/* ----------------------------------------------------------------------
* Copyright (C) 2010-2014 ARM Limited. All rights reserved.
*
* $Date: 12. March 2014
* $Revision: V1.4.4
*
* Project: CMSIS DSP Library
* Title: arm_cmplx_mag_f32.c
*
* Description: Floating-point complex magnitude.
*
* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* - Neither the name of ARM LIMITED nor the names of its contributors
* may be used to endorse or promote products derived from this
* software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
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* ---------------------------------------------------------------------------- */
#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 */ #ifndef ARM_MATH_CM0_FAMILY /* 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 /* #ifndef ARM_MATH_CM0_FAMILY */ } /** * @} end of cmplx_mag group */