1 /* ----------------------------------------------------------------------
2 * Project: CMSIS DSP Library
3 * Title: arm_cmplx_mult_cmplx_f64.c
4 * Description: Floating-point complex-by-complex multiplication
5 *
6 * $Date: 13 September 2021
7 * $Revision: V1.10.0
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/complex_math_functions.h"
30
31 /**
32 @ingroup groupCmplxMath
33 */
34
35 /**
36 @addtogroup CmplxByCmplxMult
37 @{
38 */
39
40 /**
41 @brief Floating-point complex-by-complex multiplication.
42 @param[in] pSrcA points to first input vector
43 @param[in] pSrcB points to second input vector
44 @param[out] pDst points to output vector
45 @param[in] numSamples number of samples in each vector
46 */
47
arm_cmplx_mult_cmplx_f64(const float64_t * pSrcA,const float64_t * pSrcB,float64_t * pDst,uint32_t numSamples)48 void arm_cmplx_mult_cmplx_f64(
49 const float64_t * pSrcA,
50 const float64_t * pSrcB,
51 float64_t * pDst,
52 uint32_t numSamples)
53 {
54 uint32_t blkCnt; /* Loop counter */
55 float64_t a, b, c, d; /* Temporary variables to store real and imaginary values */
56
57 /* Initialize blkCnt with number of samples */
58 blkCnt = numSamples;
59
60 while (blkCnt > 0U)
61 {
62 /* C[2 * i ] = A[2 * i] * B[2 * i ] - A[2 * i + 1] * B[2 * i + 1]. */
63 /* C[2 * i + 1] = A[2 * i] * B[2 * i + 1] + A[2 * i + 1] * B[2 * i ]. */
64
65 a = *pSrcA++;
66 b = *pSrcA++;
67 c = *pSrcB++;
68 d = *pSrcB++;
69
70 /* store result in destination buffer. */
71 *pDst++ = (a * c) - (b * d);
72 *pDst++ = (a * d) + (b * c);
73
74 /* Decrement loop counter */
75 blkCnt--;
76 }
77
78 }
79
80 /**
81 @} end of CmplxByCmplxMult group
82 */
83
