cos    
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 * @addtogroup cos
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 * @{    
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 * @{
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 */
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 */
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/**  
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/**
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 * @brief  Fast approximation to the trigonometric cosine function for floating-point data.  
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 * @brief  Fast approximation to the trigonometric cosine function for floating-point data.
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 * @param[in] x input value in radians.  
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 * @param[in] x input value in radians.
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 * @return cos(x).  
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 * @return cos(x).
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 */
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 */
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float32_t arm_cos_f32(
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float32_t arm_cos_f32(
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  float32_t x)
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  float32_t x)
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{
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{
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  /* Return the output value */
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  /* Return the output value */
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  return (cosVal);
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  return (cosVal);
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}
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}
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/**    
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/**
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 * @} end of cos group    
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 * @} end of cos group
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 */
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 */