Simon Ford
CMSIS DSP Library from CMSIS 2.0. See http://www.onarm.com/cmsis/ for full details
Dependents: K22F_DSP_Matrix_least_square BNO055-ELEC3810 1BNO055 ECE4180Project--Slave2 ... more
src/Cortex-M4-M3/BasicMathFunctions/arm_abs_f32.c@0:1014af42efd9, 2011-03-10 (annotated)
- Committer:
- simon
- Date:
- Thu Mar 10 15:07:50 2011 +0000
- Revision:
- 0:1014af42efd9
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| simon | 0:1014af42efd9 | 1 | /* ---------------------------------------------------------------------- |
| simon | 0:1014af42efd9 | 2 | * Copyright (C) 2010 ARM Limited. All rights reserved. |
| simon | 0:1014af42efd9 | 3 | * |
| simon | 0:1014af42efd9 | 4 | * $Date: 29. November 2010 |
| simon | 0:1014af42efd9 | 5 | * $Revision: V1.0.3 |
| simon | 0:1014af42efd9 | 6 | * |
| simon | 0:1014af42efd9 | 7 | * Project: CMSIS DSP Library |
| simon | 0:1014af42efd9 | 8 | * Title: arm_abs_f32.c |
| simon | 0:1014af42efd9 | 9 | * |
| simon | 0:1014af42efd9 | 10 | * Description: Vector absolute value. |
| simon | 0:1014af42efd9 | 11 | * |
| simon | 0:1014af42efd9 | 12 | * Target Processor: Cortex-M4/Cortex-M3 |
| simon | 0:1014af42efd9 | 13 | * |
| simon | 0:1014af42efd9 | 14 | * Version 1.0.3 2010/11/29 |
| simon | 0:1014af42efd9 | 15 | * Re-organized the CMSIS folders and updated documentation. |
| simon | 0:1014af42efd9 | 16 | * |
| simon | 0:1014af42efd9 | 17 | * Version 1.0.2 2010/11/11 |
| simon | 0:1014af42efd9 | 18 | * Documentation updated. |
| simon | 0:1014af42efd9 | 19 | * |
| simon | 0:1014af42efd9 | 20 | * Version 1.0.1 2010/10/05 |
| simon | 0:1014af42efd9 | 21 | * Production release and review comments incorporated. |
| simon | 0:1014af42efd9 | 22 | * |
| simon | 0:1014af42efd9 | 23 | * Version 1.0.0 2010/09/20 |
| simon | 0:1014af42efd9 | 24 | * Production release and review comments incorporated. |
| simon | 0:1014af42efd9 | 25 | * |
| simon | 0:1014af42efd9 | 26 | * Version 0.0.7 2010/06/10 |
| simon | 0:1014af42efd9 | 27 | * Misra-C changes done |
| simon | 0:1014af42efd9 | 28 | * ---------------------------------------------------------------------------- */ |
| simon | 0:1014af42efd9 | 29 | |
| simon | 0:1014af42efd9 | 30 | #include "arm_math.h" |
| simon | 0:1014af42efd9 | 31 | #include <math.h> |
| simon | 0:1014af42efd9 | 32 | |
| simon | 0:1014af42efd9 | 33 | /** |
| simon | 0:1014af42efd9 | 34 | * @ingroup groupMath |
| simon | 0:1014af42efd9 | 35 | */ |
| simon | 0:1014af42efd9 | 36 | |
| simon | 0:1014af42efd9 | 37 | /** |
| simon | 0:1014af42efd9 | 38 | * @defgroup BasicAbs Vector Absolute Value |
| simon | 0:1014af42efd9 | 39 | * |
| simon | 0:1014af42efd9 | 40 | * Computes the absolute value of a vector on an element-by-element basis. |
| simon | 0:1014af42efd9 | 41 | * |
| simon | 0:1014af42efd9 | 42 | * <pre> |
| simon | 0:1014af42efd9 | 43 | * pDst[n] = abs(pSrcA[n]), 0 <= n < blockSize. |
| simon | 0:1014af42efd9 | 44 | * </pre> |
| simon | 0:1014af42efd9 | 45 | * |
| simon | 0:1014af42efd9 | 46 | * The operation can be done in-place by setting the input and output pointers to the same buffer. |
| simon | 0:1014af42efd9 | 47 | * There are separate functions for floating-point, Q7, Q15, and Q31 data types. |
| simon | 0:1014af42efd9 | 48 | */ |
| simon | 0:1014af42efd9 | 49 | |
| simon | 0:1014af42efd9 | 50 | /** |
| simon | 0:1014af42efd9 | 51 | * @addtogroup BasicAbs |
| simon | 0:1014af42efd9 | 52 | * @{ |
| simon | 0:1014af42efd9 | 53 | */ |
| simon | 0:1014af42efd9 | 54 | |
| simon | 0:1014af42efd9 | 55 | /** |
| simon | 0:1014af42efd9 | 56 | * @brief Floating-point vector absolute value. |
| simon | 0:1014af42efd9 | 57 | * @param[in] *pSrc points to the input buffer |
| simon | 0:1014af42efd9 | 58 | * @param[out] *pDst points to the output buffer |
| simon | 0:1014af42efd9 | 59 | * @param[in] blockSize number of samples in each vector |
| simon | 0:1014af42efd9 | 60 | * @return none. |
| simon | 0:1014af42efd9 | 61 | */ |
| simon | 0:1014af42efd9 | 62 | |
| simon | 0:1014af42efd9 | 63 | void arm_abs_f32( |
| simon | 0:1014af42efd9 | 64 | float32_t * pSrc, |
| simon | 0:1014af42efd9 | 65 | float32_t * pDst, |
| simon | 0:1014af42efd9 | 66 | uint32_t blockSize) |
| simon | 0:1014af42efd9 | 67 | { |
| simon | 0:1014af42efd9 | 68 | uint32_t blkCnt; /* loop counter */ |
| simon | 0:1014af42efd9 | 69 | |
| simon | 0:1014af42efd9 | 70 | /*loop Unrolling */ |
| simon | 0:1014af42efd9 | 71 | blkCnt = blockSize >> 2u; |
| simon | 0:1014af42efd9 | 72 | |
| simon | 0:1014af42efd9 | 73 | /* First part of the processing with loop unrolling. Compute 4 outputs at a time. |
| simon | 0:1014af42efd9 | 74 | ** a second loop below computes the remaining 1 to 3 samples. */ |
| simon | 0:1014af42efd9 | 75 | while(blkCnt > 0u) |
| simon | 0:1014af42efd9 | 76 | { |
| simon | 0:1014af42efd9 | 77 | /* C = |A| */ |
| simon | 0:1014af42efd9 | 78 | /* Calculate absolute and then store the results in the destination buffer. */ |
| simon | 0:1014af42efd9 | 79 | *pDst++ = fabsf(*pSrc++); |
| simon | 0:1014af42efd9 | 80 | *pDst++ = fabsf(*pSrc++); |
| simon | 0:1014af42efd9 | 81 | *pDst++ = fabsf(*pSrc++); |
| simon | 0:1014af42efd9 | 82 | *pDst++ = fabsf(*pSrc++); |
| simon | 0:1014af42efd9 | 83 | |
| simon | 0:1014af42efd9 | 84 | /* Decrement the loop counter */ |
| simon | 0:1014af42efd9 | 85 | blkCnt--; |
| simon | 0:1014af42efd9 | 86 | } |
| simon | 0:1014af42efd9 | 87 | |
| simon | 0:1014af42efd9 | 88 | /* If the blockSize is not a multiple of 4, compute any remaining output samples here. |
| simon | 0:1014af42efd9 | 89 | ** No loop unrolling is used. */ |
| simon | 0:1014af42efd9 | 90 | blkCnt = blockSize % 0x4u; |
| simon | 0:1014af42efd9 | 91 | |
| simon | 0:1014af42efd9 | 92 | while(blkCnt > 0u) |
| simon | 0:1014af42efd9 | 93 | { |
| simon | 0:1014af42efd9 | 94 | /* C = |A| */ |
| simon | 0:1014af42efd9 | 95 | /* Calculate absolute and then store the results in the destination buffer. */ |
| simon | 0:1014af42efd9 | 96 | *pDst++ = fabsf(*pSrc++); |
| simon | 0:1014af42efd9 | 97 | |
| simon | 0:1014af42efd9 | 98 | /* Decrement the loop counter */ |
| simon | 0:1014af42efd9 | 99 | blkCnt--; |
| simon | 0:1014af42efd9 | 100 | } |
| simon | 0:1014af42efd9 | 101 | } |
| simon | 0:1014af42efd9 | 102 | |
| simon | 0:1014af42efd9 | 103 | /** |
| simon | 0:1014af42efd9 | 104 | * @} end of BasicAbs group |
| simon | 0:1014af42efd9 | 105 | */ |