/* ----------------------------------------------------------------------
* Project: CMSIS DSP Library
* Title: arm_mat_scale_f32.c
* Description: Multiplies a floating-point matrix by a scalar
*
* $Date: 18. March 2019
* $Revision: V1.6.0
*
* Target Processor: Cortex-M cores
* -------------------------------------------------------------------- */
/*
* Copyright (C) 2010-2019 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 groupMatrix
*/
/**
@defgroup MatrixScale Matrix Scale
Multiplies a matrix by a scalar. This is accomplished by multiplying each element in the
matrix by the scalar. For example:
\image html MatrixScale.gif "Matrix Scaling of a 3 x 3 matrix"
The function checks to make sure that the input and output matrices are of the same size.
In the fixed-point Q15 and Q31 functions, <code>scale</code> is represented by
a fractional multiplication <code>scaleFract</code> and an arithmetic shift <code>shift</code>.
The shift allows the gain of the scaling operation to exceed 1.0.
The overall scale factor applied to the fixed-point data is
<pre>
scale = scaleFract * 2^shift.
</pre>
*/
/**
@addtogroup MatrixScale
@{
*/
/**
@brief Floating-point matrix scaling.
@param[in] pSrc points to input matrix
@param[in] scale scale factor to be applied
@param[out] pDst points to output matrix structure
@return execution status
- \ref ARM_MATH_SUCCESS : Operation successful
- \ref ARM_MATH_SIZE_MISMATCH : Matrix size check failed
*/
#if defined(ARM_MATH_NEON_EXPERIMENTAL)
arm_status arm_mat_scale_f32(
const arm_matrix_instance_f32 * pSrc,
float32_t scale,
arm_matrix_instance_f32 * pDst)
{
float32_t *pIn = pSrc->pData; /* input data matrix pointer */
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 scaling */
float32_t in1, in2, in3, in4; /* temporary variables */
float32_t out1, out2, out3, out4; /* temporary variables */
#ifdef ARM_MATH_MATRIX_CHECK
/* Check for matrix mismatch condition */
if ((pSrc->numRows != pDst->numRows) || (pSrc->numCols != pDst->numCols))
{
/* Set status as ARM_MATH_SIZE_MISMATCH */
status = ARM_MATH_SIZE_MISMATCH;
}
else
#endif /* #ifdef ARM_MATH_MATRIX_CHECK */
{
float32x4_t vec1;
float32x4_t res;
/* Total number of samples in the input matrix */
numSamples = (uint32_t) pSrc->numRows * pSrc->numCols;
blkCnt = numSamples >> 2;
/* 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) * scale */
/* Scaling and results are stored in the destination buffer. */
vec1 = vld1q_f32(pIn);
res = vmulq_f32(vec1, vdupq_n_f32(scale));
vst1q_f32(pOut, res);
/* update pointers to process next sampels */
pIn += 4U;
pOut += 4U;
/* Decrement the numSamples 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) * scale */
/* The results are stored in the destination buffer. */
*pOut++ = (*pIn++) * scale;
/* Decrement the loop counter */
blkCnt--;
}
/* Set status as ARM_MATH_SUCCESS */
status = ARM_MATH_SUCCESS;
}
/* Return to application */
return (status);
}
#else
arm_status arm_mat_scale_f32(
const arm_matrix_instance_f32 * pSrc,
float32_t scale,
arm_matrix_instance_f32 * pDst)
{
float32_t *pIn = pSrc->pData; /* Input data matrix pointer */
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 scaling */
#ifdef ARM_MATH_MATRIX_CHECK
/* Check for matrix mismatch condition */
if ((pSrc->numRows != pDst->numRows) ||
(pSrc->numCols != pDst->numCols) )
{
/* Set status as ARM_MATH_SIZE_MISMATCH */
status = ARM_MATH_SIZE_MISMATCH;
}
else
#endif /* #ifdef ARM_MATH_MATRIX_CHECK */
{
/* Total number of samples in input matrix */
numSamples = (uint32_t) pSrc->numRows * pSrc->numCols;
#if defined (ARM_MATH_LOOPUNROLL)
/* Loop unrolling: Compute 4 outputs at a time */
blkCnt = numSamples >> 2U;
while (blkCnt > 0U)
{
/* C(m,n) = A(m,n) * scale */
/* Scale and store result in destination buffer. */
*pOut++ = (*pIn++) * scale;
*pOut++ = (*pIn++) * scale;
*pOut++ = (*pIn++) * scale;
*pOut++ = (*pIn++) * scale;
/* Decrement loop counter */
blkCnt--;
}
/* Loop unrolling: Compute remaining outputs */
blkCnt = numSamples % 0x4U;
#else
/* Initialize blkCnt with number of samples */
blkCnt = numSamples;
#endif /* #if defined (ARM_MATH_LOOPUNROLL) */
while (blkCnt > 0U)
{
/* C(m,n) = A(m,n) * scale */
/* Scale and store result in destination buffer. */
*pOut++ = (*pIn++) * scale;
/* Decrement loop counter */
blkCnt--;
}
/* Set status as ARM_MATH_SUCCESS */
status = ARM_MATH_SUCCESS;
}
/* Return to application */
return (status);
}
#endif /* #if defined(ARM_MATH_NEON) */
/**
@} end of MatrixScale group
*/
