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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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42
DSP/Source/FastMathFunctions/arm_sin_q31.c
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@ -3,13 +3,13 @@
* Title: arm_sin_q31.c
* Description: Fast sine calculation for Q31 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
*
@ -30,27 +30,28 @@
#include "arm_common_tables.h"
/**
* @ingroup groupFastMath
*/
/**
* @addtogroup sin
* @{
@ingroup groupFastMath
*/
/**
* @brief Fast approximation to the trigonometric sine function for Q31 data.
* @param[in] x Scaled input value in radians.
* @return sin(x).
*
* The Q31 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 Q31 data.
@param[in] x Scaled input value in radians
@return sin(x)
The Q31 input value is in the range [0 +0.9999] and is mapped to a radian value in the range [0 2*PI).
*/
q31_t arm_sin_q31(
q31_t x)
{
q31_t sinVal; /* Temporary variables for input, output */
int32_t index; /* Index variables */
q31_t a, b; /* Four nearest output values */
int32_t index; /* Index variable */
q31_t a, b; /* Two nearest output values */
q31_t fract; /* Temporary values for fractional values */
/* Calculate the nearest index */
@ -64,12 +65,13 @@ q31_t arm_sin_q31(
b = sinTable_q31[index+1];
/* Linear interpolation process */
sinVal = (q63_t)(0x80000000-fract)*a >> 32;
sinVal = (q31_t)((((q63_t)sinVal << 32) + ((q63_t)fract*b)) >> 32);
sinVal = (q63_t) (0x80000000 - fract) * a >> 32;
sinVal = (q31_t) ((((q63_t) sinVal << 32) + ((q63_t) fract * b)) >> 32);
return sinVal << 1;
/* Return output value */
return (sinVal << 1);
}
/**
* @} end of sin group
@} end of sin group
*/