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/* ---------------------------------------------------------------------- |
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* Copyright (C) 2010-2014 ARM Limited. All rights reserved. |
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* |
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* $Date: 19. March 2015 |
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* $Revision: V.1.4.5 |
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* |
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* Project: CMSIS DSP Library |
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* Title: arm_mat_inverse_f64.c |
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* |
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* Description: Floating-point matrix inverse. |
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* |
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* Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 |
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* |
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* Redistribution and use in source and binary forms, with or without |
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* modification, are permitted provided that the following conditions |
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* are met: |
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* - Redistributions of source code must retain the above copyright |
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* notice, this list of conditions and the following disclaimer. |
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* - Redistributions in binary form must reproduce the above copyright |
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* notice, this list of conditions and the following disclaimer in |
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* the documentation and/or other materials provided with the |
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* distribution. |
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* - Neither the name of ARM LIMITED nor the names of its contributors |
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* may be used to endorse or promote products derived from this |
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* software without specific prior written permission. |
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* |
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* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
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* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
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* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
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* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
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* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
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* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
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* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
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* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
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* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN |
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* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
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* POSSIBILITY OF SUCH DAMAGE. |
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* -------------------------------------------------------------------- */ |
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#include "arm_math.h" |
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/** |
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* @ingroup groupMatrix |
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*/ |
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/** |
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* @defgroup MatrixInv Matrix Inverse |
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* |
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* Computes the inverse of a matrix. |
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* |
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* The inverse is defined only if the input matrix is square and non-singular (the determinant |
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* is non-zero). The function checks that the input and output matrices are square and of the |
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* same size. |
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* |
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* Matrix inversion is numerically sensitive and the CMSIS DSP library only supports matrix |
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* inversion of floating-point matrices. |
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* |
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* \par Algorithm |
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* The Gauss-Jordan method is used to find the inverse. |
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* The algorithm performs a sequence of elementary row-operations until it |
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* reduces the input matrix to an identity matrix. Applying the same sequence |
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* of elementary row-operations to an identity matrix yields the inverse matrix. |
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* If the input matrix is singular, then the algorithm terminates and returns error status |
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* <code>ARM_MATH_SINGULAR</code>. |
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* \image html MatrixInverse.gif "Matrix Inverse of a 3 x 3 matrix using Gauss-Jordan Method" |
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*/ |
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/** |
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* @addtogroup MatrixInv |
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* @{ |
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*/ |
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/** |
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* @brief Floating-point matrix inverse. |
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* @param[in] *pSrc points to input matrix structure |
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* @param[out] *pDst points to output matrix structure |
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* @return The function returns |
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* <code>ARM_MATH_SIZE_MISMATCH</code> if the input matrix is not square or if the size |
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* of the output matrix does not match the size of the input matrix. |
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* If the input matrix is found to be singular (non-invertible), then the function returns |
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* <code>ARM_MATH_SINGULAR</code>. Otherwise, the function returns <code>ARM_MATH_SUCCESS</code>. |
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*/ |
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arm_status arm_mat_inverse_f64( |
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const arm_matrix_instance_f64 * pSrc, |
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arm_matrix_instance_f64 * pDst) |
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{ |
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float64_t *pIn = pSrc->pData; /* input data matrix pointer */ |
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float64_t *pOut = pDst->pData; /* output data matrix pointer */ |
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float64_t *pInT1, *pInT2; /* Temporary input data matrix pointer */ |
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float64_t *pOutT1, *pOutT2; /* Temporary output data matrix pointer */ |
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float64_t *pPivotRowIn, *pPRT_in, *pPivotRowDst, *pPRT_pDst; /* Temporary input and output data matrix pointer */ |
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uint32_t numRows = pSrc->numRows; /* Number of rows in the matrix */ |
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uint32_t numCols = pSrc->numCols; /* Number of Cols in the matrix */ |
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#ifndef ARM_MATH_CM0_FAMILY |
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float64_t maxC; /* maximum value in the column */ |
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/* Run the below code for Cortex-M4 and Cortex-M3 */ |
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float64_t Xchg, in = 0.0f, in1; /* Temporary input values */ |
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uint32_t i, rowCnt, flag = 0u, j, loopCnt, k, l; /* loop counters */ |
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arm_status status; /* status of matrix inverse */ |
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#ifdef ARM_MATH_MATRIX_CHECK |
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/* Check for matrix mismatch condition */ |
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if((pSrc->numRows != pSrc->numCols) || (pDst->numRows != pDst->numCols) |
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|| (pSrc->numRows != pDst->numRows)) |
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{ |
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/* Set status as ARM_MATH_SIZE_MISMATCH */ |
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status = ARM_MATH_SIZE_MISMATCH; |
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} |
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else |
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#endif /* #ifdef ARM_MATH_MATRIX_CHECK */ |
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{ |
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/*-------------------------------------------------------------------------------------------------------------- |
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* Matrix Inverse can be solved using elementary row operations. |
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* |
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* Gauss-Jordan Method: |
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* |
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* 1. First combine the identity matrix and the input matrix separated by a bar to form an |
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* augmented matrix as follows: |
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* _ _ _ _ |
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* | a11 a12 | 1 0 | | X11 X12 | |
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* | | | = | | |
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* |_ a21 a22 | 0 1 _| |_ X21 X21 _| |
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* |
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* 2. In our implementation, pDst Matrix is used as identity matrix. |
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* |
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* 3. Begin with the first row. Let i = 1. |
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* |
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* 4. Check to see if the pivot for column i is the greatest of the column. |
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* The pivot is the element of the main diagonal that is on the current row. |
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* For instance, if working with row i, then the pivot element is aii. |
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* If the pivot is not the most significant of the columns, exchange that row with a row |
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* below it that does contain the most significant value in column i. If the most |
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* significant value of the column is zero, then an inverse to that matrix does not exist. |
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* The most significant value of the column is the absolute maximum. |
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* |
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* 5. Divide every element of row i by the pivot. |
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* |
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* 6. For every row below and row i, replace that row with the sum of that row and |
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* a multiple of row i so that each new element in column i below row i is zero. |
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* |
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* 7. Move to the next row and column and repeat steps 2 through 5 until you have zeros |
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* for every element below and above the main diagonal. |
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* |
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* 8. Now an identical matrix is formed to the left of the bar(input matrix, pSrc). |
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* Therefore, the matrix to the right of the bar is our solution(pDst matrix, pDst). |
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*----------------------------------------------------------------------------------------------------------------*/ |
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/* Working pointer for destination matrix */ |
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pOutT1 = pOut; |
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/* Loop over the number of rows */ |
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rowCnt = numRows; |
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/* Making the destination matrix as identity matrix */ |
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while(rowCnt > 0u) |
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{ |
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/* Writing all zeroes in lower triangle of the destination matrix */ |
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j = numRows - rowCnt; |
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while(j > 0u) |
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{ |
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*pOutT1++ = 0.0f; |
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j--; |
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} |
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/* Writing all ones in the diagonal of the destination matrix */ |
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*pOutT1++ = 1.0f; |
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/* Writing all zeroes in upper triangle of the destination matrix */ |
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j = rowCnt - 1u; |
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while(j > 0u) |
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{ |
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*pOutT1++ = 0.0f; |
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j--; |
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} |
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/* Decrement the loop counter */ |
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rowCnt--; |
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} |
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/* Loop over the number of columns of the input matrix. |
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All the elements in each column are processed by the row operations */ |
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loopCnt = numCols; |
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/* Index modifier to navigate through the columns */ |
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l = 0u; |
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while(loopCnt > 0u) |
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{ |
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/* Check if the pivot element is zero.. |
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* If it is zero then interchange the row with non zero row below. |
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* If there is no non zero element to replace in the rows below, |
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* then the matrix is Singular. */ |
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/* Working pointer for the input matrix that points |
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* to the pivot element of the particular row */ |
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pInT1 = pIn + (l * numCols); |
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/* Working pointer for the destination matrix that points |
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* to the pivot element of the particular row */ |
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pOutT1 = pOut + (l * numCols); |
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/* Temporary variable to hold the pivot value */ |
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in = *pInT1; |
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/* Grab the most significant value from column l */ |
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maxC = 0; |
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for (i = l; i < numRows; i++) |
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{ |
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maxC = *pInT1 > 0 ? (*pInT1 > maxC ? *pInT1 : maxC) : (-*pInT1 > maxC ? -*pInT1 : maxC); |
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pInT1 += numCols; |
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} |
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/* Update the status if the matrix is singular */ |
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if(maxC == 0.0f) |
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{ |
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return ARM_MATH_SINGULAR; |
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} |
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/* Restore pInT1 */ |
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pInT1 = pIn; |
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/* Destination pointer modifier */ |
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k = 1u; |
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/* Check if the pivot element is the most significant of the column */ |
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if( (in > 0.0f ? in : -in) != maxC) |
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{ |
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/* Loop over the number rows present below */ |
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i = numRows - (l + 1u); |
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while(i > 0u) |
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{ |
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/* Update the input and destination pointers */ |
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pInT2 = pInT1 + (numCols * l); |
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pOutT2 = pOutT1 + (numCols * k); |
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/* Look for the most significant element to |
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* replace in the rows below */ |
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if((*pInT2 > 0.0f ? *pInT2: -*pInT2) == maxC) |
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{ |
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/* Loop over number of columns |
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* to the right of the pilot element */ |
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j = numCols - l; |
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while(j > 0u) |
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{ |
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/* Exchange the row elements of the input matrix */ |
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Xchg = *pInT2; |
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*pInT2++ = *pInT1; |
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*pInT1++ = Xchg; |
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/* Decrement the loop counter */ |
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j--; |
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} |
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/* Loop over number of columns of the destination matrix */ |
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j = numCols; |
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while(j > 0u) |
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{ |
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/* Exchange the row elements of the destination matrix */ |
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Xchg = *pOutT2; |
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*pOutT2++ = *pOutT1; |
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*pOutT1++ = Xchg; |
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/* Decrement the loop counter */ |
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j--; |
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} |
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/* Flag to indicate whether exchange is done or not */ |
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flag = 1u; |
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/* Break after exchange is done */ |
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break; |
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} |
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/* Update the destination pointer modifier */ |
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k++; |
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/* Decrement the loop counter */ |
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i--; |
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} |
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} |
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/* Update the status if the matrix is singular */ |
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if((flag != 1u) && (in == 0.0f)) |
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{ |
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return ARM_MATH_SINGULAR; |
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} |
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/* Points to the pivot row of input and destination matrices */ |
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pPivotRowIn = pIn + (l * numCols); |
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pPivotRowDst = pOut + (l * numCols); |
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/* Temporary pointers to the pivot row pointers */ |
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pInT1 = pPivotRowIn; |
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pInT2 = pPivotRowDst; |
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/* Pivot element of the row */ |
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in = *pPivotRowIn; |
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/* Loop over number of columns |
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* to the right of the pilot element */ |
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j = (numCols - l); |
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while(j > 0u) |
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{ |
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/* Divide each element of the row of the input matrix |
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* by the pivot element */ |
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in1 = *pInT1; |
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*pInT1++ = in1 / in; |
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/* Decrement the loop counter */ |
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j--; |
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} |
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/* Loop over number of columns of the destination matrix */ |
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j = numCols; |
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while(j > 0u) |
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{ |
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/* Divide each element of the row of the destination matrix |
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* by the pivot element */ |
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in1 = *pInT2; |
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*pInT2++ = in1 / in; |
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/* Decrement the loop counter */ |
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j--; |
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} |
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/* Replace the rows with the sum of that row and a multiple of row i |
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* so that each new element in column i above row i is zero.*/ |
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/* Temporary pointers for input and destination matrices */ |
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pInT1 = pIn; |
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pInT2 = pOut; |
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/* index used to check for pivot element */ |
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i = 0u; |
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/* Loop over number of rows */ |
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/* to be replaced by the sum of that row and a multiple of row i */ |
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k = numRows; |
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while(k > 0u) |
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{ |
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/* Check for the pivot element */ |
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if(i == l) |
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{ |
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/* If the processing element is the pivot element, |
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only the columns to the right are to be processed */ |
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pInT1 += numCols - l; |
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pInT2 += numCols; |
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} |
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else |
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{ |
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/* Element of the reference row */ |
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in = *pInT1; |
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/* Working pointers for input and destination pivot rows */ |
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pPRT_in = pPivotRowIn; |
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pPRT_pDst = pPivotRowDst; |
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/* Loop over the number of columns to the right of the pivot element, |
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to replace the elements in the input matrix */ |
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j = (numCols - l); |
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while(j > 0u) |
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{ |
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/* Replace the element by the sum of that row |
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and a multiple of the reference row */ |
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in1 = *pInT1; |
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*pInT1++ = in1 - (in * *pPRT_in++); |
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/* Decrement the loop counter */ |
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j--; |
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} |
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/* Loop over the number of columns to |
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replace the elements in the destination matrix */ |
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j = numCols; |
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while(j > 0u) |
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{ |
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/* Replace the element by the sum of that row |
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and a multiple of the reference row */ |
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in1 = *pInT2; |
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*pInT2++ = in1 - (in * *pPRT_pDst++); |
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/* Decrement the loop counter */ |
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j--; |
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} |
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} |
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/* Increment the temporary input pointer */ |
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pInT1 = pInT1 + l; |
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/* Decrement the loop counter */ |
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k--; |
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/* Increment the pivot index */ |
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i++; |
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} |
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/* Increment the input pointer */ |
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pIn++; |
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/* Decrement the loop counter */ |
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loopCnt--; |
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/* Increment the index modifier */ |
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l++; |
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} |
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#else |
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/* Run the below code for Cortex-M0 */ |
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float64_t Xchg, in = 0.0f; /* Temporary input values */ |
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uint32_t i, rowCnt, flag = 0u, j, loopCnt, k, l; /* loop counters */ |
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arm_status status; /* status of matrix inverse */ |
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|
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#ifdef ARM_MATH_MATRIX_CHECK |
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|
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/* Check for matrix mismatch condition */ |
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if((pSrc->numRows != pSrc->numCols) || (pDst->numRows != pDst->numCols) |
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|| (pSrc->numRows != pDst->numRows)) |
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{ |
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/* Set status as ARM_MATH_SIZE_MISMATCH */ |
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status = ARM_MATH_SIZE_MISMATCH; |
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} |
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else |
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#endif /* #ifdef ARM_MATH_MATRIX_CHECK */ |
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{ |
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|
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/*-------------------------------------------------------------------------------------------------------------- |
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* Matrix Inverse can be solved using elementary row operations. |
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450 |
* |
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451 |
* Gauss-Jordan Method: |
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452 |
* |
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453 |
* 1. First combine the identity matrix and the input matrix separated by a bar to form an |
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* augmented matrix as follows: |
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* _ _ _ _ _ _ _ _ |
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* | | a11 a12 | | | 1 0 | | | X11 X12 | |
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* | | | | | | | = | | |
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* |_ |_ a21 a22 _| | |_0 1 _| _| |_ X21 X21 _| |
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* |
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* 2. In our implementation, pDst Matrix is used as identity matrix. |
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461 |
* |
|
462 |
* 3. Begin with the first row. Let i = 1. |
|
463 |
* |
|
464 |
* 4. Check to see if the pivot for row i is zero. |
|
465 |
* The pivot is the element of the main diagonal that is on the current row. |
|
466 |
* For instance, if working with row i, then the pivot element is aii. |
|
467 |
* If the pivot is zero, exchange that row with a row below it that does not |
|
468 |
* contain a zero in column i. If this is not possible, then an inverse |
|
469 |
* to that matrix does not exist. |
|
470 |
* |
|
471 |
* 5. Divide every element of row i by the pivot. |
|
472 |
* |
|
473 |
* 6. For every row below and row i, replace that row with the sum of that row and |
|
474 |
* a multiple of row i so that each new element in column i below row i is zero. |
|
475 |
* |
|
476 |
* 7. Move to the next row and column and repeat steps 2 through 5 until you have zeros |
|
477 |
* for every element below and above the main diagonal. |
|
478 |
* |
|
479 |
* 8. Now an identical matrix is formed to the left of the bar(input matrix, src). |
|
480 |
* Therefore, the matrix to the right of the bar is our solution(dst matrix, dst). |
|
481 |
*----------------------------------------------------------------------------------------------------------------*/ |
|
482 |
|
|
483 |
/* Working pointer for destination matrix */ |
|
484 |
pOutT1 = pOut; |
|
485 |
|
|
486 |
/* Loop over the number of rows */ |
|
487 |
rowCnt = numRows; |
|
488 |
|
|
489 |
/* Making the destination matrix as identity matrix */ |
|
490 |
while(rowCnt > 0u) |
|
491 |
{ |
|
492 |
/* Writing all zeroes in lower triangle of the destination matrix */ |
|
493 |
j = numRows - rowCnt; |
|
494 |
while(j > 0u) |
|
495 |
{ |
|
496 |
*pOutT1++ = 0.0f; |
|
497 |
j--; |
|
498 |
} |
|
499 |
|
|
500 |
/* Writing all ones in the diagonal of the destination matrix */ |
|
501 |
*pOutT1++ = 1.0f; |
|
502 |
|
|
503 |
/* Writing all zeroes in upper triangle of the destination matrix */ |
|
504 |
j = rowCnt - 1u; |
|
505 |
while(j > 0u) |
|
506 |
{ |
|
507 |
*pOutT1++ = 0.0f; |
|
508 |
j--; |
|
509 |
} |
|
510 |
|
|
511 |
/* Decrement the loop counter */ |
|
512 |
rowCnt--; |
|
513 |
} |
|
514 |
|
|
515 |
/* Loop over the number of columns of the input matrix. |
|
516 |
All the elements in each column are processed by the row operations */ |
|
517 |
loopCnt = numCols; |
|
518 |
|
|
519 |
/* Index modifier to navigate through the columns */ |
|
520 |
l = 0u; |
|
521 |
//for(loopCnt = 0u; loopCnt < numCols; loopCnt++) |
|
522 |
while(loopCnt > 0u) |
|
523 |
{ |
|
524 |
/* Check if the pivot element is zero.. |
|
525 |
* If it is zero then interchange the row with non zero row below. |
|
526 |
* If there is no non zero element to replace in the rows below, |
|
527 |
* then the matrix is Singular. */ |
|
528 |
|
|
529 |
/* Working pointer for the input matrix that points |
|
530 |
* to the pivot element of the particular row */ |
|
531 |
pInT1 = pIn + (l * numCols); |
|
532 |
|
|
533 |
/* Working pointer for the destination matrix that points |
|
534 |
* to the pivot element of the particular row */ |
|
535 |
pOutT1 = pOut + (l * numCols); |
|
536 |
|
|
537 |
/* Temporary variable to hold the pivot value */ |
|
538 |
in = *pInT1; |
|
539 |
|
|
540 |
/* Destination pointer modifier */ |
|
541 |
k = 1u; |
|
542 |
|
|
543 |
/* Check if the pivot element is zero */ |
|
544 |
if(*pInT1 == 0.0f) |
|
545 |
{ |
|
546 |
/* Loop over the number rows present below */ |
|
547 |
for (i = (l + 1u); i < numRows; i++) |
|
548 |
{ |
|
549 |
/* Update the input and destination pointers */ |
|
550 |
pInT2 = pInT1 + (numCols * l); |
|
551 |
pOutT2 = pOutT1 + (numCols * k); |
|
552 |
|
|
553 |
/* Check if there is a non zero pivot element to |
|
554 |
* replace in the rows below */ |
|
555 |
if(*pInT2 != 0.0f) |
|
556 |
{ |
|
557 |
/* Loop over number of columns |
|
558 |
* to the right of the pilot element */ |
|
559 |
for (j = 0u; j < (numCols - l); j++) |
|
560 |
{ |
|
561 |
/* Exchange the row elements of the input matrix */ |
|
562 |
Xchg = *pInT2; |
|
563 |
*pInT2++ = *pInT1; |
|
564 |
*pInT1++ = Xchg; |
|
565 |
} |
|
566 |
|
|
567 |
for (j = 0u; j < numCols; j++) |
|
568 |
{ |
|
569 |
Xchg = *pOutT2; |
|
570 |
*pOutT2++ = *pOutT1; |
|
571 |
*pOutT1++ = Xchg; |
|
572 |
} |
|
573 |
|
|
574 |
/* Flag to indicate whether exchange is done or not */ |
|
575 |
flag = 1u; |
|
576 |
|
|
577 |
/* Break after exchange is done */ |
|
578 |
break; |
|
579 |
} |
|
580 |
|
|
581 |
/* Update the destination pointer modifier */ |
|
582 |
k++; |
|
583 |
} |
|
584 |
} |
|
585 |
|
|
586 |
/* Update the status if the matrix is singular */ |
|
587 |
if((flag != 1u) && (in == 0.0f)) |
|
588 |
{ |
|
589 |
return ARM_MATH_SINGULAR; |
|
590 |
} |
|
591 |
|
|
592 |
/* Points to the pivot row of input and destination matrices */ |
|
593 |
pPivotRowIn = pIn + (l * numCols); |
|
594 |
pPivotRowDst = pOut + (l * numCols); |
|
595 |
|
|
596 |
/* Temporary pointers to the pivot row pointers */ |
|
597 |
pInT1 = pPivotRowIn; |
|
598 |
pOutT1 = pPivotRowDst; |
|
599 |
|
|
600 |
/* Pivot element of the row */ |
|
601 |
in = *(pIn + (l * numCols)); |
|
602 |
|
|
603 |
/* Loop over number of columns |
|
604 |
* to the right of the pilot element */ |
|
605 |
for (j = 0u; j < (numCols - l); j++) |
|
606 |
{ |
|
607 |
/* Divide each element of the row of the input matrix |
|
608 |
* by the pivot element */ |
|
609 |
*pInT1 = *pInT1 / in; |
|
610 |
pInT1++; |
|
611 |
} |
|
612 |
for (j = 0u; j < numCols; j++) |
|
613 |
{ |
|
614 |
/* Divide each element of the row of the destination matrix |
|
615 |
* by the pivot element */ |
|
616 |
*pOutT1 = *pOutT1 / in; |
|
617 |
pOutT1++; |
|
618 |
} |
|
619 |
|
|
620 |
/* Replace the rows with the sum of that row and a multiple of row i |
|
621 |
* so that each new element in column i above row i is zero.*/ |
|
622 |
|
|
623 |
/* Temporary pointers for input and destination matrices */ |
|
624 |
pInT1 = pIn; |
|
625 |
pOutT1 = pOut; |
|
626 |
|
|
627 |
for (i = 0u; i < numRows; i++) |
|
628 |
{ |
|
629 |
/* Check for the pivot element */ |
|
630 |
if(i == l) |
|
631 |
{ |
|
632 |
/* If the processing element is the pivot element, |
|
633 |
only the columns to the right are to be processed */ |
|
634 |
pInT1 += numCols - l; |
|
635 |
pOutT1 += numCols; |
|
636 |
} |
|
637 |
else |
|
638 |
{ |
|
639 |
/* Element of the reference row */ |
|
640 |
in = *pInT1; |
|
641 |
|
|
642 |
/* Working pointers for input and destination pivot rows */ |
|
643 |
pPRT_in = pPivotRowIn; |
|
644 |
pPRT_pDst = pPivotRowDst; |
|
645 |
|
|
646 |
/* Loop over the number of columns to the right of the pivot element, |
|
647 |
to replace the elements in the input matrix */ |
|
648 |
for (j = 0u; j < (numCols - l); j++) |
|
649 |
{ |
|
650 |
/* Replace the element by the sum of that row |
|
651 |
and a multiple of the reference row */ |
|
652 |
*pInT1 = *pInT1 - (in * *pPRT_in++); |
|
653 |
pInT1++; |
|
654 |
} |
|
655 |
/* Loop over the number of columns to |
|
656 |
replace the elements in the destination matrix */ |
|
657 |
for (j = 0u; j < numCols; j++) |
|
658 |
{ |
|
659 |
/* Replace the element by the sum of that row |
|
660 |
and a multiple of the reference row */ |
|
661 |
*pOutT1 = *pOutT1 - (in * *pPRT_pDst++); |
|
662 |
pOutT1++; |
|
663 |
} |
|
664 |
|
|
665 |
} |
|
666 |
/* Increment the temporary input pointer */ |
|
667 |
pInT1 = pInT1 + l; |
|
668 |
} |
|
669 |
/* Increment the input pointer */ |
|
670 |
pIn++; |
|
671 |
|
|
672 |
/* Decrement the loop counter */ |
|
673 |
loopCnt--; |
|
674 |
/* Increment the index modifier */ |
|
675 |
l++; |
|
676 |
} |
|
677 |
|
|
678 |
|
|
679 |
#endif /* #ifndef ARM_MATH_CM0_FAMILY */ |
|
680 |
|
|
681 |
/* Set status as ARM_MATH_SUCCESS */ |
|
682 |
status = ARM_MATH_SUCCESS; |
|
683 |
|
|
684 |
if((flag != 1u) && (in == 0.0f)) |
|
685 |
{ |
|
686 |
pIn = pSrc->pData; |
|
687 |
for (i = 0; i < numRows * numCols; i++) |
|
688 |
{ |
|
689 |
if (pIn[i] != 0.0f) |
|
690 |
break; |
|
691 |
} |
|
692 |
|
|
693 |
if (i == numRows * numCols) |
|
694 |
status = ARM_MATH_SINGULAR; |
|
695 |
} |
|
696 |
} |
|
697 |
/* Return to application */ |
|
698 |
return (status); |
|
699 |
} |
|
700 |
|
|
701 |
/** |
|
702 |
* @} end of MatrixInv group |
|
703 |
*/ |