text: /* ----------------------------------------------------------------------
   * Project:      CMSIS DSP Library
   * Title:        arm_mean_f32.c
   * Description:  Mean value of a floating-point vector
   *
   * $Date:        27. January 2017
   * $Revision:    V.1.5.1
   *
   * Target Processor: Cortex-M cores
   * -------------------------------------------------------------------- */
  /*
   * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved.
   *
   * SPDX-License-Identifier: Apache-2.0
   *
   * Licensed under the Apache License, Version 2.0 (the License); you may
   * not use this file except in compliance with the License.
   * You may obtain a copy of the License at
   *
   * www.apache.org/licenses/LICENSE-2.0
   *
   * Unless required by applicable law or agreed to in writing, software
   * distributed under the License is distributed on an AS IS BASIS, WITHOUT
   * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
   * See the License for the specific language governing permissions and
   * limitations under the License.
   */
  
  #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(
    const float32_t * pSrc,
    uint32_t blockSize,
    float32_t * pResult)
  {
    float32_t sum = 0.0f;                          /* Temporary result storage */
    uint32_t blkCnt;                               /* loop counter */
  
  #if defined (ARM_MATH_DSP)
    /* Run the below code for Cortex-M4 and Cortex-M3 */
  
    float32_t in1, in2, in3, in4;
  
    /*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 = *pSrc++;
      in2 = *pSrc++;
      in3 = *pSrc++;
      in4 = *pSrc++;
  
      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 */
  
    /* Loop over blockSize number of values */
    blkCnt = blockSize;
  
  #endif /* #if defined (ARM_MATH_DSP) */
  
    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
   */
  