/* ----------------------------------------------------------------------
* Copyright (C) 2010 ARM Limited. All rights reserved.
*
* $Date: 29. November 2010
* $Revision: V1.0.3
*
* Project: CMSIS DSP Library
* Title: arm_mat_sub_f32.c
*
* Description: Floating-point matrix subtraction.
*
* 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.
*
* Version 0.0.5 2010/04/26
* incorporated review comments and updated with latest CMSIS layer
*
* Version 0.0.3 2010/03/10
* Initial version
* -------------------------------------------------------------------- */
#include "arm_math.h"
/**
* @ingroup groupMatrix
*/
/**
* @defgroup MatrixSub Matrix Subtraction
*
* Subtract two matrices.
* \image html MatrixSubtraction.gif "Subraction of two 3 x 3 matrices"
*
* The functions check to make sure that
* pSrcA
, pSrcB
, and pDst
have the same
* number of rows and columns.
*/
/**
* @addtogroup MatrixSub
* @{
*/
/**
* @brief Floating-point matrix subtraction
* @param[in] *pSrcA points to the first input matrix structure
* @param[in] *pSrcB points to the second input matrix structure
* @param[out] *pDst points to output matrix structure
* @return The function returns either
* ARM_MATH_SIZE_MISMATCH
or ARM_MATH_SUCCESS
based on the outcome of size checking.
*/
arm_status arm_mat_sub_f32(
const arm_matrix_instance_f32 * pSrcA,
const arm_matrix_instance_f32 * pSrcB,
arm_matrix_instance_f32 * pDst)
{
float32_t *pIn1 = pSrcA->pData; /* input data matrix pointer A */
float32_t *pIn2 = pSrcB->pData; /* input data matrix pointer B */
float32_t *pOut = pDst->pData; /* output data matrix pointer */
uint32_t numSamples; /* total number of elements in the matrix */
uint32_t blkCnt; /* loop counters */
arm_status status; /* status of matrix subtraction */
#ifdef ARM_MATH_MATRIX_CHECK
/* Check for matrix mismatch condition */
if((pSrcA->numRows != pSrcB->numRows) ||
(pSrcA->numCols != pSrcB->numCols) ||
(pSrcA->numRows != pDst->numRows) || (pSrcA->numCols != pDst->numCols))
{
/* Set status as ARM_MATH_SIZE_MISMATCH */
status = ARM_MATH_SIZE_MISMATCH;
}
else
#endif
{
/* Total number of samples in the input matrix */
numSamples = (uint32_t) pSrcA->numRows * pSrcA->numCols;
/* 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(m,n) = A(m,n) - B(m,n) */
/* Subtract and then store the results in the destination buffer. */
*pOut++ = (*pIn1++) - (*pIn2++);
*pOut++ = (*pIn1++) - (*pIn2++);
*pOut++ = (*pIn1++) - (*pIn2++);
*pOut++ = (*pIn1++) - (*pIn2++);
/* 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(m,n) = A(m,n) - B(m,n) */
/* Subtract and then store the results in the destination buffer. */
*pOut++ = (*pIn1++) - (*pIn2++);
/* Decrement the loop counter */
blkCnt--;
}
/* Set status as ARM_MATH_SUCCESS */
status = ARM_MATH_SUCCESS;
}
/* Return to application */
return (status);
}
/**
* @} end of MatrixSub group
*/