/* ---------------------------------------------------------------------- * Copyright (C) 2010 ARM Limited. All rights reserved. * * $Date: 29. November 2010 * $Revision: V1.0.3 * * Project: CMSIS DSP Library * Title: arm_abs_f32.c * * Description: Vector absolute value. * * Target Processor: Cortex-M4/Cortex-M3 * * 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. * * Version 0.0.7 2010/06/10 * Misra-C changes done * ---------------------------------------------------------------------------- */ #include "arm_math.h" #include /** * @ingroup groupMath */ /** * @defgroup BasicAbs Vector Absolute Value * * Computes the absolute value of a vector on an element-by-element basis. * *
  
 *     pDst[n] = abs(pSrcA[n]),   0 <= n < blockSize.  
 * 
* * The operation can be done in-place by setting the input and output pointers to the same buffer. * There are separate functions for floating-point, Q7, Q15, and Q31 data types. */ /** * @addtogroup BasicAbs * @{ */ /** * @brief Floating-point vector absolute value. * @param[in] *pSrc points to the input buffer * @param[out] *pDst points to the output buffer * @param[in] blockSize number of samples in each vector * @return none. */ void arm_abs_f32( float32_t * pSrc, float32_t * pDst, uint32_t blockSize) { uint32_t blkCnt; /* loop counter */ /*loop Unrolling */ blkCnt = blockSize >> 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 = |A| */ /* Calculate absolute and then store the results in the destination buffer. */ *pDst++ = fabsf(*pSrc++); *pDst++ = fabsf(*pSrc++); *pDst++ = fabsf(*pSrc++); *pDst++ = fabsf(*pSrc++); /* Decrement the loop counter */ blkCnt--; } /* If the blockSize is not a multiple of 4, compute any remaining output samples here. ** No loop unrolling is used. */ blkCnt = blockSize % 0x4u; while(blkCnt > 0u) { /* C = |A| */ /* Calculate absolute and then store the results in the destination buffer. */ *pDst++ = fabsf(*pSrc++); /* Decrement the loop counter */ blkCnt--; } } /** * @} end of BasicAbs group */