Laxmi Kant Tiwari / mbed-dsp

CMSIS DSP Lib

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cmsis_dsp/ComplexMathFunctions/arm_cmplx_mag_f32.c@1:fdd22bb7aa52, 2012-11-28 (annotated)

Committer:
emilmont
Date:
Wed Nov 28 12:30:09 2012 +0000
Revision:
1:fdd22bb7aa52
Child:
2:da51fb522205
DSP library code

Who changed what in which revision?

UserRevisionLine numberNew contents of line
emilmont 1:fdd22bb7aa52 1 /* ----------------------------------------------------------------------
emilmont 1:fdd22bb7aa52 2 * Copyright (C) 2010 ARM Limited. All rights reserved.
emilmont 1:fdd22bb7aa52 3 *
emilmont 1:fdd22bb7aa52 4 * $Date: 15. February 2012
emilmont 1:fdd22bb7aa52 5 * $Revision: V1.1.0
emilmont 1:fdd22bb7aa52 6 *
emilmont 1:fdd22bb7aa52 7 * Project: CMSIS DSP Library
emilmont 1:fdd22bb7aa52 8 * Title: arm_cmplx_mag_f32.c
emilmont 1:fdd22bb7aa52 9 *
emilmont 1:fdd22bb7aa52 10 * Description: Floating-point complex magnitude.
emilmont 1:fdd22bb7aa52 11 *
emilmont 1:fdd22bb7aa52 12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
emilmont 1:fdd22bb7aa52 13 *
emilmont 1:fdd22bb7aa52 14 * Version 1.1.0 2012/02/15
emilmont 1:fdd22bb7aa52 15 * Updated with more optimizations, bug fixes and minor API changes.
emilmont 1:fdd22bb7aa52 16 *
emilmont 1:fdd22bb7aa52 17 * Version 1.0.10 2011/7/15
emilmont 1:fdd22bb7aa52 18 * Big Endian support added and Merged M0 and M3/M4 Source code.
emilmont 1:fdd22bb7aa52 19 *
emilmont 1:fdd22bb7aa52 20 * Version 1.0.3 2010/11/29
emilmont 1:fdd22bb7aa52 21 * Re-organized the CMSIS folders and updated documentation.
emilmont 1:fdd22bb7aa52 22 *
emilmont 1:fdd22bb7aa52 23 * Version 1.0.2 2010/11/11
emilmont 1:fdd22bb7aa52 24 * Documentation updated.
emilmont 1:fdd22bb7aa52 25 *
emilmont 1:fdd22bb7aa52 26 * Version 1.0.1 2010/10/05
emilmont 1:fdd22bb7aa52 27 * Production release and review comments incorporated.
emilmont 1:fdd22bb7aa52 28 *
emilmont 1:fdd22bb7aa52 29 * Version 1.0.0 2010/09/20
emilmont 1:fdd22bb7aa52 30 * Production release and review comments incorporated.
emilmont 1:fdd22bb7aa52 31 * ---------------------------------------------------------------------------- */
emilmont 1:fdd22bb7aa52 32
emilmont 1:fdd22bb7aa52 33 #include "arm_math.h"
emilmont 1:fdd22bb7aa52 34
emilmont 1:fdd22bb7aa52 35 /**
emilmont 1:fdd22bb7aa52 36 * @ingroup groupCmplxMath
emilmont 1:fdd22bb7aa52 37 */
emilmont 1:fdd22bb7aa52 38
emilmont 1:fdd22bb7aa52 39 /**
emilmont 1:fdd22bb7aa52 40 * @defgroup cmplx_mag Complex Magnitude
emilmont 1:fdd22bb7aa52 41 *
emilmont 1:fdd22bb7aa52 42 * Computes the magnitude of the elements of a complex data vector.
emilmont 1:fdd22bb7aa52 43 *
emilmont 1:fdd22bb7aa52 44 * The <code>pSrc</code> points to the source data and
emilmont 1:fdd22bb7aa52 45 * <code>pDst</code> points to the where the result should be written.
emilmont 1:fdd22bb7aa52 46 * <code>numSamples</code> specifies the number of complex samples
emilmont 1:fdd22bb7aa52 47 * in the input array and the data is stored in an interleaved fashion
emilmont 1:fdd22bb7aa52 48 * (real, imag, real, imag, ...).
emilmont 1:fdd22bb7aa52 49 * The input array has a total of <code>2*numSamples</code> values;
emilmont 1:fdd22bb7aa52 50 * the output array has a total of <code>numSamples</code> values.
emilmont 1:fdd22bb7aa52 51 * The underlying algorithm is used:
emilmont 1:fdd22bb7aa52 52 *
emilmont 1:fdd22bb7aa52 53 * <pre>
emilmont 1:fdd22bb7aa52 54 * for(n=0; n<numSamples; n++) {
emilmont 1:fdd22bb7aa52 55 * pDst[n] = sqrt(pSrc[(2*n)+0]^2 + pSrc[(2*n)+1]^2);
emilmont 1:fdd22bb7aa52 56 * }
emilmont 1:fdd22bb7aa52 57 * </pre>
emilmont 1:fdd22bb7aa52 58 *
emilmont 1:fdd22bb7aa52 59 * There are separate functions for floating-point, Q15, and Q31 data types.
emilmont 1:fdd22bb7aa52 60 */
emilmont 1:fdd22bb7aa52 61
emilmont 1:fdd22bb7aa52 62 /**
emilmont 1:fdd22bb7aa52 63 * @addtogroup cmplx_mag
emilmont 1:fdd22bb7aa52 64 * @{
emilmont 1:fdd22bb7aa52 65 */
emilmont 1:fdd22bb7aa52 66 /**
emilmont 1:fdd22bb7aa52 67 * @brief Floating-point complex magnitude.
emilmont 1:fdd22bb7aa52 68 * @param[in] *pSrc points to complex input buffer
emilmont 1:fdd22bb7aa52 69 * @param[out] *pDst points to real output buffer
emilmont 1:fdd22bb7aa52 70 * @param[in] numSamples number of complex samples in the input vector
emilmont 1:fdd22bb7aa52 71 * @return none.
emilmont 1:fdd22bb7aa52 72 *
emilmont 1:fdd22bb7aa52 73 */
emilmont 1:fdd22bb7aa52 74
emilmont 1:fdd22bb7aa52 75
emilmont 1:fdd22bb7aa52 76 void arm_cmplx_mag_f32(
emilmont 1:fdd22bb7aa52 77 float32_t * pSrc,
emilmont 1:fdd22bb7aa52 78 float32_t * pDst,
emilmont 1:fdd22bb7aa52 79 uint32_t numSamples)
emilmont 1:fdd22bb7aa52 80 {
emilmont 1:fdd22bb7aa52 81 float32_t realIn, imagIn; /* Temporary variables to hold input values */
emilmont 1:fdd22bb7aa52 82
emilmont 1:fdd22bb7aa52 83 #ifndef ARM_MATH_CM0
emilmont 1:fdd22bb7aa52 84
emilmont 1:fdd22bb7aa52 85 /* Run the below code for Cortex-M4 and Cortex-M3 */
emilmont 1:fdd22bb7aa52 86 uint32_t blkCnt; /* loop counter */
emilmont 1:fdd22bb7aa52 87
emilmont 1:fdd22bb7aa52 88 /*loop Unrolling */
emilmont 1:fdd22bb7aa52 89 blkCnt = numSamples >> 2u;
emilmont 1:fdd22bb7aa52 90
emilmont 1:fdd22bb7aa52 91 /* First part of the processing with loop unrolling. Compute 4 outputs at a time.
emilmont 1:fdd22bb7aa52 92 ** a second loop below computes the remaining 1 to 3 samples. */
emilmont 1:fdd22bb7aa52 93 while(blkCnt > 0u)
emilmont 1:fdd22bb7aa52 94 {
emilmont 1:fdd22bb7aa52 95
emilmont 1:fdd22bb7aa52 96 /* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
emilmont 1:fdd22bb7aa52 97 realIn = *pSrc++;
emilmont 1:fdd22bb7aa52 98 imagIn = *pSrc++;
emilmont 1:fdd22bb7aa52 99 /* store the result in the destination buffer. */
emilmont 1:fdd22bb7aa52 100 arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);
emilmont 1:fdd22bb7aa52 101
emilmont 1:fdd22bb7aa52 102 realIn = *pSrc++;
emilmont 1:fdd22bb7aa52 103 imagIn = *pSrc++;
emilmont 1:fdd22bb7aa52 104 arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);
emilmont 1:fdd22bb7aa52 105
emilmont 1:fdd22bb7aa52 106 realIn = *pSrc++;
emilmont 1:fdd22bb7aa52 107 imagIn = *pSrc++;
emilmont 1:fdd22bb7aa52 108 arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);
emilmont 1:fdd22bb7aa52 109
emilmont 1:fdd22bb7aa52 110 realIn = *pSrc++;
emilmont 1:fdd22bb7aa52 111 imagIn = *pSrc++;
emilmont 1:fdd22bb7aa52 112 arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);
emilmont 1:fdd22bb7aa52 113
emilmont 1:fdd22bb7aa52 114
emilmont 1:fdd22bb7aa52 115 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 116 blkCnt--;
emilmont 1:fdd22bb7aa52 117 }
emilmont 1:fdd22bb7aa52 118
emilmont 1:fdd22bb7aa52 119 /* If the numSamples is not a multiple of 4, compute any remaining output samples here.
emilmont 1:fdd22bb7aa52 120 ** No loop unrolling is used. */
emilmont 1:fdd22bb7aa52 121 blkCnt = numSamples % 0x4u;
emilmont 1:fdd22bb7aa52 122
emilmont 1:fdd22bb7aa52 123 while(blkCnt > 0u)
emilmont 1:fdd22bb7aa52 124 {
emilmont 1:fdd22bb7aa52 125 /* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */
emilmont 1:fdd22bb7aa52 126 realIn = *pSrc++;
emilmont 1:fdd22bb7aa52 127 imagIn = *pSrc++;
emilmont 1:fdd22bb7aa52 128 /* store the result in the destination buffer. */
emilmont 1:fdd22bb7aa52 129 arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);
emilmont 1:fdd22bb7aa52 130
emilmont 1:fdd22bb7aa52 131 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 132 blkCnt--;
emilmont 1:fdd22bb7aa52 133 }
emilmont 1:fdd22bb7aa52 134
emilmont 1:fdd22bb7aa52 135 #else
emilmont 1:fdd22bb7aa52 136
emilmont 1:fdd22bb7aa52 137 /* Run the below code for Cortex-M0 */
emilmont 1:fdd22bb7aa52 138
emilmont 1:fdd22bb7aa52 139 while(numSamples > 0u)
emilmont 1:fdd22bb7aa52 140 {
emilmont 1:fdd22bb7aa52 141 /* out = sqrt((real * real) + (imag * imag)) */
emilmont 1:fdd22bb7aa52 142 realIn = *pSrc++;
emilmont 1:fdd22bb7aa52 143 imagIn = *pSrc++;
emilmont 1:fdd22bb7aa52 144 /* store the result in the destination buffer. */
emilmont 1:fdd22bb7aa52 145 arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++);
emilmont 1:fdd22bb7aa52 146
emilmont 1:fdd22bb7aa52 147 /* Decrement the loop counter */
emilmont 1:fdd22bb7aa52 148 numSamples--;
emilmont 1:fdd22bb7aa52 149 }
emilmont 1:fdd22bb7aa52 150
emilmont 1:fdd22bb7aa52 151 #endif /* #ifndef ARM_MATH_CM0 */
emilmont 1:fdd22bb7aa52 152
emilmont 1:fdd22bb7aa52 153 }
emilmont 1:fdd22bb7aa52 154
emilmont 1:fdd22bb7aa52 155 /**
emilmont 1:fdd22bb7aa52 156 * @} end of cmplx_mag group
emilmont 1:fdd22bb7aa52 157 */