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Added Oplayer BSP, Fixed bug on GPIO library(gpiosetval change all the port...
Added Oplayer BSP, Fixed bug on GPIO library(gpiosetval change all the port instead of the desired bit).
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arm_var_f32.c
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/ lib / src / stm32f4 / CPU / CMSIS / DSP_Lib / Source / StatisticsFunctions / arm_var_f32.c
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jeandet@pc-de-jeandet3.LAB-LPP.LOCAL
Added ARM CMSIS for fast math and circle drawing function for ili9328 driver.
 r41 /* ----------------------------------------------------------------------
* Copyright (C) 2010 ARM Limited. All rights reserved.
*
* $Date: 15. July 2011
* $Revision: V1.0.10
*
* Project: CMSIS DSP Library
* Title: arm_var_f32.c
*
* Description: Variance of the elements 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 variance Variance
*
* Calculates the variance of the elements in the input vector.
* The underlying algorithm is used:
*
* <pre>
* Result = (sumOfSquares - sum<sup>2</sup> / blockSize) / (blockSize - 1)
*
* where, sumOfSquares = pSrc[0] * pSrc[0] + pSrc[1] * pSrc[1] + ... + pSrc[blockSize-1] * pSrc[blockSize-1]
*
* sum = pSrc[0] + pSrc[1] + pSrc[2] + ... + pSrc[blockSize-1]
* </pre>
*
* There are separate functions for floating point, Q31, and Q15 data types.
*/
/**
* @addtogroup variance
* @{
*/
/**
* @brief Variance of the elements of a floating-point vector.
* @param[in] *pSrc points to the input vector
* @param[in] blockSize length of the input vector
* @param[out] *pResult variance value returned here
* @return none.
*
*/
void arm_var_f32(
float32_t * pSrc,
uint32_t blockSize,
float32_t * pResult)
{
#ifndef ARM_MATH_CM0
/* Run the below code for Cortex-M4 and Cortex-M3 */
float32_t sum = (float32_t) 0.0; /* Accumulator */
float32_t meanOfSquares, mean, in, squareOfMean; /* Temporary variables */
uint32_t blkCnt; /* loop counter */
float32_t *pIn; /* Temporary pointer */
/* updating temporary pointer */
pIn = pSrc;
/*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[0] + A[1] * A[1] + ... + A[blockSize-1] * A[blockSize-1]) */
/* Compute Sum of squares of the input samples
* and then store the result in a temporary variable, sum. */
in = *pSrc++;
sum += in * in;
in = *pSrc++;
sum += in * in;
in = *pSrc++;
sum += in * in;
in = *pSrc++;
sum += in * in;
/* 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;
while(blkCnt > 0u)
{
/* C = (A[0] * A[0] + A[1] * A[1] + ... + A[blockSize-1] * A[blockSize-1]) */
/* Compute Sum of squares of the input samples
* and then store the result in a temporary variable, sum. */
in = *pSrc++;
sum += in * in;
/* Decrement the loop counter */
blkCnt--;
}
/* Compute Mean of squares of the input samples
* and then store the result in a temporary variable, meanOfSquares. */
meanOfSquares = sum / ((float32_t) blockSize - 1.0f);
/* Reset the accumulator */
sum = 0.0f;
/*loop Unrolling */
blkCnt = blockSize >> 2u;
/* Reset the input working pointer */
pSrc = pIn;
/* 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]) */
/* Compute sum of all input values and then store the result in a temporary variable, sum. */
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;
while(blkCnt > 0u)
{
/* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */
/* Compute sum of all input values and then store the result in a temporary variable, sum. */
sum += *pSrc++;
/* Decrement the loop counter */
blkCnt--;
}
/* Compute mean of all input values */
mean = sum / (float32_t) blockSize;
/* Compute square of mean */
squareOfMean = (mean * mean) * (((float32_t) blockSize) /
((float32_t) blockSize - 1.0f));
/* Compute variance and then store the result to the destination */
*pResult = meanOfSquares - squareOfMean;
#else
/* Run the below code for Cortex-M0 */
float32_t sum = 0.0f; /* Temporary result storage */
float32_t sumOfSquares = 0.0f; /* Sum of squares */
float32_t squareOfSum; /* Square of Sum */
float32_t in; /* input value */
uint32_t blkCnt; /* loop counter */
/* Loop over blockSize number of values */
blkCnt = blockSize;
while(blkCnt > 0u)
{
/* C = (A[0] * A[0] + A[1] * A[1] + ... + A[blockSize-1] * A[blockSize-1]) */
/* Compute Sum of squares of the input samples
* and then store the result in a temporary variable, sumOfSquares. */
in = *pSrc++;
sumOfSquares += in * in;
/* C = (A[0] + A[1] + ... + A[blockSize-1]) */
/* Compute Sum of the input samples
* and then store the result in a temporary variable, sum. */
sum += in;
/* Decrement the loop counter */
blkCnt--;
}
/* Compute the square of sum */
squareOfSum = ((sum * sum) / (float32_t) blockSize);
/* Compute the variance */
*pResult = ((sumOfSquares - squareOfSum) / (float32_t) (blockSize - 1.0f));
#endif /* #ifndef ARM_MATH_CM0 */
}
/**
* @} end of variance group
*/