| 1 | tim | 891 | /* | 
| 2 |  |  | * Copyright (c) 2005 The University of Notre Dame. All Rights Reserved. | 
| 3 |  |  | * | 
| 4 |  |  | * The University of Notre Dame grants you ("Licensee") a | 
| 5 |  |  | * non-exclusive, royalty free, license to use, modify and | 
| 6 |  |  | * redistribute this software in source and binary code form, provided | 
| 7 |  |  | * that the following conditions are met: | 
| 8 |  |  | * | 
| 9 |  |  | * 1. Acknowledgement of the program authors must be made in any | 
| 10 |  |  | *    publication of scientific results based in part on use of the | 
| 11 |  |  | *    program.  An acceptable form of acknowledgement is citation of | 
| 12 |  |  | *    the article in which the program was described (Matthew | 
| 13 |  |  | *    A. Meineke, Charles F. Vardeman II, Teng Lin, Christopher | 
| 14 |  |  | *    J. Fennell and J. Daniel Gezelter, "OOPSE: An Object-Oriented | 
| 15 |  |  | *    Parallel Simulation Engine for Molecular Dynamics," | 
| 16 |  |  | *    J. Comput. Chem. 26, pp. 252-271 (2005)) | 
| 17 |  |  | * | 
| 18 |  |  | * 2. Redistributions of source code must retain the above copyright | 
| 19 |  |  | *    notice, this list of conditions and the following disclaimer. | 
| 20 |  |  | * | 
| 21 |  |  | * 3. Redistributions in binary form must reproduce the above copyright | 
| 22 |  |  | *    notice, this list of conditions and the following disclaimer in the | 
| 23 |  |  | *    documentation and/or other materials provided with the | 
| 24 |  |  | *    distribution. | 
| 25 |  |  | * | 
| 26 |  |  | * This software is provided "AS IS," without a warranty of any | 
| 27 |  |  | * kind. All express or implied conditions, representations and | 
| 28 |  |  | * warranties, including any implied warranty of merchantability, | 
| 29 |  |  | * fitness for a particular purpose or non-infringement, are hereby | 
| 30 |  |  | * excluded.  The University of Notre Dame and its licensors shall not | 
| 31 |  |  | * be liable for any damages suffered by licensee as a result of | 
| 32 |  |  | * using, modifying or distributing the software or its | 
| 33 |  |  | * derivatives. In no event will the University of Notre Dame or its | 
| 34 |  |  | * licensors be liable for any lost revenue, profit or data, or for | 
| 35 |  |  | * direct, indirect, special, consequential, incidental or punitive | 
| 36 |  |  | * damages, however caused and regardless of the theory of liability, | 
| 37 |  |  | * arising out of the use of or inability to use software, even if the | 
| 38 |  |  | * University of Notre Dame has been advised of the possibility of | 
| 39 |  |  | * such damages. | 
| 40 |  |  | */ | 
| 41 |  |  |  | 
| 42 |  |  | /*========================================================================= | 
| 43 |  |  |  | 
| 44 |  |  | Program:   Visualization Toolkit | 
| 45 |  |  | Module:    $RCSfile: LU.hpp,v $ | 
| 46 |  |  |  | 
| 47 |  |  | Copyright (c) 1993-2003 Ken Martin, Will Schroeder, Bill Lorensen | 
| 48 |  |  | All rights reserved. | 
| 49 |  |  |  | 
| 50 |  |  | Redistribution and use in source and binary forms, with or without | 
| 51 |  |  | modification, are permitted provided that the following conditions are met: | 
| 52 |  |  |  | 
| 53 |  |  | * Redistributions of source code must retain the above copyright notice, | 
| 54 |  |  | this list of conditions and the following disclaimer. | 
| 55 |  |  |  | 
| 56 |  |  | * Redistributions in binary form must reproduce the above copyright notice, | 
| 57 |  |  | this list of conditions and the following disclaimer in the documentation | 
| 58 |  |  | and/or other materials provided with the distribution. | 
| 59 |  |  |  | 
| 60 |  |  | * Neither name of Ken Martin, Will Schroeder, or Bill Lorensen nor the names | 
| 61 |  |  | of any contributors may be used to endorse or promote products derived | 
| 62 |  |  | from this software without specific prior written permission. | 
| 63 |  |  |  | 
| 64 |  |  | * Modified source versions must be plainly marked as such, and must not be | 
| 65 |  |  | misrepresented as being the original software. | 
| 66 |  |  |  | 
| 67 |  |  | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS ``AS IS'' | 
| 68 |  |  | AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | 
| 69 |  |  | IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | 
| 70 |  |  | ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE FOR | 
| 71 |  |  | ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | 
| 72 |  |  | DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR | 
| 73 |  |  | SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER | 
| 74 |  |  | CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, | 
| 75 |  |  | OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | 
| 76 |  |  | OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | 
| 77 |  |  |  | 
| 78 |  |  | =========================================================================*/ | 
| 79 |  |  | #ifndef MATH_LU_HPP | 
| 80 |  |  | #define MATH_LU_HPP | 
| 81 |  |  |  | 
| 82 |  |  | #include "utils/NumericConstant.hpp" | 
| 83 |  |  |  | 
| 84 |  |  | namespace oopse { | 
| 85 |  |  |  | 
| 86 |  |  | /** | 
| 87 |  |  | * Invert input square matrix A into matrix AI. | 
| 88 |  |  | * @param A input square matrix | 
| 89 |  |  | * @param AI output square matrix | 
| 90 |  |  | * @return true if inverse is computed, otherwise return false | 
| 91 |  |  | * @note A is modified during the inversion | 
| 92 |  |  | */ | 
| 93 |  |  | template<class MatrixType> | 
| 94 |  |  | bool invertMatrix(MatrixType& A, MatrixType& AI) | 
| 95 |  |  | { | 
| 96 |  |  | typedef typename MatrixType::ElemType Real; | 
| 97 |  |  | if (A.getNRow() != A.getNCol() || A.getNRow() != AI.getNRow() || A.getNCol() != AI.getNCol()) { | 
| 98 |  |  | return false; | 
| 99 |  |  | } | 
| 100 |  |  |  | 
| 101 |  |  | int size = A.getNRow(); | 
| 102 |  |  | int *index=NULL, iScratch[10]; | 
| 103 |  |  | Real *column=NULL, dScratch[10]; | 
| 104 |  |  |  | 
| 105 |  |  | // Check on allocation of working vectors | 
| 106 |  |  | // | 
| 107 |  |  | if ( size <= 10 ) { | 
| 108 |  |  | index = iScratch; | 
| 109 |  |  | column = dScratch; | 
| 110 |  |  | } else { | 
| 111 |  |  | index = new int[size]; | 
| 112 |  |  | column = new Real[size]; | 
| 113 |  |  | } | 
| 114 |  |  |  | 
| 115 |  |  | bool retVal = invertMatrix(A, AI, size, index, column); | 
| 116 |  |  |  | 
| 117 |  |  | if ( size > 10 ) { | 
| 118 |  |  | delete [] index; | 
| 119 |  |  | delete [] column; | 
| 120 |  |  | } | 
| 121 |  |  |  | 
| 122 |  |  | return retVal; | 
| 123 |  |  | } | 
| 124 |  |  |  | 
| 125 |  |  | /** | 
| 126 |  |  | * Invert input square matrix A into matrix AI (Thread safe versions). | 
| 127 |  |  | * @param A input square matrix | 
| 128 |  |  | * @param AI output square matrix | 
| 129 |  |  | * @param size size of the matrix and temporary arrays | 
| 130 |  |  | * @param tmp1Size temporary array | 
| 131 |  |  | * @param tmp2Size temporary array | 
| 132 |  |  | * @return true if inverse is computed, otherwise return false | 
| 133 |  |  | * @note A is modified during the inversion. | 
| 134 |  |  | */ | 
| 135 |  |  |  | 
| 136 |  |  | template<class MatrixType> | 
| 137 |  |  | bool invertMatrix(MatrixType& A , MatrixType& AI, int size, | 
| 138 |  |  | int *tmp1Size, typename MatrixType::ElemPoinerType tmp2Size) | 
| 139 |  |  | { | 
| 140 |  |  | if (A.getNRow() != A.getNCol() || A.getNRow() != AI.getNRow() || A.getNCol() != AI.getNCol() || A.getNRow() != size) { | 
| 141 |  |  | return false; | 
| 142 |  |  | } | 
| 143 |  |  |  | 
| 144 |  |  | int i, j; | 
| 145 |  |  |  | 
| 146 |  |  | // | 
| 147 |  |  | // Factor matrix; then begin solving for inverse one column at a time. | 
| 148 |  |  | // Note: tmp1Size returned value is used later, tmp2Size is just working | 
| 149 |  |  | // memory whose values are not used in LUSolveLinearSystem | 
| 150 |  |  | // | 
| 151 |  |  | if ( LUFactorLinearSystem(A, tmp1Size, size, tmp2Size) == 0 ){ | 
| 152 |  |  | return false; | 
| 153 |  |  | } | 
| 154 |  |  |  | 
| 155 |  |  | for ( j=0; j < size; j++ ) { | 
| 156 |  |  | for ( i=0; i < size; i++ ) { | 
| 157 |  |  | tmp2Size[i] = 0.0; | 
| 158 |  |  | } | 
| 159 |  |  | tmp2Size[j] = 1.0; | 
| 160 |  |  |  | 
| 161 |  |  | LUSolveLinearSystem(A,tmp1Size,tmp2Size,size); | 
| 162 |  |  |  | 
| 163 |  |  | for ( i=0; i < size; i++ ) { | 
| 164 |  |  | AI(i, j) = tmp2Size[i]; | 
| 165 |  |  | } | 
| 166 |  |  | } | 
| 167 |  |  |  | 
| 168 |  |  | return true; | 
| 169 |  |  | } | 
| 170 |  |  |  | 
| 171 |  |  | /** | 
| 172 |  |  | * Factor linear equations Ax = b using LU decompostion A = LU where L is | 
| 173 |  |  | * lower triangular matrix and U is upper triangular matrix. | 
| 174 |  |  | * @param A input square matrix | 
| 175 |  |  | * @param index pivot indices | 
| 176 |  |  | * @param size size of the matrix and temporary arrays | 
| 177 |  |  | * @param tmpSize temporary array | 
| 178 |  |  | * @return true if inverse is computed, otherwise return false | 
| 179 |  |  | * @note A is modified during the inversion. | 
| 180 |  |  | */ | 
| 181 |  |  | template<class MatrixType> | 
| 182 |  |  | int LUFactorLinearSystem(MatrixType& A, int *index, int size, | 
| 183 |  |  | typename MatrixType::ElemPoinerType tmpSize) | 
| 184 |  |  | { | 
| 185 |  |  | typedef typename MatrixType::ElemType Real; | 
| 186 |  |  | int i, j, k; | 
| 187 |  |  | int maxI = 0; | 
| 188 |  |  | Real largest, temp1, temp2, sum; | 
| 189 |  |  |  | 
| 190 |  |  | // | 
| 191 |  |  | // Loop over rows to get implicit scaling information | 
| 192 |  |  | // | 
| 193 |  |  | for ( i = 0; i < size; i++ ) { | 
| 194 |  |  | for ( largest = 0.0, j = 0; j < size; j++ ) { | 
| 195 |  |  | if ( (temp2 = fabs(A(i, j))) > largest ) { | 
| 196 |  |  | largest = temp2; | 
| 197 |  |  | } | 
| 198 |  |  | } | 
| 199 |  |  |  | 
| 200 |  |  | if ( largest == 0.0 ) { | 
| 201 |  |  | //vtkGenericWarningMacro(<<"Unable to factor linear system"); | 
| 202 |  |  | return 0; | 
| 203 |  |  | } | 
| 204 |  |  | tmpSize[i] = 1.0 / largest; | 
| 205 |  |  | } | 
| 206 |  |  | // | 
| 207 |  |  | // Loop over all columns using Crout's method | 
| 208 |  |  | // | 
| 209 |  |  | for ( j = 0; j < size; j++ ) { | 
| 210 |  |  | for (i = 0; i < j; i++) { | 
| 211 |  |  | sum = A(i, j); | 
| 212 |  |  | for ( k = 0; k < i; k++ ) { | 
| 213 |  |  | sum -= A(i, k) * A(k, j); | 
| 214 |  |  | } | 
| 215 |  |  | A(i, j) = sum; | 
| 216 |  |  | } | 
| 217 |  |  | // | 
| 218 |  |  | // Begin search for largest pivot element | 
| 219 |  |  | // | 
| 220 |  |  | for ( largest = 0.0, i = j; i < size; i++ ) { | 
| 221 |  |  | sum = A(i, j); | 
| 222 |  |  | for ( k = 0; k < j; k++ ) { | 
| 223 |  |  | sum -= A(i, k) * A(k, j); | 
| 224 |  |  | } | 
| 225 |  |  | A(i, j) = sum; | 
| 226 |  |  |  | 
| 227 |  |  | if ( (temp1 = tmpSize[i]*fabs(sum)) >= largest ) { | 
| 228 |  |  | largest = temp1; | 
| 229 |  |  | maxI = i; | 
| 230 |  |  | } | 
| 231 |  |  | } | 
| 232 |  |  | // | 
| 233 |  |  | // Check for row interchange | 
| 234 |  |  | // | 
| 235 |  |  | if ( j != maxI ) { | 
| 236 |  |  | for ( k = 0; k < size; k++ ) { | 
| 237 |  |  | temp1 = A(maxI, k); | 
| 238 |  |  | A(maxI, k) = A(j, k); | 
| 239 |  |  | A(j, k) = temp1; | 
| 240 |  |  | } | 
| 241 |  |  | tmpSize[maxI] = tmpSize[j]; | 
| 242 |  |  | } | 
| 243 |  |  | // | 
| 244 |  |  | // Divide by pivot element and perform elimination | 
| 245 |  |  | // | 
| 246 |  |  | index[j] = maxI; | 
| 247 |  |  |  | 
| 248 |  |  | if ( fabs(A(j, j)) <= oopse::NumericConstant::epsilon ) { | 
| 249 |  |  | //vtkGenericWarningMacro(<<"Unable to factor linear system"); | 
| 250 |  |  | return false; | 
| 251 |  |  | } | 
| 252 |  |  |  | 
| 253 |  |  | if ( j != (size-1) ) { | 
| 254 |  |  | temp1 = 1.0 / A(j, j); | 
| 255 |  |  | for ( i = j + 1; i < size; i++ ) { | 
| 256 |  |  | A(i, j) *= temp1; | 
| 257 |  |  | } | 
| 258 |  |  | } | 
| 259 |  |  | } | 
| 260 |  |  |  | 
| 261 |  |  | return 1; | 
| 262 |  |  | } | 
| 263 |  |  |  | 
| 264 |  |  | /** | 
| 265 |  |  | * Solve linear equations Ax = b using LU decompostion A = LU where L is | 
| 266 |  |  | * lower triangular matrix and U is upper triangular matrix. | 
| 267 |  |  | * @param A input square matrix | 
| 268 |  |  | * @param index pivot indices | 
| 269 |  |  | * @param size size of the matrix and temporary arrays | 
| 270 |  |  | * @param tmpSize temporary array | 
| 271 |  |  | * @return true if inverse is computed, otherwise return false | 
| 272 |  |  | * @note A=LU and index[] are generated from method LUFactorLinearSystem). | 
| 273 |  |  | * Also, solution vector is written directly over input load vector. | 
| 274 |  |  | */ | 
| 275 |  |  | template<class MatrixType> | 
| 276 |  |  | void LUSolveLinearSystem(MatrixType& A, int *index, | 
| 277 |  |  | typename MatrixType::ElemPoinerType x, int size) | 
| 278 |  |  | { | 
| 279 |  |  | typedef typename MatrixType::ElemType Real; | 
| 280 |  |  | int i, j, ii, idx; | 
| 281 |  |  | Real sum; | 
| 282 |  |  | // | 
| 283 |  |  | // Proceed with forward and backsubstitution for L and U | 
| 284 |  |  | // matrices.  First, forward substitution. | 
| 285 |  |  | // | 
| 286 |  |  | for ( ii = -1, i = 0; i < size; i++ ) { | 
| 287 |  |  | idx = index[i]; | 
| 288 |  |  | sum = x[idx]; | 
| 289 |  |  | x[idx] = x[i]; | 
| 290 |  |  |  | 
| 291 |  |  | if ( ii >= 0 ) { | 
| 292 |  |  | for ( j = ii; j <= (i-1); j++ ) { | 
| 293 |  |  | sum -= A(i, j)*x[j]; | 
| 294 |  |  | } | 
| 295 |  |  | } else if (sum) { | 
| 296 |  |  | ii = i; | 
| 297 |  |  | } | 
| 298 |  |  |  | 
| 299 |  |  | x[i] = sum; | 
| 300 |  |  | } | 
| 301 |  |  | // | 
| 302 |  |  | // Now, back substitution | 
| 303 |  |  | // | 
| 304 |  |  | for ( i = size-1; i >= 0; i-- ) { | 
| 305 |  |  | sum = x[i]; | 
| 306 |  |  | for ( j = i + 1; j < size; j++ ) { | 
| 307 |  |  | sum -= A(i, j)*x[j]; | 
| 308 |  |  | } | 
| 309 |  |  | x[i] = sum / A(i, i); | 
| 310 |  |  | } | 
| 311 |  |  | } | 
| 312 |  |  |  | 
| 313 |  |  | } | 
| 314 |  |  |  | 
| 315 |  |  | #endif |