diff options
Diffstat (limited to 'Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f32.c')
| -rw-r--r-- | Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f32.c | 323 |
1 files changed, 188 insertions, 135 deletions
diff --git a/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f32.c b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f32.c index c0f731de6..3c325b135 100644 --- a/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f32.c +++ b/Drivers/CMSIS/DSP/Source/StatisticsFunctions/arm_var_f32.c @@ -3,13 +3,13 @@ * Title: arm_var_f32.c * Description: Variance of the elements of a floating-point vector * - * $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 * @@ -29,153 +29,206 @@ #include "arm_math.h" /** - * @ingroup groupStats + @ingroup groupStats */ /** - * @defgroup variance Variance - * - * Calculates the variance of the elements in the input vector. - * The underlying algorithm used is the direct method sometimes referred to as the two-pass method: - * - * <pre> - * Result = sum(element - meanOfElements)^2) / numElement - 1 - * - * where, meanOfElements = ( pSrc[0] * pSrc[0] + pSrc[1] * pSrc[1] + ... + pSrc[blockSize-1] ) / blockSize - * - * </pre> - * - * There are separate functions for floating point, Q31, and Q15 data types. + @defgroup variance Variance + + Calculates the variance of the elements in the input vector. + The underlying algorithm used is the direct method sometimes referred to as the two-pass method: + + <pre> + Result = sum(element - meanOfElements)^2) / numElement - 1 + + meanOfElements = ( pSrc[0] * pSrc[0] + pSrc[1] * pSrc[1] + ... + pSrc[blockSize-1] ) / blockSize + </pre> + + There are separate functions for floating point, Q31, and Q15 data types. */ /** - * @addtogroup variance - * @{ + @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. + @brief Variance of the elements of a floating-point vector. + @param[in] pSrc points to the input vector + @param[in] blockSize number of samples in input vector + @param[out] pResult variance value returned here + @return none */ - +#if defined(ARM_MATH_NEON_EXPERIMENTAL) void arm_var_f32( - float32_t * pSrc, + const float32_t * pSrc, uint32_t blockSize, float32_t * pResult) { - float32_t fMean, fValue; - uint32_t blkCnt; /* loop counter */ - float32_t * pInput = pSrc; - float32_t sum = 0.0f; - float32_t fSum = 0.0f; - #if defined(ARM_MATH_DSP) - float32_t in1, in2, in3, in4; - #endif - - if (blockSize <= 1U) - { - *pResult = 0; - return; - } - - #if defined(ARM_MATH_DSP) - /* Run the below code for Cortex-M4 and Cortex-M7 */ - - /*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]) */ - in1 = *pInput++; - in2 = *pInput++; - in3 = *pInput++; - in4 = *pInput++; - - sum += in1; - sum += in2; - sum += in3; - sum += in4; - - /* 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 or Cortex-M3 */ - - /* Loop over blockSize number of values */ - blkCnt = blockSize; - - #endif - - while (blkCnt > 0U) - { - /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */ - sum += *pInput++; - - /* Decrement the loop counter */ - blkCnt--; - } - - /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) / blockSize */ - fMean = sum / (float32_t) blockSize; - - pInput = pSrc; - - #if defined(ARM_MATH_DSP) - - /*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) - { - fValue = *pInput++ - fMean; - fSum += fValue * fValue; - fValue = *pInput++ - fMean; - fSum += fValue * fValue; - fValue = *pInput++ - fMean; - fSum += fValue * fValue; - fValue = *pInput++ - fMean; - fSum += fValue * fValue; - - /* Decrement the loop counter */ - blkCnt--; - } - - blkCnt = blockSize % 0x4U; - #else - /* Run the below code for Cortex-M0 or Cortex-M3 */ - - /* Loop over blockSize number of values */ - blkCnt = blockSize; - #endif - - while (blkCnt > 0U) - { - fValue = *pInput++ - fMean; - fSum += fValue * fValue; - - /* Decrement the loop counter */ - blkCnt--; - } - - /* Variance */ - *pResult = fSum / (float32_t)(blockSize - 1.0f); + float32_t mean; + + float32_t sum = 0.0f; /* accumulator */ + float32_t in; /* Temporary variable to store input value */ + uint32_t blkCnt; /* loop counter */ + + float32x4_t sumV = vdupq_n_f32(0.0f); /* Temporary result storage */ + float32x2_t sumV2; + float32x4_t inV; + float32x4_t avg; + + arm_mean_f32(pSrc,blockSize,&mean); + avg = vdupq_n_f32(mean); + + blkCnt = blockSize >> 2U; + + /* 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[2] * A[2] + ... + A[blockSize-1] * A[blockSize-1] */ + /* Compute Power and then store the result in a temporary variable, sum. */ + inV = vld1q_f32(pSrc); + inV = vsubq_f32(inV, avg); + sumV = vmlaq_f32(sumV, inV, inV); + pSrc += 4; + + /* Decrement the loop counter */ + blkCnt--; + } + + sumV2 = vpadd_f32(vget_low_f32(sumV),vget_high_f32(sumV)); + sum = sumV2[0] + sumV2[1]; + + /* 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[2] * A[2] + ... + A[blockSize-1] * A[blockSize-1] */ + /* compute power and then store the result in a temporary variable, sum. */ + in = *pSrc++; + in = in - mean; + sum += in * in; + + /* Decrement the loop counter */ + blkCnt--; + } + + /* Variance */ + *pResult = sum / (float32_t)(blockSize - 1.0f); + +} + +#else +void arm_var_f32( + const float32_t * pSrc, + uint32_t blockSize, + float32_t * pResult) +{ + uint32_t blkCnt; /* Loop counter */ + float32_t sum = 0.0f; /* Temporary result storage */ + float32_t fSum = 0.0f; + float32_t fMean, fValue; + const float32_t * pInput = pSrc; + + if (blockSize <= 1U) + { + *pResult = 0; + return; + } + +#if defined (ARM_MATH_LOOPUNROLL) + + /* Loop unrolling: Compute 4 outputs at a time */ + blkCnt = blockSize >> 2U; + + while (blkCnt > 0U) + { + /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */ + + sum += *pInput++; + sum += *pInput++; + sum += *pInput++; + sum += *pInput++; + + + /* Decrement loop counter */ + blkCnt--; + } + + /* Loop unrolling: Compute remaining outputs */ + blkCnt = blockSize % 0x4U; + +#else + + /* Initialize blkCnt with number of samples */ + blkCnt = blockSize; + +#endif /* #if defined (ARM_MATH_LOOPUNROLL) */ + + while (blkCnt > 0U) + { + /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */ + + sum += *pInput++; + + /* Decrement loop counter */ + blkCnt--; + } + + /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) / blockSize */ + fMean = sum / (float32_t) blockSize; + + pInput = pSrc; + +#if defined (ARM_MATH_LOOPUNROLL) + + /* Loop unrolling: Compute 4 outputs at a time */ + blkCnt = blockSize >> 2U; + + while (blkCnt > 0U) + { + fValue = *pInput++ - fMean; + fSum += fValue * fValue; + + fValue = *pInput++ - fMean; + fSum += fValue * fValue; + + fValue = *pInput++ - fMean; + fSum += fValue * fValue; + + fValue = *pInput++ - fMean; + fSum += fValue * fValue; + + /* Decrement loop counter */ + blkCnt--; + } + + /* Loop unrolling: Compute remaining outputs */ + blkCnt = blockSize % 0x4U; + +#else + + /* Initialize blkCnt with number of samples */ + blkCnt = blockSize; + +#endif /* #if defined (ARM_MATH_LOOPUNROLL) */ + + while (blkCnt > 0U) + { + fValue = *pInput++ - fMean; + fSum += fValue * fValue; + + /* Decrement loop counter */ + blkCnt--; + } + + /* Variance */ + *pResult = fSum / (float32_t)(blockSize - 1.0f); } +#endif /* #if defined(ARM_MATH_NEON) */ /** - * @} end of variance group + @} end of variance group */ |