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Diff: cmsis_dsp/ComplexMathFunctions/arm_cmplx_mag_f32.c
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cmsis_dsp/ComplexMathFunctions/arm_cmplx_mag_f32.c Wed Nov 28 12:30:09 2012 +0000 @@ -0,0 +1,157 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_cmplx_mag_f32.c +* +* Description: Floating-point complex magnitude. +* +* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 +* +* Version 1.1.0 2012/02/15 +* Updated with more optimizations, bug fixes and minor API changes. +* +* Version 1.0.10 2011/7/15 +* Big Endian support added and Merged M0 and M3/M4 Source code. +* +* 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) +{ + float32_t realIn, imagIn; /* Temporary variables to hold input values */ + +#ifndef ARM_MATH_CM0 + + /* Run the below code for Cortex-M4 and Cortex-M3 */ + uint32_t blkCnt; /* loop counter */ + + /*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--; + } + +#else + + /* Run the below code for Cortex-M0 */ + + while(numSamples > 0u) + { + /* out = sqrt((real * real) + (imag * imag)) */ + realIn = *pSrc++; + imagIn = *pSrc++; + /* store the result in the destination buffer. */ + arm_sqrt_f32((realIn * realIn) + (imagIn * imagIn), pDst++); + + /* Decrement the loop counter */ + numSamples--; + } + +#endif /* #ifndef ARM_MATH_CM0 */ + +} + +/** + * @} end of cmplx_mag group + */