/* ----------------------------------------------------------------------
* 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 pSrc
points to the source data and
* pDst
points to the where the result should be written.
* numSamples
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 2*numSamples
values;
* the output array has a total of numSamples
values.
* The underlying algorithm is used:
*
*
* for(n=0; n* * 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 */