| 175 |  | * @param w output eigenvalues | 
| 176 |  | * @param v output eigenvectors | 
| 177 |  | */ | 
| 178 | < | void jacobi(const SquareMatrix<Real, Dim>& a, | 
| 179 | < | Vector<Real, Dim>& w, | 
| 178 | > | bool jacobi(const SquareMatrix<Real, Dim>& a, Vector<Real, Dim>& w, | 
| 179 |  | SquareMatrix<Real, Dim>& v); | 
| 180 |  | };//end SquareMatrix | 
| 181 |  |  | 
| 183 |  | #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) | 
| 184 |  | #define MAX_ROTATIONS 60 | 
| 185 |  |  | 
| 186 | < | template<Real, int Dim> | 
| 187 | < | void SquareMatrix<Real, int Dim>::jacobi(SquareMatrix<Real, Dim>& a, | 
| 188 | < | Vector<Real, Dim>& w, | 
| 190 | < | SquareMatrix<Real, Dim>& v) { | 
| 186 | > | template<typename Real, int Dim> | 
| 187 | > | bool SquareMatrix<Real, Dim>::jacobi(const SquareMatrix<Real, Dim>& a, Vector<Real, Dim>& w, | 
| 188 | > | SquareMatrix<Real, Dim>& v) { | 
| 189 |  | const int N = Dim; | 
| 190 |  | int i, j, k, iq, ip; | 
| 191 |  | double tresh, theta, tau, t, sm, s, h, g, c; | 
| 193 |  | Vector<Real, Dim> b, z; | 
| 194 |  |  | 
| 195 |  | // initialize | 
| 196 | < | for (ip=0; ip<N; ip++) | 
| 197 | < | { | 
| 198 | < | for (iq=0; iq<N; iq++) v(ip, iq) = 0.0; | 
| 199 | < | v(ip, ip) = 1.0; | 
| 196 | > | for (ip=0; ip<N; ip++) { | 
| 197 | > | for (iq=0; iq<N; iq++) | 
| 198 | > | v(ip, iq) = 0.0; | 
| 199 | > | v(ip, ip) = 1.0; | 
| 200 |  | } | 
| 201 | < | for (ip=0; ip<N; ip++) | 
| 202 | < | { | 
| 203 | < | b(ip) = w(ip) = a(ip, ip); | 
| 204 | < | z(ip) = 0.0; | 
| 201 | > |  | 
| 202 | > | for (ip=0; ip<N; ip++) { | 
| 203 | > | b(ip) = w(ip) = a(ip, ip); | 
| 204 | > | z(ip) = 0.0; | 
| 205 |  | } | 
| 206 |  |  | 
| 207 |  | // begin rotation sequence | 
| 208 | < | for (i=0; i<MAX_ROTATIONS; i++) | 
| 209 | < | { | 
| 210 | < | sm = 0.0; | 
| 211 | < | for (ip=0; ip<2; ip++) | 
| 212 | < | { | 
| 213 | < | for (iq=ip+1; iq<N; iq++) sm += fabs(a(ip, iq)); | 
| 214 | < | } | 
| 215 | < | if (sm == 0.0) break; | 
| 208 | > | for (i=0; i<MAX_ROTATIONS; i++) { | 
| 209 | > | sm = 0.0; | 
| 210 | > | for (ip=0; ip<2; ip++) { | 
| 211 | > | for (iq=ip+1; iq<N; iq++) | 
| 212 | > | sm += fabs(a(ip, iq)); | 
| 213 | > | } | 
| 214 | > |  | 
| 215 | > | if (sm == 0.0) | 
| 216 | > | break; | 
| 217 |  |  | 
| 218 | < | if (i < 4) tresh = 0.2*sm/(9); | 
| 219 | < | else tresh = 0.0; | 
| 218 | > | if (i < 4) | 
| 219 | > | tresh = 0.2*sm/(9); | 
| 220 | > | else | 
| 221 | > | tresh = 0.0; | 
| 222 |  |  | 
| 223 | < | for (ip=0; ip<2; ip++) | 
| 224 | < | { | 
| 225 | < | for (iq=ip+1; iq<N; iq++) | 
| 226 | < | { | 
| 227 | < | g = 100.0*fabs(a(ip, iq)); | 
| 228 | < | if (i > 4 && (fabs(w(ip))+g) == fabs(w(ip)) | 
| 229 | < | && (fabs(w(iq))+g) == fabs(w(iq))) | 
| 230 | < | { | 
| 231 | < | a(ip, iq) = 0.0; | 
| 232 | < | } | 
| 233 | < | else if (fabs(a(ip, iq)) > tresh) | 
| 234 | < | { | 
| 235 | < | 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 | < | } | 
| 223 | > | for (ip=0; ip<2; ip++) { | 
| 224 | > | for (iq=ip+1; iq<N; iq++) { | 
| 225 | > | g = 100.0*fabs(a(ip, iq)); | 
| 226 | > | if (i > 4 && (fabs(w(ip))+g) == fabs(w(ip)) | 
| 227 | > | && (fabs(w(iq))+g) == fabs(w(iq))) { | 
| 228 | > | a(ip, iq) = 0.0; | 
| 229 | > | } else if (fabs(a(ip, iq)) > tresh) { | 
| 230 | > | h = w(iq) - w(ip); | 
| 231 | > | if ( (fabs(h)+g) == fabs(h)) { | 
| 232 | > | t = (a(ip, iq)) / h; | 
| 233 | > | } else { | 
| 234 | > | theta = 0.5*h / (a(ip, iq)); | 
| 235 | > | t = 1.0 / (fabs(theta)+sqrt(1.0+theta*theta)); | 
| 236 |  |  | 
| 237 | < | for (ip=0; ip<N; ip++) | 
| 238 | < | { | 
| 239 | < | b(ip) += z(ip); | 
| 274 | < | w(ip) = b(ip); | 
| 275 | < | z(ip) = 0.0; | 
| 276 | < | } | 
| 277 | < | } | 
| 237 | > | if (theta < 0.0) | 
| 238 | > | t = -t; | 
| 239 | > | } | 
| 240 |  |  | 
| 241 | + | c = 1.0 / sqrt(1+t*t); | 
| 242 | + | s = t*c; | 
| 243 | + | tau = s/(1.0+c); | 
| 244 | + | h = t*a(ip, iq); | 
| 245 | + | z(ip) -= h; | 
| 246 | + | z(iq) += h; | 
| 247 | + | w(ip) -= h; | 
| 248 | + | w(iq) += h; | 
| 249 | + | a(ip, iq)=0.0; | 
| 250 | + |  | 
| 251 | + | for (j=0;j<ip-1;j++) | 
| 252 | + | ROT(a,j,ip,j,iq); | 
| 253 | + |  | 
| 254 | + | for (j=ip+1;j<iq-1;j++) | 
| 255 | + | ROT(a,ip,j,j,iq); | 
| 256 | + |  | 
| 257 | + | for (j=iq+1; j<N; j++) | 
| 258 | + | ROT(a,ip,j,iq,j); | 
| 259 | + | for (j=0; j<N; j++) | 
| 260 | + | ROT(v,j,ip,j,iq); | 
| 261 | + | } | 
| 262 | + | } | 
| 263 | + | }//for (ip=0; ip<2; ip++) | 
| 264 | + |  | 
| 265 | + | for (ip=0; ip<N; ip++) { | 
| 266 | + | b(ip) += z(ip); | 
| 267 | + | w(ip) = b(ip); | 
| 268 | + | z(ip) = 0.0; | 
| 269 | + | } | 
| 270 | + |  | 
| 271 | + | } // end for (i=0; i<MAX_ROTATIONS; i++) | 
| 272 | + |  | 
| 273 |  | if ( i >= MAX_ROTATIONS ) | 
| 274 | < | return false; | 
| 274 | > | return false; | 
| 275 |  |  | 
| 276 |  | // sort eigenfunctions | 
| 277 | < | for (j=0; j<N; j++) | 
| 278 | < | { | 
| 279 | < | k = j; | 
| 280 | < | tmp = w(k); | 
| 281 | < | for (i=j; i<N; i++) | 
| 282 | < | { | 
| 283 | < | if (w(i) >= tmp) | 
| 284 | < | { | 
| 285 | < | k = i; | 
| 286 | < | tmp = w(k); | 
| 287 | < | } | 
| 288 | < | } | 
| 289 | < | if (k != j) | 
| 290 | < | { | 
| 291 | < | w(k) = w(j); | 
| 292 | < | w(j) = tmp; | 
| 293 | < | for (i=0; i<N; i++) | 
| 294 | < | { | 
| 295 | < | tmp = v(i, j); | 
| 302 | < | v(i, j) = v(i, k); | 
| 303 | < | v(i, k) = tmp; | 
| 304 | < | } | 
| 305 | < | } | 
| 277 | > | for (j=0; j<N; j++) { | 
| 278 | > | k = j; | 
| 279 | > | tmp = w(k); | 
| 280 | > | for (i=j; i<N; i++) { | 
| 281 | > | if (w(i) >= tmp) { | 
| 282 | > | k = i; | 
| 283 | > | tmp = w(k); | 
| 284 | > | } | 
| 285 | > | } | 
| 286 | > |  | 
| 287 | > | if (k != j) { | 
| 288 | > | w(k) = w(j); | 
| 289 | > | w(j) = tmp; | 
| 290 | > | for (i=0; i<N; i++)  { | 
| 291 | > | tmp = v(i, j); | 
| 292 | > | v(i, j) = v(i, k); | 
| 293 | > | v(i, k) = tmp; | 
| 294 | > | } | 
| 295 | > | } | 
| 296 |  | } | 
| 297 |  |  | 
| 298 |  | //    insure eigenvector consistency (i.e., Jacobi can compute | 
| 301 |  | //    hyperstreamline/other stuff. We will select the most | 
| 302 |  | //    positive eigenvector. | 
| 303 |  | int numPos; | 
| 304 | < | for (j=0; j<N; j++) | 
| 305 | < | { | 
| 306 | < | 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; | 
| 304 | > | for (j=0; j<N; j++) { | 
| 305 | > | for (numPos=0, i=0; i<N; i++) if ( v(i, j) >= 0.0 ) numPos++; | 
| 306 | > | if ( numPos < 2 ) for(i=0; i<N; i++) v(i, j) *= -1.0; | 
| 307 |  | } | 
| 308 |  |  | 
| 309 |  | return true; | 
| 314 |  |  | 
| 315 |  | } | 
| 316 |  |  | 
| 328 | – |  | 
| 329 | – | } | 
| 317 |  | #endif //MATH_SQUAREMATRIX_HPP |