|
|
/* ----------------------------------------------------------------------
|
|
|
* Copyright (C) 2010 ARM Limited. All rights reserved.
|
|
|
*
|
|
|
* $Date: 15. July 2011
|
|
|
* $Revision: V1.0.10
|
|
|
*
|
|
|
* Project: CMSIS DSP Library
|
|
|
* Title: arm_mean_f32.c
|
|
|
*
|
|
|
* Description: Mean value of a floating-point vector.
|
|
|
*
|
|
|
* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
|
|
|
*
|
|
|
* Version 1.0.10 2011/7/15
|
|
|
* Big Endian support added and Merged M0 and M3/M4 Source code.
|
|
|
*
|
|
|
* Version 1.0.3 2010/11/29
|
|
|
* Re-organized the CMSIS folders and updated documentation.
|
|
|
*
|
|
|
* Version 1.0.2 2010/11/11
|
|
|
* Documentation updated.
|
|
|
*
|
|
|
* Version 1.0.1 2010/10/05
|
|
|
* Production release and review comments incorporated.
|
|
|
*
|
|
|
* Version 1.0.0 2010/09/20
|
|
|
* Production release and review comments incorporated.
|
|
|
* ---------------------------------------------------------------------------- */
|
|
|
|
|
|
#include "arm_math.h"
|
|
|
|
|
|
/**
|
|
|
* @ingroup groupStats
|
|
|
*/
|
|
|
|
|
|
/**
|
|
|
* @defgroup mean Mean
|
|
|
*
|
|
|
* Calculates the mean of the input vector. Mean is defined as the average of the elements in the vector.
|
|
|
* The underlying algorithm is used:
|
|
|
*
|
|
|
* <pre>
|
|
|
* Result = (pSrc[0] + pSrc[1] + pSrc[2] + ... + pSrc[blockSize-1]) / blockSize;
|
|
|
* </pre>
|
|
|
*
|
|
|
* There are separate functions for floating-point, Q31, Q15, and Q7 data types.
|
|
|
*/
|
|
|
|
|
|
/**
|
|
|
* @addtogroup mean
|
|
|
* @{
|
|
|
*/
|
|
|
|
|
|
|
|
|
/**
|
|
|
* @brief Mean value of a floating-point vector.
|
|
|
* @param[in] *pSrc points to the input vector
|
|
|
* @param[in] blockSize length of the input vector
|
|
|
* @param[out] *pResult mean value returned here
|
|
|
* @return none.
|
|
|
*/
|
|
|
|
|
|
|
|
|
void arm_mean_f32(
|
|
|
float32_t * pSrc,
|
|
|
uint32_t blockSize,
|
|
|
float32_t * pResult)
|
|
|
{
|
|
|
float32_t sum = 0.0f; /* Temporary result storage */
|
|
|
uint32_t blkCnt; /* loop counter */
|
|
|
|
|
|
#ifndef ARM_MATH_CM0
|
|
|
|
|
|
/* Run the below code for Cortex-M4 and Cortex-M3 */
|
|
|
|
|
|
/*loop Unrolling */
|
|
|
blkCnt = blockSize >> 2u;
|
|
|
|
|
|
/* First part of the processing with loop unrolling. Compute 4 outputs at a time.
|
|
|
** a second loop below computes the remaining 1 to 3 samples. */
|
|
|
while(blkCnt > 0u)
|
|
|
{
|
|
|
/* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */
|
|
|
sum += *pSrc++;
|
|
|
sum += *pSrc++;
|
|
|
sum += *pSrc++;
|
|
|
sum += *pSrc++;
|
|
|
|
|
|
/* Decrement the loop counter */
|
|
|
blkCnt--;
|
|
|
}
|
|
|
|
|
|
/* If the blockSize is not a multiple of 4, compute any remaining output samples here.
|
|
|
** No loop unrolling is used. */
|
|
|
blkCnt = blockSize % 0x4u;
|
|
|
|
|
|
#else
|
|
|
|
|
|
/* Run the below code for Cortex-M0 */
|
|
|
|
|
|
/* Loop over blockSize number of values */
|
|
|
blkCnt = blockSize;
|
|
|
|
|
|
#endif /* #ifndef ARM_MATH_CM0 */
|
|
|
|
|
|
while(blkCnt > 0u)
|
|
|
{
|
|
|
/* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */
|
|
|
sum += *pSrc++;
|
|
|
|
|
|
/* Decrement the loop counter */
|
|
|
blkCnt--;
|
|
|
}
|
|
|
|
|
|
/* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) / blockSize */
|
|
|
/* Store the result to the destination */
|
|
|
*pResult = sum / (float32_t) blockSize;
|
|
|
}
|
|
|
|
|
|
/**
|
|
|
* @} end of mean group
|
|
|
*/
|
|
|
|
