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31 package org.objectweb.proactive.examples.algebra;
32
33 import org.apache.log4j.Logger;
34
35 public class Matrix implements java.io.Serializable  {
36
37 static Logger logger = Logger.getLogger(Matrix.class.getName());
38
39 int m; int n; double[][] elements;
43 public Matrix() {
44 super();
45 }
46
47
48 public Matrix(int _m, int _n) {
49 super();
50 this.m = _m;
51 this.n = _n;
52 this.elements = new double[_m][_n];
53 }
54
55
56 public Matrix(int _n) {
57 this(_n, _n);
58 }
59
60
61 public Matrix(Matrix _m) {
62 this(_m.getHeight(), _m.getWidth());
63 logger.info("Matrix: constructor (Matrix _m)");
64 int i;
65 Row r;
66
67 for (i = 0; i < m; i++) {
68 r = _m.getRow(i);
69 this.setRow(i, r);
70 }
71 }
72
73
74 public Matrix(Column c_) {
75 this(c_.getSize(), 1);
76 this.setColumn(0, c_);
77 }
78
79
80 public Matrix(Row r_) {
81 this(1, r_.getSize());
82 this.setRow(0, r_);
83 }
84
85
86 public Matrix identity(int n) {
87 int i;
89 Matrix m;
90
91 m = new Matrix(n);
92
93 for (i = 0; i < n; i++) {
94 m.setElement(i, i, 1.0);
95 }
96 return m;
97 }
98
99
100 public Matrix identity() {
101 Matrix result;
102 if (this.m != this.n)
103 return null;
104 result = identity(this.m);
105 return result;
106 }
107
108
109 public double makeDiagOne(int i) {
110 double a;
111 int j;
112
113 a = this.getElement(i, i);
114 if (a == 0)
115 return a;
116
117 for (j = 0; j < this.n; j++) {
118 this.setElement(i, j, this.getElement(i, j) / a);
119 }
120 return a;
121 }
122
123
124 public Matrix transpose() {
125 Matrix mat;
126 int i,j;
127
128 mat = new Matrix(this.n, this.m);
130 for (i = 0; i < m; i++) {
131 for (j = 0; j < n; j++) {
132 mat.setElement(j, i, this.getElement(i, j));
133 }
134 }
135
136 return mat;
137 }
138
139
140 public void display() {
141 int i,j;
142
143 for (i = 0; i < this.m; i++) {
144 logger.info(i + " |");
145 for (j = 0; j < this.n; j++) {
146 logger.info(this.getElement(i, j) + " ");
147 }
148 logger.info("|");
149 }
150
151 System.out.println();
152
153 return;
154 }
155
156
157 public void randomizeFillIn() {
158 int i,j;
159
160 for (i = 0; i < this.m; i++) {
161 for (j = 0; j < this.n; j++) {
162 this.setElement(i, j, Math.random());
163 }
164 }
165 return;
166 }
167
168
169 public void setElement(int i, int j, double x) {
170 this.elements[i][j] = x;
171 return;
172 }
173
174
175 public double getElement(int i, int j) {
176 return this.elements[i][j];
177 }
178
179
180 public void setRow(int a, Vector r) {
181 int j;
182
183 for (j = 0; j < this.n; j++) {
184 this.setElement(a, j, r.getElement(j));
185 }
186 return;
187 }
188
189
190 public Row getRow(int i) {
191 Row r;
192 int j;
193
194 r = new Row(this.n);
195 for (j = 0; j < this.n; j++) {
196 r.setElement(j, this.getElement(i, j));
197 }
198
199 return r;
200 }
201
202
203 public void setColumn(int a, Vector c) {
204 int i;
205
206 for (i = 0; i < this.m; i++) {
207 this.setElement(i, a, c.getElement(i));
208 }
209 return;
210 }
211
212
213 public Column getColumn(int j) {
214 Column c;
215 int i;
216
217 c = new Column(this.m);
218 for (i = 0; i < this.m; i++) {
219 c.setElement(i, this.getElement(i, j));
220 }
221
222 return c;
223 }
224
225
226 public Matrix getBlock(int i0, int j0, int i1, int j1) {
227 Matrix result;
228 int i,j;
229
230 result = new Matrix((i1 - i0 + 1), (j1 - j0 + 1));
231
232 for (i = i0; i <= i1; i++) {
233 for (j = j0; j <= j1; j++) {
234 result.setElement((i - i0), (j - j0), this.getElement(i, j));
235 }
236 }
237
238 return result;
239 }
240
241
242 public void setBlock(int i0, int j0, Matrix m) {
243 int i,j;
244
245 for (i = 0; i < m.getHeight(); i++) {
246 for (j = 0; j < m.getWidth(); j++) {
247 this.setElement(i + i0, j + j0, m.getElement(i, j));
248 }
249 }
250 return;
251 }
252
253
254 public void swapRows(int a, int b) {
255 Row firstrow, lastrow;
256
257 firstrow = this.getRow(a);
258 lastrow = this.getRow(b);
259
260 this.setRow(a, lastrow);
261 this.setRow(b, firstrow);
262
263 return;
264 }
265
266
267 public void swapColumns(int a, int b) {
268 Column firstcol, lastcol;
269
270 firstcol = this.getColumn(a);
271 lastcol = this.getColumn(b);
272
273 this.setColumn(a, lastcol);
274 this.setColumn(b, firstcol);
275
276 return;
277 }
278
279
280 public Matrix rightProduct(Matrix m) {
281 int i,j,k;
283 Matrix result;
284 double s;
285
286 if (this.getWidth() != m.getHeight())
287 return null;
288
289 result = new Matrix(this.getHeight(), m.getWidth());
290
291 for (i = 0; i < result.getHeight(); i++) {
292 for (j = 0; j < result.getWidth(); j++) {
293 s = 0;
294 for (k = 0; k < m.getHeight(); k++) {
295 s = s + this.getElement(i, k) * m.getElement(k, j);
296 }
297 result.setElement(i, j, s);
298 }
299 }
300
301 return result;
302 }
303
304
305 public Vector rightProduct(Vector v) {
306 Vector result = new Vector(this.getHeight());
307 int i,j;
308 double s;
309
310 for (i = 0; i < this.getHeight(); i++) {
311 s = 0;
312 for (j = 0; j < this.getWidth(); j++) {
313 s = s + this.getElement(i, j) * v.getElement(j);
314 }
315 result.setElement(i, s);
316 }
317
318 return result;
319 }
320
321
322 public int getWidth() {
323 return this.n;
324 }
325
326
327 public int getHeight() {
328 return this.m;
329 }
330
331
332 public void rowLC(int firstrow, int secondrow, double alpha, double beta) {
333 int j;
334
335 for (j = 0; j < this.n; j++) {
336 this.setElement(firstrow, j, alpha * this.getElement(firstrow, j) + beta * this.getElement(secondrow, j));
337 }
338 return;
339 }
340
341
342 public void columnLC(int firstcol, int secondcol, double alpha, double beta) {
343 int i;
344
345 for (i = 0; i < this.m; i++) {
346 this.setElement(i, firstcol, alpha * this.getElement(i, firstcol) + beta * this.getElement(i, secondcol));
347 }
348 return;
349 }
350
351
352 public Matrix getInverse() {
353 Matrix source, result;
354 int i, p, r, s;
355 double alpha,beta, gamma;
356
357 source = new Matrix(this);
358
359 if (source.m != source.n)
360 return null; s = source.m;
362
363 result = identity(s);
364
365 for (r = 0; r < s; r++) {
366 p = source.findPivot(r);
368
369 source.swapRows(r, p); result.swapRows(r, p);
371
372 gamma = source.makeDiagOne(r);
374 result.rowLC(r, 0, 1 / gamma, 0);
376 for (i = 0; i < r; i++) {
379 alpha = 1;
380 beta = (-1) * source.getElement(i, r) / source.getElement(r, r);
381 source.rowLC(i, r, alpha, beta);
382 result.rowLC(i, r, alpha, beta);
383 }
384 for (i = r + 1; i < s; i++) {
385 alpha = 1;
386 beta = (-1) * source.getElement(i, r) / source.getElement(r, r);
387 source.rowLC(i, r, alpha, beta);
388 result.rowLC(i, r, alpha, beta);
389 }
390
391 }
392 logger.info("Inversion terminee pour n = " + this.m);
393
394 return result;
395 }
396
397
398 private int findPivot(int r) {
399 int i, result;
401
402 result = r;
403 for (i = r; i < this.m; i++) {
404 if (Math.abs(this.getElement(i, r)) > result)
405 result = i;
406 }
407 return result;
408 }
409
410
411 public double distance(Matrix mat) {
412 double result = 0;
413 double temp = 0;
414 int i,j;
415
416 if (this.m != mat.getHeight())
417 return -1;
418 if (this.n != mat.getWidth())
419 return -1;
420
421 for (i = 0; i < this.m; i++) {
422 for (j = 0; j < this.n; j++) {
423 temp = Math.abs(this.getElement(i, j) - mat.getElement(i, j));
424 if (temp > result)
425 result = temp;
426 }
427 }
428 return temp;
429 }
430
431
432 public double trace() {
433 double result = 0;
434 int i;
435
436 if (this.m != this.n)
437 return 0;
438 for (i = 0; i < m; i++) {
439 result = result + this.getElement(i, i);
440 }
441 return result;
442 }
443 }
444
445 |
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