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Diff: cmsis_dsp/MatrixFunctions/arm_mat_scale_f32.c
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diff -r 83d0537c7d84 -r fdd22bb7aa52 cmsis_dsp/MatrixFunctions/arm_mat_scale_f32.c --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/cmsis_dsp/MatrixFunctions/arm_mat_scale_f32.c Wed Nov 28 12:30:09 2012 +0000 @@ -0,0 +1,179 @@ +/* ---------------------------------------------------------------------- +* Copyright (C) 2010 ARM Limited. All rights reserved. +* +* $Date: 15. February 2012 +* $Revision: V1.1.0 +* +* Project: CMSIS DSP Library +* Title: arm_mat_scale_f32.c +* +* Description: Multiplies a floating-point matrix by a scalar. +* +* 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. +* +* 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 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 structure + * @param[in] scale scale factor to be applied + * @param[out] *pDst points to output matrix structure + * @return The function returns either <code>ARM_MATH_SIZE_MISMATCH</code> + * or <code>ARM_MATH_SUCCESS</code> based on the outcome of size checking. + * + */ + +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 */ + +#ifndef ARM_MATH_CM0 + + float32_t in1, in2, in3, in4; /* temporary variables */ + float32_t out1, out2, out3, out4; /* temporary variables */ + +#endif // #ifndef ARM_MATH_CM0 + +#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 the input matrix */ + numSamples = (uint32_t) pSrc->numRows * pSrc->numCols; + +#ifndef ARM_MATH_CM0 + + /* Run the below code for Cortex-M4 and Cortex-M3 */ + + /* Loop Unrolling */ + blkCnt = numSamples >> 2; + + /* 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) * scale */ + /* Scaling and results are stored in the destination buffer. */ + in1 = pIn[0]; + in2 = pIn[1]; + in3 = pIn[2]; + in4 = pIn[3]; + + out1 = in1 * scale; + out2 = in2 * scale; + out3 = in3 * scale; + out4 = in4 * scale; + + + pOut[0] = out1; + pOut[1] = out2; + pOut[2] = out3; + pOut[3] = out4; + + /* 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; + +#else + + /* Run the below code for Cortex-M0 */ + + /* Initialize blkCnt with number of samples */ + blkCnt = numSamples; + +#endif /* #ifndef ARM_MATH_CM0 */ + + 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); +} + +/** + * @} end of MatrixScale group + */