692 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			692 lines
		
	
	
		
			22 KiB
		
	
	
	
		
			C
		
	
	
	
| /* ----------------------------------------------------------------------
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|  * Project:      CMSIS DSP Library
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|  * Title:        arm_mat_inverse_f32.c
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|  * Description:  Floating-point matrix inverse
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|  *
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|  * $Date:        27. January 2017
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|  * $Revision:    V.1.5.1
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|  *
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|  * Target Processor: Cortex-M cores
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|  * -------------------------------------------------------------------- */
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| /*
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|  * Copyright (C) 2010-2017 ARM Limited or its affiliates. All rights reserved.
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|  *
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|  * SPDX-License-Identifier: Apache-2.0
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|  *
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|  * Licensed under the Apache License, Version 2.0 (the License); you may
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|  * not use this file except in compliance with the License.
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|  * You may obtain a copy of the License at
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|  *
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|  * www.apache.org/licenses/LICENSE-2.0
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|  *
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|  * Unless required by applicable law or agreed to in writing, software
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|  * distributed under the License is distributed on an AS IS BASIS, WITHOUT
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|  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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|  * See the License for the specific language governing permissions and
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|  * limitations under the License.
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|  */
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| 
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| #include "arm_math.h"
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| 
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| /**
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|  * @ingroup groupMatrix
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|  */
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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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| /**
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|  * @addtogroup MatrixInv
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|  * @{
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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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| 
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| arm_status arm_mat_inverse_f32(
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|   const arm_matrix_instance_f32 * pSrc,
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|   arm_matrix_instance_f32 * pDst)
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| {
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|   float32_t *pIn = pSrc->pData;                  /* input data matrix pointer */
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|   float32_t *pOut = pDst->pData;                 /* output data matrix pointer */
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|   float32_t *pInT1, *pInT2;                      /* Temporary input data matrix pointer */
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|   float32_t *pOutT1, *pOutT2;                    /* Temporary output data matrix pointer */
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|   float32_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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| 
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| #if defined (ARM_MATH_DSP)
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|   float32_t maxC;                                /* maximum value in the column */
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| 
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|   /* Run the below code for Cortex-M4 and Cortex-M3 */
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| 
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|   float32_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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| 
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| #ifdef ARM_MATH_MATRIX_CHECK
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| 
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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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|     /*--------------------------------------------------------------------------------------------------------------
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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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| 
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|     /* Working pointer for destination matrix */
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|     pOutT1 = pOut;
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| 
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|     /* Loop over the number of rows */
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|     rowCnt = numRows;
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| 
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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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| 
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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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| 
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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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| 
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|       /* Decrement the loop counter */
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|       rowCnt--;
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|     }
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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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| 
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|     /* Index modifier to navigate through the columns */
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|     l = 0U;
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| 
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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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| 
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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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| 
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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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| 
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|       /* Temporary variable to hold the pivot value */
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|       in = *pInT1;
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| 
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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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| 
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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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| 
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|       /* Restore pInT1  */
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|       pInT1 = pIn;
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| 
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|       /* Destination pointer modifier */
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|       k = 1U;
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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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|             /* Loop over number of columns of the destination matrix */
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|             j = numCols;
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| 
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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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| 
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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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|             /* Flag to indicate whether exchange is done or not */
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|             flag = 1U;
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| 
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|             /* Break after exchange is done */
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|             break;
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|           }
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| 
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|           /* Update the destination pointer modifier */
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|           k++;
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| 
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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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| 
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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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| 
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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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| 
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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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| 
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|       /* Pivot element of the row */
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|       in = *pPivotRowIn;
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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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| 
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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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| 
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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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|       /* Loop over number of columns of the destination matrix */
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|       j = numCols;
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| 
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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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| 
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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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|       /* 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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| 
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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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| 
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|       /* index used to check for pivot element */
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|       i = 0U;
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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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| 
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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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|           /* 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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| 
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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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| 
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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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|         }
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| 
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|         /* Increment the temporary input pointer */
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|         pInT1 = pInT1 + l;
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| 
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|         /* Decrement the loop counter */
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|         k--;
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| 
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|         /* Increment the pivot index */
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|         i++;
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|       }
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| 
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|       /* Increment the input pointer */
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|       pIn++;
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| 
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|       /* Decrement the loop counter */
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|       loopCnt--;
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| 
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|       /* Increment the index modifier */
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|       l++;
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|     }
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| 
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| 
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| #else
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| 
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|   /* Run the below code for Cortex-M0 */
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| 
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|   float32_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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| 	 * Matrix Inverse can be solved using elementary row operations.
 | |
| 	 *
 | |
| 	 *	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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| 	 *					   |  |  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 row i is zero.
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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.
 | |
| 	 *		   If the pivot is zero, exchange that row with a row below it that does not
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| 	 *		   contain a zero in column i. If this is not possible, then an inverse
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| 	 *		   to that matrix does not exist.
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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, src).
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| 	 *		   Therefore, the matrix to the right of the bar is our solution(dst matrix, dst).
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| 	 *----------------------------------------------------------------------------------------------------------------*/
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| 
 | |
|     /* Working pointer for destination matrix */
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|     pOutT1 = pOut;
 | |
| 
 | |
|     /* Loop over the number of rows */
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|     rowCnt = numRows;
 | |
| 
 | |
|     /* Making the destination matrix as identity matrix */
 | |
|     while (rowCnt > 0U)
 | |
|     {
 | |
|       /* Writing all zeroes in lower triangle of the destination matrix */
 | |
|       j = numRows - rowCnt;
 | |
|       while (j > 0U)
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|       {
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|         *pOutT1++ = 0.0f;
 | |
|         j--;
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|       }
 | |
| 
 | |
|       /* Writing all ones in the diagonal of the destination matrix */
 | |
|       *pOutT1++ = 1.0f;
 | |
| 
 | |
|       /* Writing all zeroes in upper triangle of the destination matrix */
 | |
|       j = rowCnt - 1U;
 | |
|       while (j > 0U)
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|       {
 | |
|         *pOutT1++ = 0.0f;
 | |
|         j--;
 | |
|       }
 | |
| 
 | |
|       /* Decrement the loop counter */
 | |
|       rowCnt--;
 | |
|     }
 | |
| 
 | |
|     /* Loop over the number of columns of the input matrix.
 | |
|        All the elements in each column are processed by the row operations */
 | |
|     loopCnt = numCols;
 | |
| 
 | |
|     /* Index modifier to navigate through the columns */
 | |
|     l = 0U;
 | |
|     //for(loopCnt = 0U; loopCnt < numCols; loopCnt++)
 | |
|     while (loopCnt > 0U)
 | |
|     {
 | |
|       /* Check if the pivot element is zero..
 | |
|        * If it is zero then interchange the row with non zero row below.
 | |
|        * If there is no non zero element to replace in the rows below,
 | |
|        * then the matrix is Singular. */
 | |
| 
 | |
|       /* Working pointer for the input matrix that points
 | |
|        * to the pivot element of the particular row  */
 | |
|       pInT1 = pIn + (l * numCols);
 | |
| 
 | |
|       /* Working pointer for the destination matrix that points
 | |
|        * to the pivot element of the particular row  */
 | |
|       pOutT1 = pOut + (l * numCols);
 | |
| 
 | |
|       /* Temporary variable to hold the pivot value */
 | |
|       in = *pInT1;
 | |
| 
 | |
|       /* Destination pointer modifier */
 | |
|       k = 1U;
 | |
| 
 | |
|       /* Check if the pivot element is zero */
 | |
|       if (*pInT1 == 0.0f)
 | |
|       {
 | |
|         /* Loop over the number rows present below */
 | |
|         for (i = (l + 1U); i < numRows; i++)
 | |
|         {
 | |
|           /* Update the input and destination pointers */
 | |
|           pInT2 = pInT1 + (numCols * l);
 | |
|           pOutT2 = pOutT1 + (numCols * k);
 | |
| 
 | |
|           /* Check if there is a non zero pivot element to
 | |
|            * replace in the rows below */
 | |
|           if (*pInT2 != 0.0f)
 | |
|           {
 | |
|             /* Loop over number of columns
 | |
|              * to the right of the pilot element */
 | |
|             for (j = 0U; j < (numCols - l); j++)
 | |
|             {
 | |
|               /* Exchange the row elements of the input matrix */
 | |
|               Xchg = *pInT2;
 | |
|               *pInT2++ = *pInT1;
 | |
|               *pInT1++ = Xchg;
 | |
|             }
 | |
| 
 | |
|             for (j = 0U; j < numCols; j++)
 | |
|             {
 | |
|               Xchg = *pOutT2;
 | |
|               *pOutT2++ = *pOutT1;
 | |
|               *pOutT1++ = Xchg;
 | |
|             }
 | |
| 
 | |
|             /* Flag to indicate whether exchange is done or not */
 | |
|             flag = 1U;
 | |
| 
 | |
|             /* Break after exchange is done */
 | |
|             break;
 | |
|           }
 | |
| 
 | |
|           /* Update the destination pointer modifier */
 | |
|           k++;
 | |
|         }
 | |
|       }
 | |
| 
 | |
|       /* Update the status if the matrix is singular */
 | |
|       if ((flag != 1U) && (in == 0.0f))
 | |
|       {
 | |
|         return ARM_MATH_SINGULAR;
 | |
|       }
 | |
| 
 | |
|       /* Points to the pivot row of input and destination matrices */
 | |
|       pPivotRowIn = pIn + (l * numCols);
 | |
|       pPivotRowDst = pOut + (l * numCols);
 | |
| 
 | |
|       /* Temporary pointers to the pivot row pointers */
 | |
|       pInT1 = pPivotRowIn;
 | |
|       pOutT1 = pPivotRowDst;
 | |
| 
 | |
|       /* Pivot element of the row */
 | |
|       in = *(pIn + (l * numCols));
 | |
| 
 | |
|       /* Loop over number of columns
 | |
|        * to the right of the pilot element */
 | |
|       for (j = 0U; j < (numCols - l); j++)
 | |
|       {
 | |
|         /* Divide each element of the row of the input matrix
 | |
|          * by the pivot element */
 | |
|         *pInT1 = *pInT1 / in;
 | |
|         pInT1++;
 | |
|       }
 | |
|       for (j = 0U; j < numCols; j++)
 | |
|       {
 | |
|         /* Divide each element of the row of the destination matrix
 | |
|          * by the pivot element */
 | |
|         *pOutT1 = *pOutT1 / in;
 | |
|         pOutT1++;
 | |
|       }
 | |
| 
 | |
|       /* Replace the rows with the sum of that row and a multiple of row i
 | |
|        * so that each new element in column i above row i is zero.*/
 | |
| 
 | |
|       /* Temporary pointers for input and destination matrices */
 | |
|       pInT1 = pIn;
 | |
|       pOutT1 = pOut;
 | |
| 
 | |
|       for (i = 0U; i < numRows; i++)
 | |
|       {
 | |
|         /* Check for the pivot element */
 | |
|         if (i == l)
 | |
|         {
 | |
|           /* If the processing element is the pivot element,
 | |
|              only the columns to the right are to be processed */
 | |
|           pInT1 += numCols - l;
 | |
|           pOutT1 += numCols;
 | |
|         }
 | |
|         else
 | |
|         {
 | |
|           /* Element of the reference row */
 | |
|           in = *pInT1;
 | |
| 
 | |
|           /* Working pointers for input and destination pivot rows */
 | |
|           pPRT_in = pPivotRowIn;
 | |
|           pPRT_pDst = pPivotRowDst;
 | |
| 
 | |
|           /* Loop over the number of columns to the right of the pivot element,
 | |
|              to replace the elements in the input matrix */
 | |
|           for (j = 0U; j < (numCols - l); j++)
 | |
|           {
 | |
|             /* Replace the element by the sum of that row
 | |
|                and a multiple of the reference row  */
 | |
|             *pInT1 = *pInT1 - (in * *pPRT_in++);
 | |
|             pInT1++;
 | |
|           }
 | |
|           /* Loop over the number of columns to
 | |
|              replace the elements in the destination matrix */
 | |
|           for (j = 0U; j < numCols; j++)
 | |
|           {
 | |
|             /* Replace the element by the sum of that row
 | |
|                and a multiple of the reference row  */
 | |
|             *pOutT1 = *pOutT1 - (in * *pPRT_pDst++);
 | |
|             pOutT1++;
 | |
|           }
 | |
| 
 | |
|         }
 | |
|         /* Increment the temporary input pointer */
 | |
|         pInT1 = pInT1 + l;
 | |
|       }
 | |
|       /* Increment the input pointer */
 | |
|       pIn++;
 | |
| 
 | |
|       /* Decrement the loop counter */
 | |
|       loopCnt--;
 | |
|       /* Increment the index modifier */
 | |
|       l++;
 | |
|     }
 | |
| 
 | |
| 
 | |
| #endif /* #if defined (ARM_MATH_DSP) */
 | |
| 
 | |
|     /* Set status as ARM_MATH_SUCCESS */
 | |
|     status = ARM_MATH_SUCCESS;
 | |
| 
 | |
|     if ((flag != 1U) && (in == 0.0f))
 | |
|     {
 | |
|       pIn = pSrc->pData;
 | |
|       for (i = 0; i < numRows * numCols; i++)
 | |
|       {
 | |
|         if (pIn[i] != 0.0f)
 | |
|             break;
 | |
|       }
 | |
| 
 | |
|       if (i == numRows * numCols)
 | |
|         status = ARM_MATH_SINGULAR;
 | |
|     }
 | |
|   }
 | |
|   /* Return to application */
 | |
|   return (status);
 | |
| }
 | |
| 
 | |
| /**
 | |
|  * @} end of MatrixInv group
 | |
|  */
 |