/* ----------------------------------------------------------------------
* Copyright (C) 2010 ARM Limited. All rights reserved.
*
* $Date: 15. July 2011
* $Revision: V1.0.10
*
* Project: CMSIS DSP Library
* Title: arm_cmplx_dot_prod_f32.c
*
* Description: Floating-point complex dot product
*
* 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_dot_prod Complex Dot Product
*
* Computes the dot product of two complex vectors.
* The vectors are multiplied element-by-element and then summed.
*
* The pSrcA
points to the first complex input vector and
* pSrcB
points to the second complex input vector.
* 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:
*
* realResult=0; * imagResult=0; * for(n=0; n* * There are separate functions for floating-point, Q15, and Q31 data types. */ /** * @addtogroup cmplx_dot_prod * @{ */ /** * @brief Floating-point complex dot product * @param *pSrcA points to the first input vector * @param *pSrcB points to the second input vector * @param numSamples number of complex samples in each vector * @param *realResult real part of the result returned here * @param *imagResult imaginary part of the result returned here * @return none. */ void arm_cmplx_dot_prod_f32( float32_t * pSrcA, float32_t * pSrcB, uint32_t numSamples, float32_t * realResult, float32_t * imagResult) { float32_t real_sum = 0.0f, imag_sum = 0.0f; /* Temporary result storage */ #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) { /* CReal = A[0]* B[0] + A[2]* B[2] + A[4]* B[4] + .....+ A[numSamples-2]* B[numSamples-2] */ real_sum += (*pSrcA++) * (*pSrcB++); /* CImag = A[1]* B[1] + A[3]* B[3] + A[5]* B[5] + .....+ A[numSamples-1]* B[numSamples-1] */ imag_sum += (*pSrcA++) * (*pSrcB++); real_sum += (*pSrcA++) * (*pSrcB++); imag_sum += (*pSrcA++) * (*pSrcB++); real_sum += (*pSrcA++) * (*pSrcB++); imag_sum += (*pSrcA++) * (*pSrcB++); real_sum += (*pSrcA++) * (*pSrcB++); imag_sum += (*pSrcA++) * (*pSrcB++); /* 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) { /* CReal = A[0]* B[0] + A[2]* B[2] + A[4]* B[4] + .....+ A[numSamples-2]* B[numSamples-2] */ real_sum += (*pSrcA++) * (*pSrcB++); /* CImag = A[1]* B[1] + A[3]* B[3] + A[5]* B[5] + .....+ A[numSamples-1]* B[numSamples-1] */ imag_sum += (*pSrcA++) * (*pSrcB++); /* Decrement the loop counter */ blkCnt--; } #else /* Run the below code for Cortex-M0 */ while(numSamples > 0u) { /* CReal = A[0]* B[0] + A[2]* B[2] + A[4]* B[4] + .....+ A[numSamples-2]* B[numSamples-2] */ real_sum += (*pSrcA++) * (*pSrcB++); /* CImag = A[1]* B[1] + A[3]* B[3] + A[5]* B[5] + .....+ A[numSamples-1]* B[numSamples-1] */ imag_sum += (*pSrcA++) * (*pSrcB++); /* Decrement the loop counter */ numSamples--; } #endif /* #ifndef ARM_MATH_CM0 */ /* Store the real and imaginary results in the destination buffers */ *realResult = real_sum; *imagResult = imag_sum; } /** * @} end of cmplx_dot_prod group */