summaryrefslogtreecommitdiff
path: root/Blink/Drivers/CMSIS/DSP/Source/ComplexMathFunctions/arm_cmplx_mag_f32.c
blob: 6c8be8f9184d72a44d1356fc7e40490fbe0f2dcb (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
/* ----------------------------------------------------------------------
 * Project:      CMSIS DSP Library
 * Title:        arm_cmplx_mag_f32.c
 * Description:  Floating-point complex magnitude
 *
 * $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 groupCmplxMath
 */

/**
 * @defgroup cmplx_mag Complex Magnitude
 *
 * Computes the magnitude of the elements of a complex data vector.
 *
 * The <code>pSrc</code> points to the source data and
 * <code>pDst</code> points to the where the result should be written.
 * <code>numSamples</code> specifies the number of complex samples
 * in the input array and the data is stored in an interleaved fashion
 * (real, imag, real, imag, ...).
 * The input array has a total of <code>2*numSamples</code> values;
 * the output array has a total of <code>numSamples</code> values.
 * The underlying algorithm is used:
 *
 * <pre>
 * for(n=0; n<numSamples; n++) {
 *     pDst[n] = sqrt(pSrc[(2*n)+0]^2 + pSrc[(2*n)+1]^2);
 * }
 * </pre>
 *
 * There are separate functions for floating-point, Q15, and Q31 data types.
 */

/**
 * @addtogroup cmplx_mag
 * @{
 */
/**
 * @brief Floating-point complex magnitude.
 * @param[in]       *pSrc points to complex input buffer
 * @param[out]      *pDst points to real output buffer
 * @param[in]       numSamples number of complex samples in the input vector
 * @return none.
 *
 */


void arm_cmplx_mag_f32(
  float32_t * pSrc,
  float32_t * pDst,
  uint32_t numSamples)
{
  float32_t realIn, imagIn;                      /* Temporary variables to hold input values */

#if defined (ARM_MATH_DSP)

  /* Run the below code for Cortex-M4 and Cortex-M3 */
  uint32_t blkCnt;                               /* loop counter */

  /*loop Unrolling */
  blkCnt = numSamples >> 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[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
    realIn = *pSrc++;
    imagIn = *pSrc++;
    /* store the result in the destination buffer. */
    arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);

    realIn = *pSrc++;
    imagIn = *pSrc++;
    arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);

    realIn = *pSrc++;
    imagIn = *pSrc++;
    arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);

    realIn = *pSrc++;
    imagIn = *pSrc++;
    arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);


    /* Decrement the loop counter */
    blkCnt--;
  }

  /* If the numSamples is not a multiple of 4, compute any remaining output samples here.
   ** No loop unrolling is used. */
  blkCnt = numSamples % 0x4U;

  while (blkCnt > 0U)
  {
    /* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
    realIn = *pSrc++;
    imagIn = *pSrc++;
    /* store the result in the destination buffer. */
    arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);

    /* Decrement the loop counter */
    blkCnt--;
  }

#else

  /* Run the below code for Cortex-M0 */

  while (numSamples > 0U)
  {
    /* out = sqrt((real * real) + (imag * imag)) */
    realIn = *pSrc++;
    imagIn = *pSrc++;
    /* store the result in the destination buffer. */
    arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);

    /* Decrement the loop counter */
    numSamples--;
  }

#endif /* #if defined (ARM_MATH_DSP) */

}

/**
 * @} end of cmplx_mag group
 */