| 1 | /* | 
| 2 | * Copyright (C) 2000-2004  Object Oriented Parallel Simulation Engine (OOPSE) project | 
| 3 | * | 
| 4 | * Contact: oopse@oopse.org | 
| 5 | * | 
| 6 | * This program is free software; you can redistribute it and/or | 
| 7 | * modify it under the terms of the GNU Lesser General Public License | 
| 8 | * as published by the Free Software Foundation; either version 2.1 | 
| 9 | * of the License, or (at your option) any later version. | 
| 10 | * All we ask is that proper credit is given for our work, which includes | 
| 11 | * - but is not limited to - adding the above copyright notice to the beginning | 
| 12 | * of your source code files, and to any copyright notice that you may distribute | 
| 13 | * with programs based on this work. | 
| 14 | * | 
| 15 | * This program is distributed in the hope that it will be useful, | 
| 16 | * but WITHOUT ANY WARRANTY; without even the implied warranty of | 
| 17 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | 
| 18 | * GNU Lesser General Public License for more details. | 
| 19 | * | 
| 20 | * You should have received a copy of the GNU Lesser General Public License | 
| 21 | * along with this program; if not, write to the Free Software | 
| 22 | * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA. | 
| 23 | * | 
| 24 | */ | 
| 25 |  | 
| 26 | /** | 
| 27 | * @file SquareMatrix.hpp | 
| 28 | * @author Teng Lin | 
| 29 | * @date 10/11/2004 | 
| 30 | * @version 1.0 | 
| 31 | */ | 
| 32 | #ifndef MATH_SQUAREMATRIX_HPP | 
| 33 | #define MATH_SQUAREMATRIX_HPP | 
| 34 |  | 
| 35 | #include "math/RectMatrix.hpp" | 
| 36 |  | 
| 37 | namespace oopse { | 
| 38 |  | 
| 39 | /** | 
| 40 | * @class SquareMatrix SquareMatrix.hpp "math/SquareMatrix.hpp" | 
| 41 | * @brief A square matrix class | 
| 42 | * @template Real the element type | 
| 43 | * @template Dim the dimension of the square matrix | 
| 44 | */ | 
| 45 | template<typename Real, int Dim> | 
| 46 | class SquareMatrix : public RectMatrix<Real, Dim, Dim> { | 
| 47 | public: | 
| 48 |  | 
| 49 | /** default constructor */ | 
| 50 | SquareMatrix() { | 
| 51 | for (unsigned int i = 0; i < Dim; i++) | 
| 52 | for (unsigned int j = 0; j < Dim; j++) | 
| 53 | data_[i][j] = 0.0; | 
| 54 | } | 
| 55 |  | 
| 56 | /** copy constructor */ | 
| 57 | SquareMatrix(const RectMatrix<Real, Dim, Dim>& m)  : RectMatrix<Real, Dim, Dim>(m) { | 
| 58 | } | 
| 59 |  | 
| 60 | /** copy assignment operator */ | 
| 61 | SquareMatrix<Real, Dim>& operator =(const RectMatrix<Real, Dim, Dim>& m) { | 
| 62 | RectMatrix<Real, Dim, Dim>::operator=(m); | 
| 63 | return *this; | 
| 64 | } | 
| 65 |  | 
| 66 | /** Retunrs  an identity matrix*/ | 
| 67 |  | 
| 68 | static SquareMatrix<Real, Dim> identity() { | 
| 69 | SquareMatrix<Real, Dim> m; | 
| 70 |  | 
| 71 | for (unsigned int i = 0; i < Dim; i++) | 
| 72 | for (unsigned int j = 0; j < Dim; j++) | 
| 73 | if (i == j) | 
| 74 | m(i, j) = 1.0; | 
| 75 | else | 
| 76 | m(i, j) = 0.0; | 
| 77 |  | 
| 78 | return m; | 
| 79 | } | 
| 80 |  | 
| 81 | /** Retunrs  the inversion of this matrix. */ | 
| 82 | SquareMatrix<Real, Dim>  inverse() { | 
| 83 | SquareMatrix<Real, Dim> result; | 
| 84 |  | 
| 85 | return result; | 
| 86 | } | 
| 87 |  | 
| 88 | /** Returns the determinant of this matrix. */ | 
| 89 | double determinant() const { | 
| 90 | double det; | 
| 91 | return det; | 
| 92 | } | 
| 93 |  | 
| 94 | /** Returns the trace of this matrix. */ | 
| 95 | double trace() const { | 
| 96 | double tmp = 0; | 
| 97 |  | 
| 98 | for (unsigned int i = 0; i < Dim ; i++) | 
| 99 | tmp += data_[i][i]; | 
| 100 |  | 
| 101 | return tmp; | 
| 102 | } | 
| 103 |  | 
| 104 | /** Tests if this matrix is symmetrix. */ | 
| 105 | bool isSymmetric() const { | 
| 106 | for (unsigned int i = 0; i < Dim - 1; i++) | 
| 107 | for (unsigned int j = i; j < Dim; j++) | 
| 108 | if (fabs(data_[i][j] - data_[j][i]) > oopse::epsilon) | 
| 109 | return false; | 
| 110 |  | 
| 111 | return true; | 
| 112 | } | 
| 113 |  | 
| 114 | /** Tests if this matrix is orthogonal. */ | 
| 115 | bool isOrthogonal() { | 
| 116 | SquareMatrix<Real, Dim> tmp; | 
| 117 |  | 
| 118 | tmp = *this * transpose(); | 
| 119 |  | 
| 120 | return tmp.isDiagonal(); | 
| 121 | } | 
| 122 |  | 
| 123 | /** Tests if this matrix is diagonal. */ | 
| 124 | bool isDiagonal() const { | 
| 125 | for (unsigned int i = 0; i < Dim ; i++) | 
| 126 | for (unsigned int j = 0; j < Dim; j++) | 
| 127 | if (i !=j && fabs(data_[i][j]) > oopse::epsilon) | 
| 128 | return false; | 
| 129 |  | 
| 130 | return true; | 
| 131 | } | 
| 132 |  | 
| 133 | /** Tests if this matrix is the unit matrix. */ | 
| 134 | bool isUnitMatrix() const { | 
| 135 | if (!isDiagonal()) | 
| 136 | return false; | 
| 137 |  | 
| 138 | for (unsigned int i = 0; i < Dim ; i++) | 
| 139 | if (fabs(data_[i][i] - 1) > oopse::epsilon) | 
| 140 | return false; | 
| 141 |  | 
| 142 | return true; | 
| 143 | } | 
| 144 |  | 
| 145 | void diagonalize() { | 
| 146 | jacobi(m, eigenValues, ortMat); | 
| 147 | } | 
| 148 |  | 
| 149 | /** | 
| 150 | * Finds the eigenvalues and eigenvectors of a symmetric matrix | 
| 151 | * @param eigenvals a reference to a vector3 where the | 
| 152 | * eigenvalues will be stored. The eigenvalues are ordered so | 
| 153 | * that eigenvals[0] <= eigenvals[1] <= eigenvals[2]. | 
| 154 | * @return an orthogonal matrix whose ith column is an | 
| 155 | * eigenvector for the eigenvalue eigenvals[i] | 
| 156 | */ | 
| 157 | SquareMatrix<Real, Dim>  findEigenvectors(Vector<Real, Dim>& eigenValues) { | 
| 158 | SquareMatrix<Real, Dim> ortMat; | 
| 159 |  | 
| 160 | if ( !isSymmetric()){ | 
| 161 | throw(); | 
| 162 | } | 
| 163 |  | 
| 164 | SquareMatrix<Real, Dim> m(*this); | 
| 165 | jacobi(m, eigenValues, ortMat); | 
| 166 |  | 
| 167 | return ortMat; | 
| 168 | } | 
| 169 | /** | 
| 170 | * Jacobi iteration routines for computing eigenvalues/eigenvectors of | 
| 171 | * real symmetric matrix | 
| 172 | * | 
| 173 | * @return true if success, otherwise return false | 
| 174 | * @param a source matrix | 
| 175 | * @param w output eigenvalues | 
| 176 | * @param v output eigenvectors | 
| 177 | */ | 
| 178 | void jacobi(const SquareMatrix<Real, Dim>& a, | 
| 179 | Vector<Real, Dim>& w, | 
| 180 | SquareMatrix<Real, Dim>& v); | 
| 181 | };//end SquareMatrix | 
| 182 |  | 
| 183 |  | 
| 184 | #define ROT(a,i,j,k,l) g=a(i, j);h=a(k, l);a(i, j)=g-s*(h+g*tau);a(k, l)=h+s*(g-h*tau) | 
| 185 | #define MAX_ROTATIONS 60 | 
| 186 |  | 
| 187 | template<Real, int Dim> | 
| 188 | void SquareMatrix<Real, int Dim>::jacobi(SquareMatrix<Real, Dim>& a, | 
| 189 | Vector<Real, Dim>& w, | 
| 190 | SquareMatrix<Real, Dim>& v) { | 
| 191 | const int N = Dim; | 
| 192 | int i, j, k, iq, ip; | 
| 193 | double tresh, theta, tau, t, sm, s, h, g, c; | 
| 194 | double tmp; | 
| 195 | Vector<Real, Dim> b, z; | 
| 196 |  | 
| 197 | // initialize | 
| 198 | for (ip=0; ip<N; ip++) | 
| 199 | { | 
| 200 | for (iq=0; iq<N; iq++) v(ip, iq) = 0.0; | 
| 201 | v(ip, ip) = 1.0; | 
| 202 | } | 
| 203 | for (ip=0; ip<N; ip++) | 
| 204 | { | 
| 205 | b(ip) = w(ip) = a(ip, ip); | 
| 206 | z(ip) = 0.0; | 
| 207 | } | 
| 208 |  | 
| 209 | // begin rotation sequence | 
| 210 | for (i=0; i<MAX_ROTATIONS; i++) | 
| 211 | { | 
| 212 | sm = 0.0; | 
| 213 | for (ip=0; ip<2; ip++) | 
| 214 | { | 
| 215 | for (iq=ip+1; iq<N; iq++) sm += fabs(a(ip, iq)); | 
| 216 | } | 
| 217 | if (sm == 0.0) break; | 
| 218 |  | 
| 219 | if (i < 4) tresh = 0.2*sm/(9); | 
| 220 | else tresh = 0.0; | 
| 221 |  | 
| 222 | for (ip=0; ip<2; ip++) | 
| 223 | { | 
| 224 | for (iq=ip+1; iq<N; iq++) | 
| 225 | { | 
| 226 | g = 100.0*fabs(a(ip, iq)); | 
| 227 | if (i > 4 && (fabs(w(ip))+g) == fabs(w(ip)) | 
| 228 | && (fabs(w(iq))+g) == fabs(w(iq))) | 
| 229 | { | 
| 230 | a(ip, iq) = 0.0; | 
| 231 | } | 
| 232 | else if (fabs(a(ip, iq)) > tresh) | 
| 233 | { | 
| 234 | h = w(iq) - w(ip); | 
| 235 | if ( (fabs(h)+g) == fabs(h)) t = (a(ip, iq)) / h; | 
| 236 | else | 
| 237 | { | 
| 238 | theta = 0.5*h / (a(ip, iq)); | 
| 239 | t = 1.0 / (fabs(theta)+sqrt(1.0+theta*theta)); | 
| 240 | if (theta < 0.0) t = -t; | 
| 241 | } | 
| 242 | c = 1.0 / sqrt(1+t*t); | 
| 243 | s = t*c; | 
| 244 | tau = s/(1.0+c); | 
| 245 | h = t*a(ip, iq); | 
| 246 | z(ip) -= h; | 
| 247 | z(iq) += h; | 
| 248 | w(ip) -= h; | 
| 249 | w(iq) += h; | 
| 250 | a(ip, iq)=0.0; | 
| 251 | for (j=0;j<ip-1;j++) | 
| 252 | { | 
| 253 | ROT(a,j,ip,j,iq); | 
| 254 | } | 
| 255 | for (j=ip+1;j<iq-1;j++) | 
| 256 | { | 
| 257 | ROT(a,ip,j,j,iq); | 
| 258 | } | 
| 259 | for (j=iq+1; j<N; j++) | 
| 260 | { | 
| 261 | ROT(a,ip,j,iq,j); | 
| 262 | } | 
| 263 | for (j=0; j<N; j++) | 
| 264 | { | 
| 265 | ROT(v,j,ip,j,iq); | 
| 266 | } | 
| 267 | } | 
| 268 | } | 
| 269 | } | 
| 270 |  | 
| 271 | for (ip=0; ip<N; ip++) | 
| 272 | { | 
| 273 | b(ip) += z(ip); | 
| 274 | w(ip) = b(ip); | 
| 275 | z(ip) = 0.0; | 
| 276 | } | 
| 277 | } | 
| 278 |  | 
| 279 | if ( i >= MAX_ROTATIONS ) | 
| 280 | return false; | 
| 281 |  | 
| 282 | // sort eigenfunctions | 
| 283 | for (j=0; j<N; j++) | 
| 284 | { | 
| 285 | k = j; | 
| 286 | tmp = w(k); | 
| 287 | for (i=j; i<N; i++) | 
| 288 | { | 
| 289 | if (w(i) >= tmp) | 
| 290 | { | 
| 291 | k = i; | 
| 292 | tmp = w(k); | 
| 293 | } | 
| 294 | } | 
| 295 | if (k != j) | 
| 296 | { | 
| 297 | w(k) = w(j); | 
| 298 | w(j) = tmp; | 
| 299 | for (i=0; i<N; i++) | 
| 300 | { | 
| 301 | tmp = v(i, j); | 
| 302 | v(i, j) = v(i, k); | 
| 303 | v(i, k) = tmp; | 
| 304 | } | 
| 305 | } | 
| 306 | } | 
| 307 |  | 
| 308 | //    insure eigenvector consistency (i.e., Jacobi can compute | 
| 309 | //    vectors that are negative of one another (.707,.707,0) and | 
| 310 | //    (-.707,-.707,0). This can reek havoc in | 
| 311 | //    hyperstreamline/other stuff. We will select the most | 
| 312 | //    positive eigenvector. | 
| 313 | int numPos; | 
| 314 | for (j=0; j<N; j++) | 
| 315 | { | 
| 316 | for (numPos=0, i=0; i<N; i++) if ( v(i, j) >= 0.0 ) numPos++; | 
| 317 | if ( numPos < 2 ) for(i=0; i<N; i++) v(i, j) *= -1.0; | 
| 318 | } | 
| 319 |  | 
| 320 | return true; | 
| 321 | } | 
| 322 |  | 
| 323 | #undef ROT | 
| 324 | #undef MAX_ROTATIONS | 
| 325 |  | 
| 326 | } | 
| 327 |  | 
| 328 |  | 
| 329 | } | 
| 330 | #endif //MATH_SQUAREMATRIX_HPP |