Laxmi Kant Tiwari
CMSIS DSP Lib
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mbed official
cmsis_dsp/MatrixFunctions/arm_mat_inverse_f32.c@3:7a284390b0ce, 2013-11-08 (annotated)
- Committer:
- mbed_official
- Date:
- Fri Nov 08 13:45:10 2013 +0000
- Revision:
- 3:7a284390b0ce
- Parent:
- 2:da51fb522205
Synchronized with git revision e69956aba2f68a2a26ac26b051f8d349deaa1ce8
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| emilmont | 1:fdd22bb7aa52 | 1 | /* ---------------------------------------------------------------------- |
| mbed_official | 3:7a284390b0ce | 2 | * Copyright (C) 2010-2013 ARM Limited. All rights reserved. |
| emilmont | 1:fdd22bb7aa52 | 3 | * |
| mbed_official | 3:7a284390b0ce | 4 | * $Date: 1. March 2013 |
| mbed_official | 3:7a284390b0ce | 5 | * $Revision: V1.4.1 |
| emilmont | 1:fdd22bb7aa52 | 6 | * |
| emilmont | 2:da51fb522205 | 7 | * Project: CMSIS DSP Library |
| emilmont | 2:da51fb522205 | 8 | * Title: arm_mat_inverse_f32.c |
| emilmont | 1:fdd22bb7aa52 | 9 | * |
| emilmont | 2:da51fb522205 | 10 | * Description: Floating-point matrix inverse. |
| emilmont | 1:fdd22bb7aa52 | 11 | * |
| emilmont | 1:fdd22bb7aa52 | 12 | * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0 |
| emilmont | 1:fdd22bb7aa52 | 13 | * |
| mbed_official | 3:7a284390b0ce | 14 | * Redistribution and use in source and binary forms, with or without |
| mbed_official | 3:7a284390b0ce | 15 | * modification, are permitted provided that the following conditions |
| mbed_official | 3:7a284390b0ce | 16 | * are met: |
| mbed_official | 3:7a284390b0ce | 17 | * - Redistributions of source code must retain the above copyright |
| mbed_official | 3:7a284390b0ce | 18 | * notice, this list of conditions and the following disclaimer. |
| mbed_official | 3:7a284390b0ce | 19 | * - Redistributions in binary form must reproduce the above copyright |
| mbed_official | 3:7a284390b0ce | 20 | * notice, this list of conditions and the following disclaimer in |
| mbed_official | 3:7a284390b0ce | 21 | * the documentation and/or other materials provided with the |
| mbed_official | 3:7a284390b0ce | 22 | * distribution. |
| mbed_official | 3:7a284390b0ce | 23 | * - Neither the name of ARM LIMITED nor the names of its contributors |
| mbed_official | 3:7a284390b0ce | 24 | * may be used to endorse or promote products derived from this |
| mbed_official | 3:7a284390b0ce | 25 | * software without specific prior written permission. |
| mbed_official | 3:7a284390b0ce | 26 | * |
| mbed_official | 3:7a284390b0ce | 27 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
| mbed_official | 3:7a284390b0ce | 28 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
| mbed_official | 3:7a284390b0ce | 29 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS |
| mbed_official | 3:7a284390b0ce | 30 | * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE |
| mbed_official | 3:7a284390b0ce | 31 | * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, |
| mbed_official | 3:7a284390b0ce | 32 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, |
| mbed_official | 3:7a284390b0ce | 33 | * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; |
| mbed_official | 3:7a284390b0ce | 34 | * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER |
| mbed_official | 3:7a284390b0ce | 35 | * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT |
| mbed_official | 3:7a284390b0ce | 36 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN |
| mbed_official | 3:7a284390b0ce | 37 | * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| mbed_official | 3:7a284390b0ce | 38 | * POSSIBILITY OF SUCH DAMAGE. |
| emilmont | 1:fdd22bb7aa52 | 39 | * -------------------------------------------------------------------- */ |
| emilmont | 1:fdd22bb7aa52 | 40 | |
| emilmont | 1:fdd22bb7aa52 | 41 | #include "arm_math.h" |
| emilmont | 1:fdd22bb7aa52 | 42 | |
| emilmont | 1:fdd22bb7aa52 | 43 | /** |
| emilmont | 1:fdd22bb7aa52 | 44 | * @ingroup groupMatrix |
| emilmont | 1:fdd22bb7aa52 | 45 | */ |
| emilmont | 1:fdd22bb7aa52 | 46 | |
| emilmont | 1:fdd22bb7aa52 | 47 | /** |
| emilmont | 1:fdd22bb7aa52 | 48 | * @defgroup MatrixInv Matrix Inverse |
| emilmont | 1:fdd22bb7aa52 | 49 | * |
| emilmont | 1:fdd22bb7aa52 | 50 | * Computes the inverse of a matrix. |
| emilmont | 1:fdd22bb7aa52 | 51 | * |
| emilmont | 1:fdd22bb7aa52 | 52 | * The inverse is defined only if the input matrix is square and non-singular (the determinant |
| emilmont | 1:fdd22bb7aa52 | 53 | * is non-zero). The function checks that the input and output matrices are square and of the |
| emilmont | 1:fdd22bb7aa52 | 54 | * same size. |
| emilmont | 1:fdd22bb7aa52 | 55 | * |
| emilmont | 1:fdd22bb7aa52 | 56 | * Matrix inversion is numerically sensitive and the CMSIS DSP library only supports matrix |
| emilmont | 1:fdd22bb7aa52 | 57 | * inversion of floating-point matrices. |
| emilmont | 1:fdd22bb7aa52 | 58 | * |
| emilmont | 1:fdd22bb7aa52 | 59 | * \par Algorithm |
| emilmont | 1:fdd22bb7aa52 | 60 | * The Gauss-Jordan method is used to find the inverse. |
| emilmont | 1:fdd22bb7aa52 | 61 | * The algorithm performs a sequence of elementary row-operations till it |
| emilmont | 1:fdd22bb7aa52 | 62 | * reduces the input matrix to an identity matrix. Applying the same sequence |
| emilmont | 1:fdd22bb7aa52 | 63 | * of elementary row-operations to an identity matrix yields the inverse matrix. |
| emilmont | 1:fdd22bb7aa52 | 64 | * If the input matrix is singular, then the algorithm terminates and returns error status |
| emilmont | 1:fdd22bb7aa52 | 65 | * <code>ARM_MATH_SINGULAR</code>. |
| emilmont | 1:fdd22bb7aa52 | 66 | * \image html MatrixInverse.gif "Matrix Inverse of a 3 x 3 matrix using Gauss-Jordan Method" |
| emilmont | 1:fdd22bb7aa52 | 67 | */ |
| emilmont | 1:fdd22bb7aa52 | 68 | |
| emilmont | 1:fdd22bb7aa52 | 69 | /** |
| emilmont | 1:fdd22bb7aa52 | 70 | * @addtogroup MatrixInv |
| emilmont | 1:fdd22bb7aa52 | 71 | * @{ |
| emilmont | 1:fdd22bb7aa52 | 72 | */ |
| emilmont | 1:fdd22bb7aa52 | 73 | |
| emilmont | 1:fdd22bb7aa52 | 74 | /** |
| emilmont | 1:fdd22bb7aa52 | 75 | * @brief Floating-point matrix inverse. |
| emilmont | 1:fdd22bb7aa52 | 76 | * @param[in] *pSrc points to input matrix structure |
| emilmont | 1:fdd22bb7aa52 | 77 | * @param[out] *pDst points to output matrix structure |
| emilmont | 2:da51fb522205 | 78 | * @return The function returns |
| emilmont | 1:fdd22bb7aa52 | 79 | * <code>ARM_MATH_SIZE_MISMATCH</code> if the input matrix is not square or if the size |
| emilmont | 1:fdd22bb7aa52 | 80 | * of the output matrix does not match the size of the input matrix. |
| emilmont | 1:fdd22bb7aa52 | 81 | * If the input matrix is found to be singular (non-invertible), then the function returns |
| emilmont | 1:fdd22bb7aa52 | 82 | * <code>ARM_MATH_SINGULAR</code>. Otherwise, the function returns <code>ARM_MATH_SUCCESS</code>. |
| emilmont | 1:fdd22bb7aa52 | 83 | */ |
| emilmont | 1:fdd22bb7aa52 | 84 | |
| emilmont | 1:fdd22bb7aa52 | 85 | arm_status arm_mat_inverse_f32( |
| emilmont | 1:fdd22bb7aa52 | 86 | const arm_matrix_instance_f32 * pSrc, |
| emilmont | 1:fdd22bb7aa52 | 87 | arm_matrix_instance_f32 * pDst) |
| emilmont | 1:fdd22bb7aa52 | 88 | { |
| emilmont | 1:fdd22bb7aa52 | 89 | float32_t *pIn = pSrc->pData; /* input data matrix pointer */ |
| emilmont | 1:fdd22bb7aa52 | 90 | float32_t *pOut = pDst->pData; /* output data matrix pointer */ |
| emilmont | 1:fdd22bb7aa52 | 91 | float32_t *pInT1, *pInT2; /* Temporary input data matrix pointer */ |
| emilmont | 1:fdd22bb7aa52 | 92 | float32_t *pInT3, *pInT4; /* Temporary output data matrix pointer */ |
| emilmont | 1:fdd22bb7aa52 | 93 | float32_t *pPivotRowIn, *pPRT_in, *pPivotRowDst, *pPRT_pDst; /* Temporary input and output data matrix pointer */ |
| emilmont | 1:fdd22bb7aa52 | 94 | uint32_t numRows = pSrc->numRows; /* Number of rows in the matrix */ |
| emilmont | 1:fdd22bb7aa52 | 95 | uint32_t numCols = pSrc->numCols; /* Number of Cols in the matrix */ |
| emilmont | 1:fdd22bb7aa52 | 96 | |
| mbed_official | 3:7a284390b0ce | 97 | #ifndef ARM_MATH_CM0_FAMILY |
| mbed_official | 3:7a284390b0ce | 98 | float32_t maxC; /* maximum value in the column */ |
| emilmont | 1:fdd22bb7aa52 | 99 | |
| emilmont | 1:fdd22bb7aa52 | 100 | /* Run the below code for Cortex-M4 and Cortex-M3 */ |
| emilmont | 1:fdd22bb7aa52 | 101 | |
| emilmont | 1:fdd22bb7aa52 | 102 | float32_t Xchg, in = 0.0f, in1; /* Temporary input values */ |
| emilmont | 1:fdd22bb7aa52 | 103 | uint32_t i, rowCnt, flag = 0u, j, loopCnt, k, l; /* loop counters */ |
| emilmont | 1:fdd22bb7aa52 | 104 | arm_status status; /* status of matrix inverse */ |
| emilmont | 1:fdd22bb7aa52 | 105 | |
| emilmont | 1:fdd22bb7aa52 | 106 | #ifdef ARM_MATH_MATRIX_CHECK |
| emilmont | 1:fdd22bb7aa52 | 107 | |
| emilmont | 1:fdd22bb7aa52 | 108 | |
| emilmont | 1:fdd22bb7aa52 | 109 | /* Check for matrix mismatch condition */ |
| emilmont | 1:fdd22bb7aa52 | 110 | if((pSrc->numRows != pSrc->numCols) || (pDst->numRows != pDst->numCols) |
| emilmont | 1:fdd22bb7aa52 | 111 | || (pSrc->numRows != pDst->numRows)) |
| emilmont | 1:fdd22bb7aa52 | 112 | { |
| emilmont | 1:fdd22bb7aa52 | 113 | /* Set status as ARM_MATH_SIZE_MISMATCH */ |
| emilmont | 1:fdd22bb7aa52 | 114 | status = ARM_MATH_SIZE_MISMATCH; |
| emilmont | 1:fdd22bb7aa52 | 115 | } |
| emilmont | 1:fdd22bb7aa52 | 116 | else |
| emilmont | 1:fdd22bb7aa52 | 117 | #endif /* #ifdef ARM_MATH_MATRIX_CHECK */ |
| emilmont | 1:fdd22bb7aa52 | 118 | |
| emilmont | 1:fdd22bb7aa52 | 119 | { |
| emilmont | 1:fdd22bb7aa52 | 120 | |
| emilmont | 1:fdd22bb7aa52 | 121 | /*-------------------------------------------------------------------------------------------------------------- |
| emilmont | 2:da51fb522205 | 122 | * Matrix Inverse can be solved using elementary row operations. |
| emilmont | 2:da51fb522205 | 123 | * |
| emilmont | 2:da51fb522205 | 124 | * Gauss-Jordan Method: |
| emilmont | 2:da51fb522205 | 125 | * |
| emilmont | 2:da51fb522205 | 126 | * 1. First combine the identity matrix and the input matrix separated by a bar to form an |
| emilmont | 2:da51fb522205 | 127 | * augmented matrix as follows: |
| emilmont | 2:da51fb522205 | 128 | * _ _ _ _ |
| emilmont | 2:da51fb522205 | 129 | * | a11 a12 | 1 0 | | X11 X12 | |
| emilmont | 2:da51fb522205 | 130 | * | | | = | | |
| emilmont | 2:da51fb522205 | 131 | * |_ a21 a22 | 0 1 _| |_ X21 X21 _| |
| emilmont | 2:da51fb522205 | 132 | * |
| emilmont | 2:da51fb522205 | 133 | * 2. In our implementation, pDst Matrix is used as identity matrix. |
| emilmont | 2:da51fb522205 | 134 | * |
| emilmont | 2:da51fb522205 | 135 | * 3. Begin with the first row. Let i = 1. |
| emilmont | 2:da51fb522205 | 136 | * |
| mbed_official | 3:7a284390b0ce | 137 | * 4. Check to see if the pivot for column i is the greatest of the column. |
| emilmont | 2:da51fb522205 | 138 | * The pivot is the element of the main diagonal that is on the current row. |
| emilmont | 2:da51fb522205 | 139 | * For instance, if working with row i, then the pivot element is aii. |
| mbed_official | 3:7a284390b0ce | 140 | * If the pivot is not the most significant of the coluimns, exchange that row with a row |
| mbed_official | 3:7a284390b0ce | 141 | * below it that does contain the most significant value in column i. If the most |
| mbed_official | 3:7a284390b0ce | 142 | * significant value of the column is zero, then an inverse to that matrix does not exist. |
| mbed_official | 3:7a284390b0ce | 143 | * The most significant value of the column is the absolut maximum. |
| emilmont | 2:da51fb522205 | 144 | * |
| emilmont | 2:da51fb522205 | 145 | * 5. Divide every element of row i by the pivot. |
| emilmont | 2:da51fb522205 | 146 | * |
| emilmont | 2:da51fb522205 | 147 | * 6. For every row below and row i, replace that row with the sum of that row and |
| emilmont | 2:da51fb522205 | 148 | * a multiple of row i so that each new element in column i below row i is zero. |
| emilmont | 2:da51fb522205 | 149 | * |
| emilmont | 2:da51fb522205 | 150 | * 7. Move to the next row and column and repeat steps 2 through 5 until you have zeros |
| emilmont | 2:da51fb522205 | 151 | * for every element below and above the main diagonal. |
| emilmont | 2:da51fb522205 | 152 | * |
| emilmont | 2:da51fb522205 | 153 | * 8. Now an identical matrix is formed to the left of the bar(input matrix, pSrc). |
| emilmont | 2:da51fb522205 | 154 | * Therefore, the matrix to the right of the bar is our solution(pDst matrix, pDst). |
| emilmont | 2:da51fb522205 | 155 | *----------------------------------------------------------------------------------------------------------------*/ |
| emilmont | 1:fdd22bb7aa52 | 156 | |
| emilmont | 1:fdd22bb7aa52 | 157 | /* Working pointer for destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 158 | pInT2 = pOut; |
| emilmont | 1:fdd22bb7aa52 | 159 | |
| emilmont | 1:fdd22bb7aa52 | 160 | /* Loop over the number of rows */ |
| emilmont | 1:fdd22bb7aa52 | 161 | rowCnt = numRows; |
| emilmont | 1:fdd22bb7aa52 | 162 | |
| emilmont | 1:fdd22bb7aa52 | 163 | /* Making the destination matrix as identity matrix */ |
| emilmont | 1:fdd22bb7aa52 | 164 | while(rowCnt > 0u) |
| emilmont | 1:fdd22bb7aa52 | 165 | { |
| emilmont | 1:fdd22bb7aa52 | 166 | /* Writing all zeroes in lower triangle of the destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 167 | j = numRows - rowCnt; |
| emilmont | 1:fdd22bb7aa52 | 168 | while(j > 0u) |
| emilmont | 1:fdd22bb7aa52 | 169 | { |
| emilmont | 1:fdd22bb7aa52 | 170 | *pInT2++ = 0.0f; |
| emilmont | 1:fdd22bb7aa52 | 171 | j--; |
| emilmont | 1:fdd22bb7aa52 | 172 | } |
| emilmont | 1:fdd22bb7aa52 | 173 | |
| emilmont | 1:fdd22bb7aa52 | 174 | /* Writing all ones in the diagonal of the destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 175 | *pInT2++ = 1.0f; |
| emilmont | 1:fdd22bb7aa52 | 176 | |
| emilmont | 1:fdd22bb7aa52 | 177 | /* Writing all zeroes in upper triangle of the destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 178 | j = rowCnt - 1u; |
| emilmont | 1:fdd22bb7aa52 | 179 | while(j > 0u) |
| emilmont | 1:fdd22bb7aa52 | 180 | { |
| emilmont | 1:fdd22bb7aa52 | 181 | *pInT2++ = 0.0f; |
| emilmont | 1:fdd22bb7aa52 | 182 | j--; |
| emilmont | 1:fdd22bb7aa52 | 183 | } |
| emilmont | 1:fdd22bb7aa52 | 184 | |
| emilmont | 1:fdd22bb7aa52 | 185 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 186 | rowCnt--; |
| emilmont | 1:fdd22bb7aa52 | 187 | } |
| emilmont | 1:fdd22bb7aa52 | 188 | |
| emilmont | 1:fdd22bb7aa52 | 189 | /* Loop over the number of columns of the input matrix. |
| emilmont | 1:fdd22bb7aa52 | 190 | All the elements in each column are processed by the row operations */ |
| emilmont | 1:fdd22bb7aa52 | 191 | loopCnt = numCols; |
| emilmont | 1:fdd22bb7aa52 | 192 | |
| emilmont | 1:fdd22bb7aa52 | 193 | /* Index modifier to navigate through the columns */ |
| emilmont | 1:fdd22bb7aa52 | 194 | l = 0u; |
| emilmont | 1:fdd22bb7aa52 | 195 | |
| emilmont | 1:fdd22bb7aa52 | 196 | while(loopCnt > 0u) |
| emilmont | 1:fdd22bb7aa52 | 197 | { |
| emilmont | 1:fdd22bb7aa52 | 198 | /* Check if the pivot element is zero.. |
| emilmont | 1:fdd22bb7aa52 | 199 | * If it is zero then interchange the row with non zero row below. |
| emilmont | 1:fdd22bb7aa52 | 200 | * If there is no non zero element to replace in the rows below, |
| emilmont | 1:fdd22bb7aa52 | 201 | * then the matrix is Singular. */ |
| emilmont | 1:fdd22bb7aa52 | 202 | |
| emilmont | 1:fdd22bb7aa52 | 203 | /* Working pointer for the input matrix that points |
| emilmont | 1:fdd22bb7aa52 | 204 | * to the pivot element of the particular row */ |
| emilmont | 1:fdd22bb7aa52 | 205 | pInT1 = pIn + (l * numCols); |
| emilmont | 1:fdd22bb7aa52 | 206 | |
| emilmont | 1:fdd22bb7aa52 | 207 | /* Working pointer for the destination matrix that points |
| emilmont | 1:fdd22bb7aa52 | 208 | * to the pivot element of the particular row */ |
| emilmont | 1:fdd22bb7aa52 | 209 | pInT3 = pOut + (l * numCols); |
| emilmont | 1:fdd22bb7aa52 | 210 | |
| emilmont | 1:fdd22bb7aa52 | 211 | /* Temporary variable to hold the pivot value */ |
| emilmont | 1:fdd22bb7aa52 | 212 | in = *pInT1; |
| emilmont | 1:fdd22bb7aa52 | 213 | |
| emilmont | 1:fdd22bb7aa52 | 214 | /* Destination pointer modifier */ |
| emilmont | 1:fdd22bb7aa52 | 215 | k = 1u; |
| emilmont | 1:fdd22bb7aa52 | 216 | |
| mbed_official | 3:7a284390b0ce | 217 | /* Grab the most significant value from column l */ |
| mbed_official | 3:7a284390b0ce | 218 | maxC = 0; |
| mbed_official | 3:7a284390b0ce | 219 | for (i = 0; i < numRows; i++) |
| mbed_official | 3:7a284390b0ce | 220 | { |
| mbed_official | 3:7a284390b0ce | 221 | maxC = *pInT1 > 0 ? (*pInT1 > maxC ? *pInT1 : maxC) : (-*pInT1 > maxC ? -*pInT1 : maxC); |
| mbed_official | 3:7a284390b0ce | 222 | pInT1 += numCols; |
| mbed_official | 3:7a284390b0ce | 223 | } |
| mbed_official | 3:7a284390b0ce | 224 | |
| mbed_official | 3:7a284390b0ce | 225 | /* Update the status if the matrix is singular */ |
| mbed_official | 3:7a284390b0ce | 226 | if(maxC == 0.0f) |
| mbed_official | 3:7a284390b0ce | 227 | { |
| mbed_official | 3:7a284390b0ce | 228 | status = ARM_MATH_SINGULAR; |
| mbed_official | 3:7a284390b0ce | 229 | break; |
| mbed_official | 3:7a284390b0ce | 230 | } |
| mbed_official | 3:7a284390b0ce | 231 | |
| mbed_official | 3:7a284390b0ce | 232 | /* Restore pInT1 */ |
| mbed_official | 3:7a284390b0ce | 233 | pInT1 -= numRows * numCols; |
| mbed_official | 3:7a284390b0ce | 234 | |
| mbed_official | 3:7a284390b0ce | 235 | /* Check if the pivot element is the most significant of the column */ |
| mbed_official | 3:7a284390b0ce | 236 | if( (in > 0.0f ? in : -in) != maxC) |
| emilmont | 1:fdd22bb7aa52 | 237 | { |
| emilmont | 1:fdd22bb7aa52 | 238 | /* Loop over the number rows present below */ |
| emilmont | 1:fdd22bb7aa52 | 239 | i = numRows - (l + 1u); |
| emilmont | 1:fdd22bb7aa52 | 240 | |
| emilmont | 1:fdd22bb7aa52 | 241 | while(i > 0u) |
| emilmont | 1:fdd22bb7aa52 | 242 | { |
| emilmont | 1:fdd22bb7aa52 | 243 | /* Update the input and destination pointers */ |
| emilmont | 1:fdd22bb7aa52 | 244 | pInT2 = pInT1 + (numCols * l); |
| emilmont | 1:fdd22bb7aa52 | 245 | pInT4 = pInT3 + (numCols * k); |
| emilmont | 1:fdd22bb7aa52 | 246 | |
| mbed_official | 3:7a284390b0ce | 247 | /* Look for the most significant element to |
| emilmont | 1:fdd22bb7aa52 | 248 | * replace in the rows below */ |
| mbed_official | 3:7a284390b0ce | 249 | if((*pInT2 > 0.0f ? *pInT2: -*pInT2) == maxC) |
| emilmont | 1:fdd22bb7aa52 | 250 | { |
| emilmont | 1:fdd22bb7aa52 | 251 | /* Loop over number of columns |
| emilmont | 1:fdd22bb7aa52 | 252 | * to the right of the pilot element */ |
| emilmont | 1:fdd22bb7aa52 | 253 | j = numCols - l; |
| emilmont | 1:fdd22bb7aa52 | 254 | |
| emilmont | 1:fdd22bb7aa52 | 255 | while(j > 0u) |
| emilmont | 1:fdd22bb7aa52 | 256 | { |
| emilmont | 1:fdd22bb7aa52 | 257 | /* Exchange the row elements of the input matrix */ |
| emilmont | 1:fdd22bb7aa52 | 258 | Xchg = *pInT2; |
| emilmont | 1:fdd22bb7aa52 | 259 | *pInT2++ = *pInT1; |
| emilmont | 1:fdd22bb7aa52 | 260 | *pInT1++ = Xchg; |
| emilmont | 1:fdd22bb7aa52 | 261 | |
| emilmont | 1:fdd22bb7aa52 | 262 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 263 | j--; |
| emilmont | 1:fdd22bb7aa52 | 264 | } |
| emilmont | 1:fdd22bb7aa52 | 265 | |
| emilmont | 1:fdd22bb7aa52 | 266 | /* Loop over number of columns of the destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 267 | j = numCols; |
| emilmont | 1:fdd22bb7aa52 | 268 | |
| emilmont | 1:fdd22bb7aa52 | 269 | while(j > 0u) |
| emilmont | 1:fdd22bb7aa52 | 270 | { |
| emilmont | 1:fdd22bb7aa52 | 271 | /* Exchange the row elements of the destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 272 | Xchg = *pInT4; |
| emilmont | 1:fdd22bb7aa52 | 273 | *pInT4++ = *pInT3; |
| emilmont | 1:fdd22bb7aa52 | 274 | *pInT3++ = Xchg; |
| emilmont | 1:fdd22bb7aa52 | 275 | |
| emilmont | 1:fdd22bb7aa52 | 276 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 277 | j--; |
| emilmont | 1:fdd22bb7aa52 | 278 | } |
| emilmont | 1:fdd22bb7aa52 | 279 | |
| emilmont | 1:fdd22bb7aa52 | 280 | /* Flag to indicate whether exchange is done or not */ |
| emilmont | 1:fdd22bb7aa52 | 281 | flag = 1u; |
| emilmont | 1:fdd22bb7aa52 | 282 | |
| emilmont | 1:fdd22bb7aa52 | 283 | /* Break after exchange is done */ |
| emilmont | 1:fdd22bb7aa52 | 284 | break; |
| emilmont | 1:fdd22bb7aa52 | 285 | } |
| emilmont | 1:fdd22bb7aa52 | 286 | |
| emilmont | 1:fdd22bb7aa52 | 287 | /* Update the destination pointer modifier */ |
| emilmont | 1:fdd22bb7aa52 | 288 | k++; |
| emilmont | 1:fdd22bb7aa52 | 289 | |
| emilmont | 1:fdd22bb7aa52 | 290 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 291 | i--; |
| emilmont | 1:fdd22bb7aa52 | 292 | } |
| emilmont | 1:fdd22bb7aa52 | 293 | } |
| emilmont | 1:fdd22bb7aa52 | 294 | |
| emilmont | 1:fdd22bb7aa52 | 295 | /* Update the status if the matrix is singular */ |
| emilmont | 1:fdd22bb7aa52 | 296 | if((flag != 1u) && (in == 0.0f)) |
| emilmont | 1:fdd22bb7aa52 | 297 | { |
| emilmont | 1:fdd22bb7aa52 | 298 | status = ARM_MATH_SINGULAR; |
| emilmont | 1:fdd22bb7aa52 | 299 | |
| emilmont | 1:fdd22bb7aa52 | 300 | break; |
| emilmont | 1:fdd22bb7aa52 | 301 | } |
| emilmont | 1:fdd22bb7aa52 | 302 | |
| emilmont | 1:fdd22bb7aa52 | 303 | /* Points to the pivot row of input and destination matrices */ |
| emilmont | 1:fdd22bb7aa52 | 304 | pPivotRowIn = pIn + (l * numCols); |
| emilmont | 1:fdd22bb7aa52 | 305 | pPivotRowDst = pOut + (l * numCols); |
| emilmont | 1:fdd22bb7aa52 | 306 | |
| emilmont | 1:fdd22bb7aa52 | 307 | /* Temporary pointers to the pivot row pointers */ |
| emilmont | 1:fdd22bb7aa52 | 308 | pInT1 = pPivotRowIn; |
| emilmont | 1:fdd22bb7aa52 | 309 | pInT2 = pPivotRowDst; |
| emilmont | 1:fdd22bb7aa52 | 310 | |
| emilmont | 1:fdd22bb7aa52 | 311 | /* Pivot element of the row */ |
| mbed_official | 3:7a284390b0ce | 312 | in = *pPivotRowIn; |
| emilmont | 1:fdd22bb7aa52 | 313 | |
| emilmont | 1:fdd22bb7aa52 | 314 | /* Loop over number of columns |
| emilmont | 1:fdd22bb7aa52 | 315 | * to the right of the pilot element */ |
| emilmont | 1:fdd22bb7aa52 | 316 | j = (numCols - l); |
| emilmont | 1:fdd22bb7aa52 | 317 | |
| emilmont | 1:fdd22bb7aa52 | 318 | while(j > 0u) |
| emilmont | 1:fdd22bb7aa52 | 319 | { |
| emilmont | 1:fdd22bb7aa52 | 320 | /* Divide each element of the row of the input matrix |
| emilmont | 1:fdd22bb7aa52 | 321 | * by the pivot element */ |
| emilmont | 1:fdd22bb7aa52 | 322 | in1 = *pInT1; |
| emilmont | 1:fdd22bb7aa52 | 323 | *pInT1++ = in1 / in; |
| emilmont | 1:fdd22bb7aa52 | 324 | |
| emilmont | 1:fdd22bb7aa52 | 325 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 326 | j--; |
| emilmont | 1:fdd22bb7aa52 | 327 | } |
| emilmont | 1:fdd22bb7aa52 | 328 | |
| emilmont | 1:fdd22bb7aa52 | 329 | /* Loop over number of columns of the destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 330 | j = numCols; |
| emilmont | 1:fdd22bb7aa52 | 331 | |
| emilmont | 1:fdd22bb7aa52 | 332 | while(j > 0u) |
| emilmont | 1:fdd22bb7aa52 | 333 | { |
| emilmont | 1:fdd22bb7aa52 | 334 | /* Divide each element of the row of the destination matrix |
| emilmont | 1:fdd22bb7aa52 | 335 | * by the pivot element */ |
| emilmont | 1:fdd22bb7aa52 | 336 | in1 = *pInT2; |
| emilmont | 1:fdd22bb7aa52 | 337 | *pInT2++ = in1 / in; |
| emilmont | 1:fdd22bb7aa52 | 338 | |
| emilmont | 1:fdd22bb7aa52 | 339 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 340 | j--; |
| emilmont | 1:fdd22bb7aa52 | 341 | } |
| emilmont | 1:fdd22bb7aa52 | 342 | |
| emilmont | 1:fdd22bb7aa52 | 343 | /* Replace the rows with the sum of that row and a multiple of row i |
| emilmont | 1:fdd22bb7aa52 | 344 | * so that each new element in column i above row i is zero.*/ |
| emilmont | 1:fdd22bb7aa52 | 345 | |
| emilmont | 1:fdd22bb7aa52 | 346 | /* Temporary pointers for input and destination matrices */ |
| emilmont | 1:fdd22bb7aa52 | 347 | pInT1 = pIn; |
| emilmont | 1:fdd22bb7aa52 | 348 | pInT2 = pOut; |
| emilmont | 1:fdd22bb7aa52 | 349 | |
| emilmont | 1:fdd22bb7aa52 | 350 | /* index used to check for pivot element */ |
| emilmont | 1:fdd22bb7aa52 | 351 | i = 0u; |
| emilmont | 1:fdd22bb7aa52 | 352 | |
| emilmont | 1:fdd22bb7aa52 | 353 | /* Loop over number of rows */ |
| emilmont | 1:fdd22bb7aa52 | 354 | /* to be replaced by the sum of that row and a multiple of row i */ |
| emilmont | 1:fdd22bb7aa52 | 355 | k = numRows; |
| emilmont | 1:fdd22bb7aa52 | 356 | |
| emilmont | 1:fdd22bb7aa52 | 357 | while(k > 0u) |
| emilmont | 1:fdd22bb7aa52 | 358 | { |
| emilmont | 1:fdd22bb7aa52 | 359 | /* Check for the pivot element */ |
| emilmont | 1:fdd22bb7aa52 | 360 | if(i == l) |
| emilmont | 1:fdd22bb7aa52 | 361 | { |
| emilmont | 1:fdd22bb7aa52 | 362 | /* If the processing element is the pivot element, |
| emilmont | 1:fdd22bb7aa52 | 363 | only the columns to the right are to be processed */ |
| emilmont | 1:fdd22bb7aa52 | 364 | pInT1 += numCols - l; |
| emilmont | 1:fdd22bb7aa52 | 365 | |
| emilmont | 1:fdd22bb7aa52 | 366 | pInT2 += numCols; |
| emilmont | 1:fdd22bb7aa52 | 367 | } |
| emilmont | 1:fdd22bb7aa52 | 368 | else |
| emilmont | 1:fdd22bb7aa52 | 369 | { |
| emilmont | 1:fdd22bb7aa52 | 370 | /* Element of the reference row */ |
| emilmont | 1:fdd22bb7aa52 | 371 | in = *pInT1; |
| emilmont | 1:fdd22bb7aa52 | 372 | |
| emilmont | 1:fdd22bb7aa52 | 373 | /* Working pointers for input and destination pivot rows */ |
| emilmont | 1:fdd22bb7aa52 | 374 | pPRT_in = pPivotRowIn; |
| emilmont | 1:fdd22bb7aa52 | 375 | pPRT_pDst = pPivotRowDst; |
| emilmont | 1:fdd22bb7aa52 | 376 | |
| emilmont | 1:fdd22bb7aa52 | 377 | /* Loop over the number of columns to the right of the pivot element, |
| emilmont | 1:fdd22bb7aa52 | 378 | to replace the elements in the input matrix */ |
| emilmont | 1:fdd22bb7aa52 | 379 | j = (numCols - l); |
| emilmont | 1:fdd22bb7aa52 | 380 | |
| emilmont | 1:fdd22bb7aa52 | 381 | while(j > 0u) |
| emilmont | 1:fdd22bb7aa52 | 382 | { |
| emilmont | 1:fdd22bb7aa52 | 383 | /* Replace the element by the sum of that row |
| emilmont | 1:fdd22bb7aa52 | 384 | and a multiple of the reference row */ |
| emilmont | 1:fdd22bb7aa52 | 385 | in1 = *pInT1; |
| emilmont | 1:fdd22bb7aa52 | 386 | *pInT1++ = in1 - (in * *pPRT_in++); |
| emilmont | 1:fdd22bb7aa52 | 387 | |
| emilmont | 1:fdd22bb7aa52 | 388 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 389 | j--; |
| emilmont | 1:fdd22bb7aa52 | 390 | } |
| emilmont | 1:fdd22bb7aa52 | 391 | |
| emilmont | 1:fdd22bb7aa52 | 392 | /* Loop over the number of columns to |
| emilmont | 1:fdd22bb7aa52 | 393 | replace the elements in the destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 394 | j = numCols; |
| emilmont | 1:fdd22bb7aa52 | 395 | |
| emilmont | 1:fdd22bb7aa52 | 396 | while(j > 0u) |
| emilmont | 1:fdd22bb7aa52 | 397 | { |
| emilmont | 1:fdd22bb7aa52 | 398 | /* Replace the element by the sum of that row |
| emilmont | 1:fdd22bb7aa52 | 399 | and a multiple of the reference row */ |
| emilmont | 1:fdd22bb7aa52 | 400 | in1 = *pInT2; |
| emilmont | 1:fdd22bb7aa52 | 401 | *pInT2++ = in1 - (in * *pPRT_pDst++); |
| emilmont | 1:fdd22bb7aa52 | 402 | |
| emilmont | 1:fdd22bb7aa52 | 403 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 404 | j--; |
| emilmont | 1:fdd22bb7aa52 | 405 | } |
| emilmont | 1:fdd22bb7aa52 | 406 | |
| emilmont | 1:fdd22bb7aa52 | 407 | } |
| emilmont | 1:fdd22bb7aa52 | 408 | |
| emilmont | 1:fdd22bb7aa52 | 409 | /* Increment the temporary input pointer */ |
| emilmont | 1:fdd22bb7aa52 | 410 | pInT1 = pInT1 + l; |
| emilmont | 1:fdd22bb7aa52 | 411 | |
| emilmont | 1:fdd22bb7aa52 | 412 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 413 | k--; |
| emilmont | 1:fdd22bb7aa52 | 414 | |
| emilmont | 1:fdd22bb7aa52 | 415 | /* Increment the pivot index */ |
| emilmont | 1:fdd22bb7aa52 | 416 | i++; |
| emilmont | 1:fdd22bb7aa52 | 417 | } |
| emilmont | 1:fdd22bb7aa52 | 418 | |
| emilmont | 1:fdd22bb7aa52 | 419 | /* Increment the input pointer */ |
| emilmont | 1:fdd22bb7aa52 | 420 | pIn++; |
| emilmont | 1:fdd22bb7aa52 | 421 | |
| emilmont | 1:fdd22bb7aa52 | 422 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 423 | loopCnt--; |
| emilmont | 1:fdd22bb7aa52 | 424 | |
| emilmont | 1:fdd22bb7aa52 | 425 | /* Increment the index modifier */ |
| emilmont | 1:fdd22bb7aa52 | 426 | l++; |
| emilmont | 1:fdd22bb7aa52 | 427 | } |
| emilmont | 1:fdd22bb7aa52 | 428 | |
| emilmont | 1:fdd22bb7aa52 | 429 | |
| emilmont | 1:fdd22bb7aa52 | 430 | #else |
| emilmont | 1:fdd22bb7aa52 | 431 | |
| emilmont | 1:fdd22bb7aa52 | 432 | /* Run the below code for Cortex-M0 */ |
| emilmont | 1:fdd22bb7aa52 | 433 | |
| emilmont | 1:fdd22bb7aa52 | 434 | float32_t Xchg, in = 0.0f; /* Temporary input values */ |
| emilmont | 1:fdd22bb7aa52 | 435 | uint32_t i, rowCnt, flag = 0u, j, loopCnt, k, l; /* loop counters */ |
| emilmont | 1:fdd22bb7aa52 | 436 | arm_status status; /* status of matrix inverse */ |
| emilmont | 1:fdd22bb7aa52 | 437 | |
| emilmont | 1:fdd22bb7aa52 | 438 | #ifdef ARM_MATH_MATRIX_CHECK |
| emilmont | 1:fdd22bb7aa52 | 439 | |
| emilmont | 1:fdd22bb7aa52 | 440 | /* Check for matrix mismatch condition */ |
| emilmont | 1:fdd22bb7aa52 | 441 | if((pSrc->numRows != pSrc->numCols) || (pDst->numRows != pDst->numCols) |
| emilmont | 1:fdd22bb7aa52 | 442 | || (pSrc->numRows != pDst->numRows)) |
| emilmont | 1:fdd22bb7aa52 | 443 | { |
| emilmont | 1:fdd22bb7aa52 | 444 | /* Set status as ARM_MATH_SIZE_MISMATCH */ |
| emilmont | 1:fdd22bb7aa52 | 445 | status = ARM_MATH_SIZE_MISMATCH; |
| emilmont | 1:fdd22bb7aa52 | 446 | } |
| emilmont | 1:fdd22bb7aa52 | 447 | else |
| emilmont | 1:fdd22bb7aa52 | 448 | #endif /* #ifdef ARM_MATH_MATRIX_CHECK */ |
| emilmont | 1:fdd22bb7aa52 | 449 | { |
| emilmont | 1:fdd22bb7aa52 | 450 | |
| emilmont | 1:fdd22bb7aa52 | 451 | /*-------------------------------------------------------------------------------------------------------------- |
| emilmont | 2:da51fb522205 | 452 | * Matrix Inverse can be solved using elementary row operations. |
| emilmont | 2:da51fb522205 | 453 | * |
| emilmont | 2:da51fb522205 | 454 | * Gauss-Jordan Method: |
| emilmont | 2:da51fb522205 | 455 | * |
| emilmont | 2:da51fb522205 | 456 | * 1. First combine the identity matrix and the input matrix separated by a bar to form an |
| emilmont | 2:da51fb522205 | 457 | * augmented matrix as follows: |
| emilmont | 2:da51fb522205 | 458 | * _ _ _ _ _ _ _ _ |
| emilmont | 2:da51fb522205 | 459 | * | | a11 a12 | | | 1 0 | | | X11 X12 | |
| emilmont | 2:da51fb522205 | 460 | * | | | | | | | = | | |
| emilmont | 2:da51fb522205 | 461 | * |_ |_ a21 a22 _| | |_0 1 _| _| |_ X21 X21 _| |
| emilmont | 2:da51fb522205 | 462 | * |
| emilmont | 2:da51fb522205 | 463 | * 2. In our implementation, pDst Matrix is used as identity matrix. |
| emilmont | 2:da51fb522205 | 464 | * |
| emilmont | 2:da51fb522205 | 465 | * 3. Begin with the first row. Let i = 1. |
| emilmont | 2:da51fb522205 | 466 | * |
| emilmont | 2:da51fb522205 | 467 | * 4. Check to see if the pivot for row i is zero. |
| emilmont | 2:da51fb522205 | 468 | * The pivot is the element of the main diagonal that is on the current row. |
| emilmont | 2:da51fb522205 | 469 | * For instance, if working with row i, then the pivot element is aii. |
| emilmont | 2:da51fb522205 | 470 | * If the pivot is zero, exchange that row with a row below it that does not |
| emilmont | 2:da51fb522205 | 471 | * contain a zero in column i. If this is not possible, then an inverse |
| emilmont | 2:da51fb522205 | 472 | * to that matrix does not exist. |
| emilmont | 2:da51fb522205 | 473 | * |
| emilmont | 2:da51fb522205 | 474 | * 5. Divide every element of row i by the pivot. |
| emilmont | 2:da51fb522205 | 475 | * |
| emilmont | 2:da51fb522205 | 476 | * 6. For every row below and row i, replace that row with the sum of that row and |
| emilmont | 2:da51fb522205 | 477 | * a multiple of row i so that each new element in column i below row i is zero. |
| emilmont | 2:da51fb522205 | 478 | * |
| emilmont | 2:da51fb522205 | 479 | * 7. Move to the next row and column and repeat steps 2 through 5 until you have zeros |
| emilmont | 2:da51fb522205 | 480 | * for every element below and above the main diagonal. |
| emilmont | 2:da51fb522205 | 481 | * |
| emilmont | 2:da51fb522205 | 482 | * 8. Now an identical matrix is formed to the left of the bar(input matrix, src). |
| emilmont | 2:da51fb522205 | 483 | * Therefore, the matrix to the right of the bar is our solution(dst matrix, dst). |
| emilmont | 2:da51fb522205 | 484 | *----------------------------------------------------------------------------------------------------------------*/ |
| emilmont | 1:fdd22bb7aa52 | 485 | |
| emilmont | 1:fdd22bb7aa52 | 486 | /* Working pointer for destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 487 | pInT2 = pOut; |
| emilmont | 1:fdd22bb7aa52 | 488 | |
| emilmont | 1:fdd22bb7aa52 | 489 | /* Loop over the number of rows */ |
| emilmont | 1:fdd22bb7aa52 | 490 | rowCnt = numRows; |
| emilmont | 1:fdd22bb7aa52 | 491 | |
| emilmont | 1:fdd22bb7aa52 | 492 | /* Making the destination matrix as identity matrix */ |
| emilmont | 1:fdd22bb7aa52 | 493 | while(rowCnt > 0u) |
| emilmont | 1:fdd22bb7aa52 | 494 | { |
| emilmont | 1:fdd22bb7aa52 | 495 | /* Writing all zeroes in lower triangle of the destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 496 | j = numRows - rowCnt; |
| emilmont | 1:fdd22bb7aa52 | 497 | while(j > 0u) |
| emilmont | 1:fdd22bb7aa52 | 498 | { |
| emilmont | 1:fdd22bb7aa52 | 499 | *pInT2++ = 0.0f; |
| emilmont | 1:fdd22bb7aa52 | 500 | j--; |
| emilmont | 1:fdd22bb7aa52 | 501 | } |
| emilmont | 1:fdd22bb7aa52 | 502 | |
| emilmont | 1:fdd22bb7aa52 | 503 | /* Writing all ones in the diagonal of the destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 504 | *pInT2++ = 1.0f; |
| emilmont | 1:fdd22bb7aa52 | 505 | |
| emilmont | 1:fdd22bb7aa52 | 506 | /* Writing all zeroes in upper triangle of the destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 507 | j = rowCnt - 1u; |
| emilmont | 1:fdd22bb7aa52 | 508 | while(j > 0u) |
| emilmont | 1:fdd22bb7aa52 | 509 | { |
| emilmont | 1:fdd22bb7aa52 | 510 | *pInT2++ = 0.0f; |
| emilmont | 1:fdd22bb7aa52 | 511 | j--; |
| emilmont | 1:fdd22bb7aa52 | 512 | } |
| emilmont | 1:fdd22bb7aa52 | 513 | |
| emilmont | 1:fdd22bb7aa52 | 514 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 515 | rowCnt--; |
| emilmont | 1:fdd22bb7aa52 | 516 | } |
| emilmont | 1:fdd22bb7aa52 | 517 | |
| emilmont | 1:fdd22bb7aa52 | 518 | /* Loop over the number of columns of the input matrix. |
| emilmont | 1:fdd22bb7aa52 | 519 | All the elements in each column are processed by the row operations */ |
| emilmont | 1:fdd22bb7aa52 | 520 | loopCnt = numCols; |
| emilmont | 1:fdd22bb7aa52 | 521 | |
| emilmont | 1:fdd22bb7aa52 | 522 | /* Index modifier to navigate through the columns */ |
| emilmont | 1:fdd22bb7aa52 | 523 | l = 0u; |
| emilmont | 1:fdd22bb7aa52 | 524 | //for(loopCnt = 0u; loopCnt < numCols; loopCnt++) |
| emilmont | 1:fdd22bb7aa52 | 525 | while(loopCnt > 0u) |
| emilmont | 1:fdd22bb7aa52 | 526 | { |
| emilmont | 1:fdd22bb7aa52 | 527 | /* Check if the pivot element is zero.. |
| emilmont | 1:fdd22bb7aa52 | 528 | * If it is zero then interchange the row with non zero row below. |
| emilmont | 1:fdd22bb7aa52 | 529 | * If there is no non zero element to replace in the rows below, |
| emilmont | 1:fdd22bb7aa52 | 530 | * then the matrix is Singular. */ |
| emilmont | 1:fdd22bb7aa52 | 531 | |
| emilmont | 1:fdd22bb7aa52 | 532 | /* Working pointer for the input matrix that points |
| emilmont | 1:fdd22bb7aa52 | 533 | * to the pivot element of the particular row */ |
| emilmont | 1:fdd22bb7aa52 | 534 | pInT1 = pIn + (l * numCols); |
| emilmont | 1:fdd22bb7aa52 | 535 | |
| emilmont | 1:fdd22bb7aa52 | 536 | /* Working pointer for the destination matrix that points |
| emilmont | 1:fdd22bb7aa52 | 537 | * to the pivot element of the particular row */ |
| emilmont | 1:fdd22bb7aa52 | 538 | pInT3 = pOut + (l * numCols); |
| emilmont | 1:fdd22bb7aa52 | 539 | |
| emilmont | 1:fdd22bb7aa52 | 540 | /* Temporary variable to hold the pivot value */ |
| emilmont | 1:fdd22bb7aa52 | 541 | in = *pInT1; |
| emilmont | 1:fdd22bb7aa52 | 542 | |
| emilmont | 1:fdd22bb7aa52 | 543 | /* Destination pointer modifier */ |
| emilmont | 1:fdd22bb7aa52 | 544 | k = 1u; |
| emilmont | 1:fdd22bb7aa52 | 545 | |
| emilmont | 1:fdd22bb7aa52 | 546 | /* Check if the pivot element is zero */ |
| emilmont | 1:fdd22bb7aa52 | 547 | if(*pInT1 == 0.0f) |
| emilmont | 1:fdd22bb7aa52 | 548 | { |
| emilmont | 1:fdd22bb7aa52 | 549 | /* Loop over the number rows present below */ |
| emilmont | 1:fdd22bb7aa52 | 550 | for (i = (l + 1u); i < numRows; i++) |
| emilmont | 1:fdd22bb7aa52 | 551 | { |
| emilmont | 1:fdd22bb7aa52 | 552 | /* Update the input and destination pointers */ |
| emilmont | 1:fdd22bb7aa52 | 553 | pInT2 = pInT1 + (numCols * l); |
| emilmont | 1:fdd22bb7aa52 | 554 | pInT4 = pInT3 + (numCols * k); |
| emilmont | 1:fdd22bb7aa52 | 555 | |
| emilmont | 1:fdd22bb7aa52 | 556 | /* Check if there is a non zero pivot element to |
| emilmont | 1:fdd22bb7aa52 | 557 | * replace in the rows below */ |
| emilmont | 1:fdd22bb7aa52 | 558 | if(*pInT2 != 0.0f) |
| emilmont | 1:fdd22bb7aa52 | 559 | { |
| emilmont | 1:fdd22bb7aa52 | 560 | /* Loop over number of columns |
| emilmont | 1:fdd22bb7aa52 | 561 | * to the right of the pilot element */ |
| emilmont | 1:fdd22bb7aa52 | 562 | for (j = 0u; j < (numCols - l); j++) |
| emilmont | 1:fdd22bb7aa52 | 563 | { |
| emilmont | 1:fdd22bb7aa52 | 564 | /* Exchange the row elements of the input matrix */ |
| emilmont | 1:fdd22bb7aa52 | 565 | Xchg = *pInT2; |
| emilmont | 1:fdd22bb7aa52 | 566 | *pInT2++ = *pInT1; |
| emilmont | 1:fdd22bb7aa52 | 567 | *pInT1++ = Xchg; |
| emilmont | 1:fdd22bb7aa52 | 568 | } |
| emilmont | 1:fdd22bb7aa52 | 569 | |
| emilmont | 1:fdd22bb7aa52 | 570 | for (j = 0u; j < numCols; j++) |
| emilmont | 1:fdd22bb7aa52 | 571 | { |
| emilmont | 1:fdd22bb7aa52 | 572 | Xchg = *pInT4; |
| emilmont | 1:fdd22bb7aa52 | 573 | *pInT4++ = *pInT3; |
| emilmont | 1:fdd22bb7aa52 | 574 | *pInT3++ = Xchg; |
| emilmont | 1:fdd22bb7aa52 | 575 | } |
| emilmont | 1:fdd22bb7aa52 | 576 | |
| emilmont | 1:fdd22bb7aa52 | 577 | /* Flag to indicate whether exchange is done or not */ |
| emilmont | 1:fdd22bb7aa52 | 578 | flag = 1u; |
| emilmont | 1:fdd22bb7aa52 | 579 | |
| emilmont | 1:fdd22bb7aa52 | 580 | /* Break after exchange is done */ |
| emilmont | 1:fdd22bb7aa52 | 581 | break; |
| emilmont | 1:fdd22bb7aa52 | 582 | } |
| emilmont | 1:fdd22bb7aa52 | 583 | |
| emilmont | 1:fdd22bb7aa52 | 584 | /* Update the destination pointer modifier */ |
| emilmont | 1:fdd22bb7aa52 | 585 | k++; |
| emilmont | 1:fdd22bb7aa52 | 586 | } |
| emilmont | 1:fdd22bb7aa52 | 587 | } |
| emilmont | 1:fdd22bb7aa52 | 588 | |
| emilmont | 1:fdd22bb7aa52 | 589 | /* Update the status if the matrix is singular */ |
| emilmont | 1:fdd22bb7aa52 | 590 | if((flag != 1u) && (in == 0.0f)) |
| emilmont | 1:fdd22bb7aa52 | 591 | { |
| emilmont | 1:fdd22bb7aa52 | 592 | status = ARM_MATH_SINGULAR; |
| emilmont | 1:fdd22bb7aa52 | 593 | |
| emilmont | 1:fdd22bb7aa52 | 594 | break; |
| emilmont | 1:fdd22bb7aa52 | 595 | } |
| emilmont | 1:fdd22bb7aa52 | 596 | |
| emilmont | 1:fdd22bb7aa52 | 597 | /* Points to the pivot row of input and destination matrices */ |
| emilmont | 1:fdd22bb7aa52 | 598 | pPivotRowIn = pIn + (l * numCols); |
| emilmont | 1:fdd22bb7aa52 | 599 | pPivotRowDst = pOut + (l * numCols); |
| emilmont | 1:fdd22bb7aa52 | 600 | |
| emilmont | 1:fdd22bb7aa52 | 601 | /* Temporary pointers to the pivot row pointers */ |
| emilmont | 1:fdd22bb7aa52 | 602 | pInT1 = pPivotRowIn; |
| emilmont | 1:fdd22bb7aa52 | 603 | pInT2 = pPivotRowDst; |
| emilmont | 1:fdd22bb7aa52 | 604 | |
| emilmont | 1:fdd22bb7aa52 | 605 | /* Pivot element of the row */ |
| emilmont | 1:fdd22bb7aa52 | 606 | in = *(pIn + (l * numCols)); |
| emilmont | 1:fdd22bb7aa52 | 607 | |
| emilmont | 1:fdd22bb7aa52 | 608 | /* Loop over number of columns |
| emilmont | 1:fdd22bb7aa52 | 609 | * to the right of the pilot element */ |
| emilmont | 1:fdd22bb7aa52 | 610 | for (j = 0u; j < (numCols - l); j++) |
| emilmont | 1:fdd22bb7aa52 | 611 | { |
| emilmont | 1:fdd22bb7aa52 | 612 | /* Divide each element of the row of the input matrix |
| emilmont | 1:fdd22bb7aa52 | 613 | * by the pivot element */ |
| mbed_official | 3:7a284390b0ce | 614 | *pInT1 = *pInT1 / in; |
| mbed_official | 3:7a284390b0ce | 615 | pInT1++; |
| emilmont | 1:fdd22bb7aa52 | 616 | } |
| emilmont | 1:fdd22bb7aa52 | 617 | for (j = 0u; j < numCols; j++) |
| emilmont | 1:fdd22bb7aa52 | 618 | { |
| emilmont | 1:fdd22bb7aa52 | 619 | /* Divide each element of the row of the destination matrix |
| emilmont | 1:fdd22bb7aa52 | 620 | * by the pivot element */ |
| mbed_official | 3:7a284390b0ce | 621 | *pInT2 = *pInT2 / in; |
| mbed_official | 3:7a284390b0ce | 622 | pInT2++; |
| emilmont | 1:fdd22bb7aa52 | 623 | } |
| emilmont | 1:fdd22bb7aa52 | 624 | |
| emilmont | 1:fdd22bb7aa52 | 625 | /* Replace the rows with the sum of that row and a multiple of row i |
| emilmont | 1:fdd22bb7aa52 | 626 | * so that each new element in column i above row i is zero.*/ |
| emilmont | 1:fdd22bb7aa52 | 627 | |
| emilmont | 1:fdd22bb7aa52 | 628 | /* Temporary pointers for input and destination matrices */ |
| emilmont | 1:fdd22bb7aa52 | 629 | pInT1 = pIn; |
| emilmont | 1:fdd22bb7aa52 | 630 | pInT2 = pOut; |
| emilmont | 1:fdd22bb7aa52 | 631 | |
| emilmont | 1:fdd22bb7aa52 | 632 | for (i = 0u; i < numRows; i++) |
| emilmont | 1:fdd22bb7aa52 | 633 | { |
| emilmont | 1:fdd22bb7aa52 | 634 | /* Check for the pivot element */ |
| emilmont | 1:fdd22bb7aa52 | 635 | if(i == l) |
| emilmont | 1:fdd22bb7aa52 | 636 | { |
| emilmont | 1:fdd22bb7aa52 | 637 | /* If the processing element is the pivot element, |
| emilmont | 1:fdd22bb7aa52 | 638 | only the columns to the right are to be processed */ |
| emilmont | 1:fdd22bb7aa52 | 639 | pInT1 += numCols - l; |
| emilmont | 1:fdd22bb7aa52 | 640 | pInT2 += numCols; |
| emilmont | 1:fdd22bb7aa52 | 641 | } |
| emilmont | 1:fdd22bb7aa52 | 642 | else |
| emilmont | 1:fdd22bb7aa52 | 643 | { |
| emilmont | 1:fdd22bb7aa52 | 644 | /* Element of the reference row */ |
| emilmont | 1:fdd22bb7aa52 | 645 | in = *pInT1; |
| emilmont | 1:fdd22bb7aa52 | 646 | |
| emilmont | 1:fdd22bb7aa52 | 647 | /* Working pointers for input and destination pivot rows */ |
| emilmont | 1:fdd22bb7aa52 | 648 | pPRT_in = pPivotRowIn; |
| emilmont | 1:fdd22bb7aa52 | 649 | pPRT_pDst = pPivotRowDst; |
| emilmont | 1:fdd22bb7aa52 | 650 | |
| emilmont | 1:fdd22bb7aa52 | 651 | /* Loop over the number of columns to the right of the pivot element, |
| emilmont | 1:fdd22bb7aa52 | 652 | to replace the elements in the input matrix */ |
| emilmont | 1:fdd22bb7aa52 | 653 | for (j = 0u; j < (numCols - l); j++) |
| emilmont | 1:fdd22bb7aa52 | 654 | { |
| emilmont | 1:fdd22bb7aa52 | 655 | /* Replace the element by the sum of that row |
| emilmont | 1:fdd22bb7aa52 | 656 | and a multiple of the reference row */ |
| mbed_official | 3:7a284390b0ce | 657 | *pInT1 = *pInT1 - (in * *pPRT_in++); |
| mbed_official | 3:7a284390b0ce | 658 | pInT1++; |
| emilmont | 1:fdd22bb7aa52 | 659 | } |
| emilmont | 1:fdd22bb7aa52 | 660 | /* Loop over the number of columns to |
| emilmont | 1:fdd22bb7aa52 | 661 | replace the elements in the destination matrix */ |
| emilmont | 1:fdd22bb7aa52 | 662 | for (j = 0u; j < numCols; j++) |
| emilmont | 1:fdd22bb7aa52 | 663 | { |
| emilmont | 1:fdd22bb7aa52 | 664 | /* Replace the element by the sum of that row |
| emilmont | 1:fdd22bb7aa52 | 665 | and a multiple of the reference row */ |
| mbed_official | 3:7a284390b0ce | 666 | *pInT2 = *pInT2 - (in * *pPRT_pDst++); |
| mbed_official | 3:7a284390b0ce | 667 | pInT2++; |
| emilmont | 1:fdd22bb7aa52 | 668 | } |
| emilmont | 1:fdd22bb7aa52 | 669 | |
| emilmont | 1:fdd22bb7aa52 | 670 | } |
| emilmont | 1:fdd22bb7aa52 | 671 | /* Increment the temporary input pointer */ |
| emilmont | 1:fdd22bb7aa52 | 672 | pInT1 = pInT1 + l; |
| emilmont | 1:fdd22bb7aa52 | 673 | } |
| emilmont | 1:fdd22bb7aa52 | 674 | /* Increment the input pointer */ |
| emilmont | 1:fdd22bb7aa52 | 675 | pIn++; |
| emilmont | 1:fdd22bb7aa52 | 676 | |
| emilmont | 1:fdd22bb7aa52 | 677 | /* Decrement the loop counter */ |
| emilmont | 1:fdd22bb7aa52 | 678 | loopCnt--; |
| emilmont | 1:fdd22bb7aa52 | 679 | /* Increment the index modifier */ |
| emilmont | 1:fdd22bb7aa52 | 680 | l++; |
| emilmont | 1:fdd22bb7aa52 | 681 | } |
| emilmont | 1:fdd22bb7aa52 | 682 | |
| emilmont | 1:fdd22bb7aa52 | 683 | |
| mbed_official | 3:7a284390b0ce | 684 | #endif /* #ifndef ARM_MATH_CM0_FAMILY */ |
| emilmont | 1:fdd22bb7aa52 | 685 | |
| emilmont | 1:fdd22bb7aa52 | 686 | /* Set status as ARM_MATH_SUCCESS */ |
| emilmont | 1:fdd22bb7aa52 | 687 | status = ARM_MATH_SUCCESS; |
| emilmont | 1:fdd22bb7aa52 | 688 | |
| emilmont | 1:fdd22bb7aa52 | 689 | if((flag != 1u) && (in == 0.0f)) |
| emilmont | 1:fdd22bb7aa52 | 690 | { |
| emilmont | 1:fdd22bb7aa52 | 691 | status = ARM_MATH_SINGULAR; |
| emilmont | 1:fdd22bb7aa52 | 692 | } |
| emilmont | 1:fdd22bb7aa52 | 693 | } |
| emilmont | 1:fdd22bb7aa52 | 694 | /* Return to application */ |
| emilmont | 1:fdd22bb7aa52 | 695 | return (status); |
| emilmont | 1:fdd22bb7aa52 | 696 | } |
| emilmont | 1:fdd22bb7aa52 | 697 | |
| emilmont | 1:fdd22bb7aa52 | 698 | /** |
| emilmont | 1:fdd22bb7aa52 | 699 | * @} end of MatrixInv group |
| emilmont | 1:fdd22bb7aa52 | 700 | */ |