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authorrihab kouki <rihab.kouki@st.com>2020-07-28 11:24:49 +0100
committerrihab kouki <rihab.kouki@st.com>2020-07-28 11:24:49 +0100
commit96d6da4e252b06dcfdc041e7df23e86161c33007 (patch)
treea262f59bb1db7ec7819acae435f5049cbe5e2354 /DSP/Source/FastMathFunctions/arm_sin_q15.c
parent9f95ff5b6ba01db09552b84a0ab79607060a2666 (diff)
downloadst-cmsis-core-lowfat-master.tar.gz
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Official ARM version: v5.6.0HEADmaster
Diffstat (limited to 'DSP/Source/FastMathFunctions/arm_sin_q15.c')
-rw-r--r--DSP/Source/FastMathFunctions/arm_sin_q15.c39
1 files changed, 20 insertions, 19 deletions
diff --git a/DSP/Source/FastMathFunctions/arm_sin_q15.c b/DSP/Source/FastMathFunctions/arm_sin_q15.c
index 7c8f627..1f0c2bf 100644
--- a/DSP/Source/FastMathFunctions/arm_sin_q15.c
+++ b/DSP/Source/FastMathFunctions/arm_sin_q15.c
@@ -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
+ @ingroup groupFastMath
*/
- /**
- * @addtogroup sin
- * @{
+/**
+ @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).
+ @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
*/