1  /* ----------------------------------------------------------------------
 2   * Project:      CMSIS DSP Library
 3   * Title:        arm_quaternion_conjugate_f32.c
 4   * Description:  Floating-point quaternion conjugate
 5   *
 6   * $Date:        23 April 2021
 7   * $Revision:    V1.9.0
 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/quaternion_math_functions.h"
30  #include <math.h>
31  
32  /**
33    @ingroup groupQuaternionMath
34   */
35  
36  /**
37    @defgroup QuatConjugate Quaternion Conjugate
38  
39    Compute the conjugate of a quaternion.
40   */
41  
42  /**
43    @addtogroup QuatConjugate
44    @{
45   */
46  
47  /**
48    @brief         Floating-point quaternion conjugates.
49    @param[in]     pInputQuaternions            points to the input vector of quaternions
50    @param[out]    pConjugateQuaternions        points to the output vector of conjugate quaternions
51    @param[in]     nbQuaternions                number of quaternions in each vector
52    @return        none
53   */
54  
55  #if defined(ARM_MATH_MVEF) && !defined(ARM_MATH_AUTOVECTORIZE)
56  
57  #include "arm_helium_utils.h"
58  void arm_quaternion_conjugate_f32(const float32_t *pInputQuaternions, 
59      float32_t *pConjugateQuaternions, 
60      uint32_t nbQuaternions)
61  {
62     f32x4_t vec1;
63  
64     for(uint32_t i=0; i < nbQuaternions; i++)
65     {
66        vec1 = vld1q(pInputQuaternions);
67        
68  
69        vec1 = vsetq_lane_f32(-vgetq_lane(vec1, 0),vec1,0);
70        vec1 = vnegq_f32(vec1);
71  
72        vst1q(pConjugateQuaternions, vec1);
73  
74  
75        pInputQuaternions   += 4;
76        pConjugateQuaternions += 4;
77     }
78  }
79  #else
80  void arm_quaternion_conjugate_f32(const float32_t *pInputQuaternions, 
81      float32_t *pConjugateQuaternions, 
82      uint32_t nbQuaternions)
83  {
84     uint32_t i;
85     for(i=0; i < nbQuaternions; i++)
86     {
87  
88        pConjugateQuaternions[4 * i + 0] = pInputQuaternions[4 * i + 0];
89        pConjugateQuaternions[4 * i + 1] = -pInputQuaternions[4 * i + 1];
90        pConjugateQuaternions[4 * i + 2] = -pInputQuaternions[4 * i + 2];
91        pConjugateQuaternions[4 * i + 3] = -pInputQuaternions[4 * i + 3];
92     }
93  }
94  #endif /* defined(ARM_MATH_MVEF) && !defined(ARM_MATH_AUTOVECTORIZE) */
95  
96  /**
97    @} end of QuatConjugate group
98   */