/* ---------------------------------------------------------------------- * Project: CMSIS DSP Library * Title: arm_cmplx_mag_f32.c * Description: Floating-point complex magnitude * * $Date: 27. January 2017 * $Revision: V.1.5.1 * * Target Processor: Cortex-M cores * -------------------------------------------------------------------- */ /* * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved. * * SPDX-License-Identifier: Apache-2.0 * * Licensed under the Apache License, Version 2.0 (the License); you may * not use this file except in compliance with the License. * You may obtain a copy of the License at * * www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an AS IS BASIS, WITHOUT * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ #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 */ #if defined (ARM_MATH_DSP) /* 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 /* #if defined (ARM_MATH_DSP) */ } /** * @} end of cmplx_mag group */