/* ----------------------------------------------------------------------
* Copyright (C) 2010 ARM Limited. All rights reserved.
*
* $Date: 15. July 2011
* $Revision: V1.0.10
*
* Project: CMSIS DSP Library
* Title: arm_cmplx_conj_f32.c
*
* Description: Floating-point complex conjugate.
*
* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
*
* Version 1.0.10 2011/7/15
* Big Endian support added and Merged M0 and M3/M4 Source code.
*
* Version 1.0.3 2010/11/29
* Re-organized the CMSIS folders and updated documentation.
*
* Version 1.0.2 2010/11/11
* Documentation updated.
*
* Version 1.0.1 2010/10/05
* Production release and review comments incorporated.
*
* Version 1.0.0 2010/09/20
* Production release and review comments incorporated.
* ---------------------------------------------------------------------------- */
#include "arm_math.h"
/**
* @ingroup groupCmplxMath
*/
/**
* @defgroup cmplx_conj Complex Conjugate
*
* Conjugates 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
* and the data in each array is stored in an interleaved fashion
* (real, imag, real, imag, ...).
* Each array has a total of 2*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_conj * @{ */ /** * @brief Floating-point complex conjugate. * @param *pSrc points to the input vector * @param *pDst points to the output vector * @param numSamples number of complex samples in each vector * @return none. */ void arm_cmplx_conj_f32( float32_t * pSrc, float32_t * pDst, uint32_t numSamples) { #ifndef ARM_MATH_CM0 /* 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]+jC[1] = A[0]+ j (-1) A[1] */ /* Calculate Complex Conjugate and then store the results in the destination buffer. */ *pDst++ = *pSrc++; *pDst++ = -*pSrc++; *pDst++ = *pSrc++; *pDst++ = -*pSrc++; *pDst++ = *pSrc++; *pDst++ = -*pSrc++; *pDst++ = *pSrc++; *pDst++ = -*pSrc++; /* 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]+jC[1] = A[0]+ j (-1) A[1] */ /* Calculate Complex Conjugate and then store the results in the destination buffer. */ *pDst++ = *pSrc++; *pDst++ = -*pSrc++; /* Decrement the loop counter */ blkCnt--; } #else /* Run the below code for Cortex-M0 */ while(numSamples > 0u) { /* realOut + j (imagOut) = realIn + j (-1) imagIn */ /* Calculate Complex Conjugate and then store the results in the destination buffer. */ *pDst++ = *pSrc++; *pDst++ = -*pSrc++; /* Decrement the loop counter */ numSamples--; } #endif /* #ifndef ARM_MATH_CM0 */ } /** * @} end of cmplx_conj group */