/* ---------------------------------------------------------------------- * Copyright (C) 2010 ARM Limited. All rights reserved. * * $Date: 15. July 2011 * $Revision: V1.0.10 * * Project: CMSIS DSP Library * Title: arm_cmplx_mag_squared_f32.c * * Description: Floating-point complex magnitude squared. * * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 * * 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_squared Complex Magnitude Squared * * Computes the magnitude squared of the elements of a complex data vector. * * The pSrc points to the source data and * pDst points to the where the result should be written. * numSamples 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 2*numSamples values; * the output array has a total of numSamples values. * * The underlying algorithm is used: * *
   
 * for(n=0; n   
 *   
 * There are separate functions for floating-point, Q15, and Q31 data types.   
 */

/**   
 * @addtogroup cmplx_mag_squared   
 * @{   
 */


/**   
 * @brief  Floating-point complex magnitude squared   
 * @param[in]  *pSrc points to the complex input vector   
 * @param[out]  *pDst points to the real output vector   
 * @param[in]  numSamples number of complex samples in the input vector   
 * @return none.   
 */

void arm_cmplx_mag_squared_f32(
  float32_t * pSrc,
  float32_t * pDst,
  uint32_t numSamples)
{
  float32_t real, imag;                          /* Temporary variables to store real and imaginary 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] = (A[0] * A[0] + A[1] * A[1]) */
    real = *pSrc++;
    imag = *pSrc++;
    /* store the result in the destination buffer. */
    *pDst++ = (real * real) + (imag * imag);

    real = *pSrc++;
    imag = *pSrc++;
    *pDst++ = (real * real) + (imag * imag);

    real = *pSrc++;
    imag = *pSrc++;
    *pDst++ = (real * real) + (imag * imag);

    real = *pSrc++;
    imag = *pSrc++;
    *pDst++ = (real * real) + (imag * imag);

    /* 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] = (A[0] * A[0] + A[1] * A[1]) */
    real = *pSrc++;
    imag = *pSrc++;
    /* store the result in the destination buffer. */
    *pDst++ = (real * real) + (imag * imag);

    /* Decrement the loop counter */
    blkCnt--;
  }

#else

  /* Run the below code for Cortex-M0 */

  while(numSamples > 0u)
  {
    /* reading real and imaginary values */
    real = *pSrc++;
    imag = *pSrc++;

    /* out = (real * real) + (imag * imag) */
    /* store the result in the destination buffer. */
    *pDst++ = (real * real) + (imag * imag);

    /* Decrement the loop counter */
    numSamples--;
  }

#endif /* #ifndef ARM_MATH_CM0 */

}

/**   
 * @} end of cmplx_mag_squared group   
 */