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_f32.c
- Committer:
- simon
- Date:
- 2011-03-10
- Revision:
- 0:1014af42efd9
File content as of revision 0:1014af42efd9:
/* ---------------------------------------------------------------------- * Copyright (C) 2010 ARM Limited. All rights reserved. * * $Date: 29. November 2010 * $Revision: V1.0.3 * * Project: CMSIS DSP Library * Title: arm_cmplx_mag_f32.c * * Description: Floating-point complex magnitude. * * 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. * ---------------------------------------------------------------------------- */ #include "arm_math.h" /** * @ingroup groupCmplxMath */ /** * @defgroup cmplx_mag Complex Magnitude * * Computes the magnitude of the elements of a complex data vector. * * The <code>pSrc</code> points to the source data and * <code>pDst</code> points to the where the result should be written. * <code>numSamples</code> specifies the number of complex samples * in the input array and the data is stored in an interleaved fashion * (real, imag, real, imag, ...). * The input array has a total of <code>2*numSamples</code> values; * the output array has a total of <code>numSamples</code> values. * The underlying algorithm is used: * * <pre> * for(n=0; n<numSamples; n++) { * pDst[n] = sqrt(pSrc[(2*n)+0]^2 + pSrc[(2*n)+1]^2); * } * </pre> * * There are separate functions for floating-point, Q15, and Q31 data types. */ /** * @addtogroup cmplx_mag * @{ */ /** * @brief Floating-point complex magnitude. * @param[in] *pSrc points to complex input buffer * @param[out] *pDst points to real output buffer * @param[in] numSamples number of complex samples in the input vector * @return none. * */ void arm_cmplx_mag_f32( float32_t * pSrc, float32_t * pDst, uint32_t numSamples) { uint32_t blkCnt; /* loop counter */ float32_t realIn, imagIn; /* Temporary variables to hold input values */ /*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) { /* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */ realIn = *pSrc++; imagIn = *pSrc++; /* store the result in the destination buffer. */ arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++); realIn = *pSrc++; imagIn = *pSrc++; arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++); realIn = *pSrc++; imagIn = *pSrc++; arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++); realIn = *pSrc++; imagIn = *pSrc++; arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++); /* 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) { /* C[0] = sqrt(A[0] * A[0] + A[1] * A[1]) */ realIn = *pSrc++; imagIn = *pSrc++; /* store the result in the destination buffer. */ arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++); /* Decrement the loop counter */ blkCnt--; } } /** * @} end of cmplx_mag group */