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Official ARM version: v5.6.0

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rihab kouki 2020-07-28 11:24:49 +01:00
parent 9f95ff5b6b
commit 96d6da4e25
2939 changed files with 339304 additions and 113320 deletions
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43
DSP/Source/FastMathFunctions/arm_sin_q15.c
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@ -3,13 +3,13 @@
* Title: arm_sin_q15.c
* Description: Fast sine calculation for Q15 values
*
* $Date: 27. January 2017
* $Revision: V.1.5.1
* $Date: 18. March 2019
* $Revision: V1.6.0
*
* Target Processor: Cortex-M cores
* -------------------------------------------------------------------- */
/*
* Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved.
* Copyright (C) 2010-2019 ARM Limited or its affiliates. All rights reserved.
*
* SPDX-License-Identifier: Apache-2.0
*
@ -30,28 +30,28 @@
#include "arm_common_tables.h"
/**
* @ingroup groupFastMath
*/
/**
* @addtogroup sin
* @{
@ingroup groupFastMath
*/
/**
* @brief Fast approximation to the trigonometric sine function for Q15 data.
* @param[in] x Scaled input value in radians.
* @return sin(x).
*
* The Q15 input value is in the range [0 +0.9999] and is mapped to a radian value in the range [0 2*pi).
@addtogroup sin
@{
*/
/**
@brief Fast approximation to the trigonometric sine function for Q15 data.
@param[in] x Scaled input value in radians
@return sin(x)
The Q15 input value is in the range [0 +0.9999] and is mapped to a radian value in the range [0 2*PI).
*/
q15_t arm_sin_q15(
q15_t x)
{
q15_t sinVal; /* Temporary variables for input, output */
int32_t index; /* Index variables */
q15_t a, b; /* Four nearest output values */
q15_t sinVal; /* Temporary input, output variables */
int32_t index; /* Index variable */
q15_t a, b; /* Two nearest output values */
q15_t fract; /* Temporary values for fractional values */
/* Calculate the nearest index */
@ -65,12 +65,13 @@ q15_t arm_sin_q15(
b = sinTable_q15[index+1];
/* Linear interpolation process */
sinVal = (q31_t)(0x8000-fract)*a >> 16;
sinVal = (q15_t)((((q31_t)sinVal << 16) + ((q31_t)fract*b)) >> 16);
sinVal = (q31_t) (0x8000 - fract) * a >> 16;
sinVal = (q15_t) ((((q31_t) sinVal << 16) + ((q31_t) fract * b)) >> 16);
return sinVal << 1;
/* Return output value */
return (sinVal << 1);
}
/**
* @} end of sin group
@} end of sin group
*/