1 /* ----------------------------------------------------------------------
2 * Project: CMSIS DSP Library
3 * Title: arm_mean_f64.c
4 * Description: Mean value of a floating-point vector
5 *
6 * $Date: 03 June 2022
7 * $Revision: V1.10.1
8 *
9 * Target Processor: Cortex-M and Cortex-A cores
10 * -------------------------------------------------------------------- */
11 /*
12 * Copyright (C) 2010-2021 ARM Limited or its affiliates. All rights reserved.
13 *
14 * SPDX-License-Identifier: Apache-2.0
15 *
16 * Licensed under the Apache License, Version 2.0 (the License); you may
17 * not use this file except in compliance with the License.
18 * You may obtain a copy of the License at
19 *
20 * www.apache.org/licenses/LICENSE-2.0
21 *
22 * Unless required by applicable law or agreed to in writing, software
23 * distributed under the License is distributed on an AS IS BASIS, WITHOUT
24 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
25 * See the License for the specific language governing permissions and
26 * limitations under the License.
27 */
28
29 #include "dsp/statistics_functions.h"
30
31 /**
32 @ingroup groupStats
33 */
34
35
36 /**
37 @addtogroup mean
38 @{
39 */
40
41 /**
42 @brief Mean value of a floating-point vector.
43 @param[in] pSrc points to the input vector.
44 @param[in] blockSize number of samples in input vector.
45 @param[out] pResult mean value returned here.
46 */
47
48 #if defined(ARM_MATH_NEON) && defined(__aarch64__)
49
arm_mean_f64(const float64_t * pSrc,uint32_t blockSize,float64_t * pResult)50 ARM_DSP_ATTRIBUTE void arm_mean_f64(
51 const float64_t * pSrc,
52 uint32_t blockSize,
53 float64_t * pResult)
54 {
55 uint32_t blkCnt; /* Loop counter */
56 float64x2_t vSum = vdupq_n_f64(0.0);
57 float64_t sum = 0.; /* Temporary result storage */
58 float64x2_t afterLoad ;
59 /* Initialize blkCnt with number of samples */
60 blkCnt = blockSize >> 1U;
61
62
63 while (blkCnt > 0U)
64 {
65 /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */
66
67 afterLoad = vld1q_f64(pSrc);
68 vSum = vaddq_f64(vSum, afterLoad);
69 pSrc += 2;
70 /* Decrement loop counter */
71 blkCnt--;
72
73
74 }
75 sum = vaddvq_f64(vSum);
76
77 blkCnt = blockSize & 1;
78
79 while (blkCnt > 0U)
80 {
81 /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */
82 sum += *pSrc++;
83
84 /* Decrement loop counter */
85 blkCnt--;
86 }
87 *pResult = (sum/blockSize);
88 }
89 #else
arm_mean_f64(const float64_t * pSrc,uint32_t blockSize,float64_t * pResult)90 ARM_DSP_ATTRIBUTE void arm_mean_f64(
91 const float64_t * pSrc,
92 uint32_t blockSize,
93 float64_t * pResult)
94 {
95 uint32_t blkCnt; /* Loop counter */
96 float64_t sum = 0.; /* Temporary result storage */
97
98 /* Initialize blkCnt with number of samples */
99 blkCnt = blockSize;
100
101 while (blkCnt > 0U)
102 {
103 /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) */
104 sum += *pSrc++;
105
106 /* Decrement loop counter */
107 blkCnt--;
108 }
109
110 /* C = (A[0] + A[1] + A[2] + ... + A[blockSize-1]) / blockSize */
111 /* Store result to destination */
112 *pResult = (sum / blockSize);
113 }
114 #endif
115 /**
116 @} end of mean group
117 */
118
