xmclib/CMSIS/DSP_Lib/Source/ComplexMathFunctions/arm_cmplx_mag_f32.c
2024-10-17 17:09:59 +02:00

153 lines
4.3 KiB
C

/* ----------------------------------------------------------------------
* 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
*/