1
2 /* ----------------------------------------------------------------------
3 * Project: CMSIS DSP Library
4 * Title: arm_hamming_distance.c
5 * Description: Hamming distance between two vectors
6 *
7 * $Date: 23 April 2021
8 * $Revision: V1.9.0
9 *
10 * Target Processor: Cortex-M and Cortex-A cores
11 * -------------------------------------------------------------------- */
12 /*
13 * Copyright (C) 2010-2021 ARM Limited or its affiliates. All rights reserved.
14 *
15 * SPDX-License-Identifier: Apache-2.0
16 *
17 * Licensed under the Apache License, Version 2.0 (the License); you may
18 * not use this file except in compliance with the License.
19 * You may obtain a copy of the License at
20 *
21 * www.apache.org/licenses/LICENSE-2.0
22 *
23 * Unless required by applicable law or agreed to in writing, software
24 * distributed under the License is distributed on an AS IS BASIS, WITHOUT
25 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
26 * See the License for the specific language governing permissions and
27 * limitations under the License.
28 */
29
30 #include "dsp/distance_functions.h"
31 #include <limits.h>
32 #include <math.h>
33
34
35 extern void arm_boolean_distance_TF_FT(const uint32_t *pA
36 , const uint32_t *pB
37 , uint32_t numberOfBools
38 , uint32_t *cTF
39 , uint32_t *cFT
40 );
41
42 /**
43 @addtogroup BoolDist
44 @{
45 */
46
47
48 /**
49 * @brief Hamming distance between two vectors
50 *
51 * @param[in] pA First vector of packed booleans
52 * @param[in] pB Second vector of packed booleans
53 * @param[in] numberOfBools Number of booleans
54 * @return distance
55 *
56 */
57
arm_hamming_distance(const uint32_t * pA,const uint32_t * pB,uint32_t numberOfBools)58 float32_t arm_hamming_distance(const uint32_t *pA, const uint32_t *pB, uint32_t numberOfBools)
59 {
60 uint32_t ctf=0,cft=0;
61
62 arm_boolean_distance_TF_FT(pA, pB, numberOfBools, &ctf, &cft);
63
64 return(1.0*(ctf + cft) / numberOfBools);
65 }
66
67
68 /**
69 * @} end of BoolDist group
70 */
71
