dsp - CMSIS DSP Library from CMSIS 2.0. See http://www.…

Users » simon » Code » dsp

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/ComplexMathFunctions/arm_cmplx_mag_squared_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_cmplx_mag_squared_f32.c
simon	0:1014af42efd9	9	*
simon	0:1014af42efd9	10	* Description: Floating-point complex magnitude squared.
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
simon	0:1014af42efd9	27	#include "arm_math.h"
simon	0:1014af42efd9	28
simon	0:1014af42efd9	29	/**
simon	0:1014af42efd9	30	* @ingroup groupCmplxMath
simon	0:1014af42efd9	31	*/
simon	0:1014af42efd9	32
simon	0:1014af42efd9	33	/**
simon	0:1014af42efd9	34	* @defgroup cmplx_mag_squared Complex Magnitude Squared
simon	0:1014af42efd9	35	*
simon	0:1014af42efd9	36	* Computes the magnitude squared of the elements of a complex data vector.
simon	0:1014af42efd9	37	*
simon	0:1014af42efd9	38	* The <code>pSrc</code> points to the source data and
simon	0:1014af42efd9	39	* <code>pDst</code> points to the where the result should be written.
simon	0:1014af42efd9	40	* <code>numSamples</code> specifies the number of complex samples
simon	0:1014af42efd9	41	* in the input array and the data is stored in an interleaved fashion
simon	0:1014af42efd9	42	* (real, imag, real, imag, ...).
simon	0:1014af42efd9	43	* The input array has a total of <code>2*numSamples</code> values;
simon	0:1014af42efd9	44	* the output array has a total of <code>numSamples</code> values.
simon	0:1014af42efd9	45	*
simon	0:1014af42efd9	46	* The underlying algorithm is used:
simon	0:1014af42efd9	47	*
simon	0:1014af42efd9	48	* <pre>
simon	0:1014af42efd9	49	* for(n=0; n<numSamples; n++) {
simon	0:1014af42efd9	50	* pDst[n] = pSrc[(2n)+0]^2 + pSrc[(2n)+1]^2;
simon	0:1014af42efd9	51	* }
simon	0:1014af42efd9	52	* </pre>
simon	0:1014af42efd9	53	*
simon	0:1014af42efd9	54	* There are separate functions for floating-point, Q15, and Q31 data types.
simon	0:1014af42efd9	55	*/
simon	0:1014af42efd9	56
simon	0:1014af42efd9	57	/**
simon	0:1014af42efd9	58	* @addtogroup cmplx_mag_squared
simon	0:1014af42efd9	59	* @{
simon	0:1014af42efd9	60	*/
simon	0:1014af42efd9	61
simon	0:1014af42efd9	62
simon	0:1014af42efd9	63	/**
simon	0:1014af42efd9	64	* @brief Floating-point complex magnitude squared
simon	0:1014af42efd9	65	* @param[in] *pSrc points to the complex input vector
simon	0:1014af42efd9	66	* @param[out] *pDst points to the real output vector
simon	0:1014af42efd9	67	* @param[in] numSamples number of complex samples in the input vector
simon	0:1014af42efd9	68	* @return none.
simon	0:1014af42efd9	69	*/
simon	0:1014af42efd9	70
simon	0:1014af42efd9	71	void arm_cmplx_mag_squared_f32(
simon	0:1014af42efd9	72	float32_t * pSrc,
simon	0:1014af42efd9	73	float32_t * pDst,
simon	0:1014af42efd9	74	uint32_t numSamples)
simon	0:1014af42efd9	75	{
simon	0:1014af42efd9	76	float32_t real, imag; /* Temporary variables to store real and imaginary values */
simon	0:1014af42efd9	77	uint32_t blkCnt; /* loop counter */
simon	0:1014af42efd9	78
simon	0:1014af42efd9	79	/loop Unrolling /
simon	0:1014af42efd9	80	blkCnt = numSamples >> 2u;
simon	0:1014af42efd9	81
simon	0:1014af42efd9	82	/* First part of the processing with loop unrolling. Compute 4 outputs at a time.
simon	0:1014af42efd9	83	** a second loop below computes the remaining 1 to 3 samples. */
simon	0:1014af42efd9	84	while(blkCnt > 0u)
simon	0:1014af42efd9	85	{
simon	0:1014af42efd9	86	/* C[0] = (A[0] * A[0] + A[1] * A[1]) */
simon	0:1014af42efd9	87	real = *pSrc++;
simon	0:1014af42efd9	88	imag = *pSrc++;
simon	0:1014af42efd9	89	/* store the result in the destination buffer. */
simon	0:1014af42efd9	90	pDst++ = (real real) + (imag * imag);
simon	0:1014af42efd9	91
simon	0:1014af42efd9	92	real = *pSrc++;
simon	0:1014af42efd9	93	imag = *pSrc++;
simon	0:1014af42efd9	94	pDst++ = (real real) + (imag * imag);
simon	0:1014af42efd9	95
simon	0:1014af42efd9	96	real = *pSrc++;
simon	0:1014af42efd9	97	imag = *pSrc++;
simon	0:1014af42efd9	98	pDst++ = (real real) + (imag * imag);
simon	0:1014af42efd9	99
simon	0:1014af42efd9	100	real = *pSrc++;
simon	0:1014af42efd9	101	imag = *pSrc++;
simon	0:1014af42efd9	102	pDst++ = (real real) + (imag * imag);
simon	0:1014af42efd9	103
simon	0:1014af42efd9	104	/* Decrement the loop counter */
simon	0:1014af42efd9	105	blkCnt--;
simon	0:1014af42efd9	106	}
simon	0:1014af42efd9	107
simon	0:1014af42efd9	108	/* If the numSamples is not a multiple of 4, compute any remaining output samples here.
simon	0:1014af42efd9	109	** No loop unrolling is used. */
simon	0:1014af42efd9	110	blkCnt = numSamples % 0x4u;
simon	0:1014af42efd9	111
simon	0:1014af42efd9	112	while(blkCnt > 0u)
simon	0:1014af42efd9	113	{
simon	0:1014af42efd9	114	/* C[0] = (A[0] * A[0] + A[1] * A[1]) */
simon	0:1014af42efd9	115	real = *pSrc++;
simon	0:1014af42efd9	116	imag = *pSrc++;
simon	0:1014af42efd9	117	/* store the result in the destination buffer. */
simon	0:1014af42efd9	118	pDst++ = (real real) + (imag * imag);
simon	0:1014af42efd9	119
simon	0:1014af42efd9	120	/* Decrement the loop counter */
simon	0:1014af42efd9	121	blkCnt--;
simon	0:1014af42efd9	122	}
simon	0:1014af42efd9	123	}
simon	0:1014af42efd9	124
simon	0:1014af42efd9	125	/**
simon	0:1014af42efd9	126	* @} end of cmplx_mag_squared group
simon	0:1014af42efd9	127	*/

Repository toolbox

Export to desktop IDE

Repository details

Type:	Library
Created:	10 Mar 2011
Imports:	907
Forks:	1
Commits:	3
Dependents:	5
Dependencies:	0
Followers:	35

src/Cortex-M4-M3/ComplexMathFunctions/arm_cmplx_mag_squared_f32.c@0:1014af42efd9, 2011-03-10 (annotated)

Who changed what in which revision?

Repository toolbox

Repository details

Important Information for this Arm website

Access Warning