light_matrix.c 18 KB

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  1. #include "light_matrix.h"
  2. #include "helpler_funtions.h"
  3. #include <math.h>
  4. /************************************************************************/
  5. /* Private Function */
  6. /************************************************************************/
  7. static void swap(int *a, int *b) {
  8. int m;
  9. m = *a;
  10. *a = *b;
  11. *b = m;
  12. }
  13. static void perm(int list[], int k, int m, int *p, Mat *mat, MAT_TYPE *det) {
  14. int i;
  15. if (k > m) {
  16. MAT_TYPE res = mat->element[0][list[0]];
  17. for (i = 1; i < mat->row; i++) {
  18. res *= mat->element[i][list[i]];
  19. }
  20. if (*p % 2) {
  21. // odd is negative
  22. *det -= res;
  23. } else {
  24. // even is positive
  25. *det += res;
  26. }
  27. } else {
  28. // if the element is 0, we don't need to calculate the value for this
  29. // permutation
  30. // if(!equal(mat->element[k][list[k]], 0.0f))
  31. // perm(list, k + 1, m, p, mat, det);
  32. perm(list, k + 1, m, p, mat, det);
  33. for (i = k + 1; i <= m; i++) {
  34. // if(equal(mat->element[k][list[i]], 0.0f))
  35. // continue;
  36. swap(&list[k], &list[i]);
  37. *p += 1;
  38. perm(list, k + 1, m, p, mat, det);
  39. swap(&list[k], &list[i]);
  40. *p -= 1;
  41. }
  42. }
  43. }
  44. /************************************************************************/
  45. /* Public Function */
  46. /************************************************************************/
  47. /**
  48. * @brief creat a matrix instance by using dynamic memory
  49. *
  50. * @param row rows number of matrix
  51. * @param col cols number of matrix
  52. * @return Mat* pointer to the new matrix instance
  53. */
  54. Mat *MatNew(int row, int col) {
  55. /* make sure row and column num is positive */
  56. MAT_ASSERT(row > 0);
  57. MAT_ASSERT(col > 0);
  58. Mat *mat = NULL;
  59. mat = (Mat *)MAT_MALLOC(sizeof(Mat));
  60. if (mat) {
  61. mat->element = (MAT_TYPE **)MAT_MALLOC(row * sizeof(MAT_TYPE *));
  62. mat->buffer = (MAT_TYPE *)MAT_MALLOC(row * col * sizeof(MAT_TYPE));
  63. }
  64. if (mat->element == NULL || mat->buffer == NULL) {
  65. MatDelete(mat);
  66. return NULL;
  67. } else {
  68. for (int i = 0; i < row; i++) {
  69. mat->element[i] = &mat->buffer[i * col];
  70. }
  71. mat->row = row;
  72. mat->col = col;
  73. }
  74. return mat;
  75. }
  76. /**
  77. * @brief delete a matrix instance created by using dynamic memory
  78. *
  79. * @param mat pointer to the matrix instance
  80. */
  81. void MatDelete(Mat *mat) {
  82. if (mat == NULL) {
  83. return;
  84. }
  85. if (mat->element) {
  86. MAT_FREE(mat->element);
  87. }
  88. if (mat->buffer) {
  89. MAT_FREE(mat->buffer);
  90. }
  91. MAT_FREE(mat);
  92. }
  93. /**
  94. * @brief intialise a matrix, don't need dynamic memory allocation
  95. *
  96. * @param mat pointer to matrix instance
  97. * @param row matrix rows number
  98. * @param col matrix cols number
  99. * @param pdata matrix data buffer
  100. */
  101. void MatInit(Mat *mat, int row, int col, MAT_TYPE *pdata) {
  102. MAT_ASSERT(mat != NULL);
  103. MAT_ASSERT(pdata != NULL);
  104. MAT_ASSERT((row > 0 && col > 0));
  105. mat->row = row;
  106. mat->col = col;
  107. mat->buffer = pdata;
  108. for (int i = 0; i < row; i++) {
  109. mat->element[i] = &mat->buffer[i * col];
  110. }
  111. }
  112. /**
  113. * @brief swap rows of the matrix
  114. *
  115. * @param mat matrix pointer
  116. * @param i row number
  117. * @param j row number
  118. */
  119. void MatSwapRows(Mat *mat, size_t i, size_t j) {
  120. MAT_ASSERT(mat != NULL);
  121. MAT_ASSERT(i < mat->row);
  122. MAT_ASSERT(j < mat->row);
  123. if (i == j) {
  124. return;
  125. }
  126. if (mat->element) {
  127. for (size_t k = 0; k < mat->col; k++) {
  128. MAT_TYPE tmp = mat->element[i][k];
  129. mat->element[i][k] = mat->element[j][k];
  130. mat->element[j][k] = tmp;
  131. }
  132. }
  133. }
  134. /**
  135. * @brief swap cols of the matrix
  136. *
  137. * @param mat matrix pointer
  138. * @param i col number
  139. * @param j col number
  140. */
  141. void MatSwapCols(Mat *mat, size_t i, size_t j) {
  142. MAT_ASSERT(mat != NULL);
  143. MAT_ASSERT(i < mat->col);
  144. MAT_ASSERT(j < mat->col);
  145. if (i == j) {
  146. return;
  147. }
  148. if (mat->element) {
  149. for (size_t k = 0; k < mat->row; k++) {
  150. MAT_TYPE tmp = mat->element[k][i];
  151. mat->element[k][i] = mat->element[k][j];
  152. mat->element[k][j] = tmp;
  153. }
  154. }
  155. }
  156. /**
  157. * @brief set matrix element value
  158. *
  159. * @param mat matrix instance
  160. * @param val value buffer
  161. * @return error status
  162. */
  163. int MatSetVal(Mat *mat, MAT_TYPE *val) {
  164. int ret = MAT_EOK;
  165. MAT_ASSERT(mat != NULL);
  166. MAT_ASSERT(val != NULL);
  167. int row, col;
  168. if (mat->buffer == NULL || mat->element == NULL) {
  169. ret = -MAT_ERROR;
  170. }
  171. if (MAT_EOK == ret) {
  172. for (row = 0; row < mat->row; row++) {
  173. for (col = 0; col < mat->col; col++) {
  174. mat->element[row][col] = val[col + row * mat->col];
  175. }
  176. }
  177. }
  178. return ret;
  179. }
  180. /**
  181. * @brief dump the matrix data to a file to std out
  182. *
  183. * @param mat matrix pointer
  184. */
  185. void MatDump(const Mat *mat) {
  186. int row, col;
  187. if (mat == NULL) {
  188. return;
  189. }
  190. MAT_PRINTF("Mat %zux%zu:\n", mat->row, mat->col);
  191. for (row = 0; row < mat->row; row++) {
  192. for (col = 0; col < mat->col; col++) {
  193. MAT_PRINTF("%.4f\t", mat->element[row][col]);
  194. }
  195. MAT_PRINTF("\n");
  196. }
  197. }
  198. /**
  199. * @brief set all the element of the matrix to be zero
  200. *
  201. * @param mat matrix pointer
  202. * @return int MAT_ERROR code
  203. */
  204. int MatZeros(Mat *mat) {
  205. MAT_ASSERT(mat != NULL);
  206. int ret = MAT_EOK;
  207. int row, col;
  208. if (mat->buffer == NULL || mat->element == NULL) {
  209. ret = -MAT_ERROR;
  210. }
  211. if (MAT_EOK == ret) {
  212. for (row = 0; row < mat->row; row++) {
  213. for (col = 0; col < mat->col; col++) {
  214. mat->element[row][col] = 0;
  215. }
  216. }
  217. }
  218. return ret;
  219. }
  220. /**
  221. * @brief set the matrix to be a identity matrix
  222. *
  223. * @param mat
  224. * @return int
  225. */
  226. int MatEye(Mat *mat) {
  227. MAT_ASSERT(mat != NULL);
  228. int ret = MAT_EOK;
  229. ret = MatZeros(mat);
  230. if (MAT_EOK == ret) {
  231. for (int i = 0; i < min(mat->row, mat->col); i++) {
  232. mat->element[i][i] = 1.0f;
  233. }
  234. }
  235. return ret;
  236. }
  237. /**
  238. * @brief add two matrix by element
  239. *
  240. * @param src1 matrix to be added
  241. * @param src2 matrix to be added
  242. * @param dst dst = src1 + src2
  243. * @return int MAT_ERROR code
  244. */
  245. int MatAdd(Mat *src1, Mat *src2, Mat *dst) {
  246. MAT_ASSERT(src1 != NULL);
  247. MAT_ASSERT(src2 != NULL);
  248. MAT_ASSERT(dst != NULL);
  249. int ret = MAT_EOK;
  250. /* the two matrixs's column and row should be the same */
  251. if (!(src1->row == src2->row && src2->row == dst->row &&
  252. src1->col == src2->col && src2->col == dst->col)) {
  253. ret = -MAT_ERROR;
  254. }
  255. if (MAT_EOK == ret) {
  256. for (size_t row = 0; row < src1->row; row++) {
  257. for (size_t col = 0; col < src1->col; col++) {
  258. dst->element[row][col] =
  259. src1->element[row][col] + src2->element[row][col];
  260. }
  261. }
  262. }
  263. return ret;
  264. }
  265. /* dst = src1 - src2 */
  266. int MatSub(Mat *src1, Mat *src2, Mat *dst) {
  267. MAT_ASSERT(src1 != NULL);
  268. MAT_ASSERT(src2 != NULL);
  269. MAT_ASSERT(dst != NULL);
  270. int ret = MAT_EOK;
  271. if (!(src1->row == src2->row && src2->row == dst->row &&
  272. src1->col == src2->col && src2->col == dst->col)) {
  273. ret = -MAT_ERROR;
  274. }
  275. if (MAT_EOK == ret) {
  276. for (int row = 0; row < src1->row; row++) {
  277. for (int col = 0; col < src1->col; col++) {
  278. dst->element[row][col] =
  279. src1->element[row][col] - src2->element[row][col];
  280. }
  281. }
  282. }
  283. return ret;
  284. }
  285. /* dst = src1 * src2 */
  286. int MatMul(Mat *src1, Mat *src2, Mat *dst) {
  287. MAT_ASSERT(src1 != NULL);
  288. MAT_ASSERT(src2 != NULL);
  289. MAT_ASSERT(dst != NULL);
  290. int ret = MAT_EOK;
  291. if (src1->col != src2->row || src1->row != dst->row ||
  292. src2->col != dst->col) {
  293. ret = -MAT_ERROR;
  294. }
  295. if (MAT_EOK == ret) {
  296. for (int row = 0; row < dst->row; row++) {
  297. for (int col = 0; col < dst->col; col++) {
  298. MAT_TYPE temp = 0.0f;
  299. for (int i = 0; i < src1->col; i++) {
  300. temp += src1->element[row][i] * src2->element[i][col];
  301. }
  302. dst->element[row][col] = temp;
  303. }
  304. }
  305. }
  306. return ret;
  307. }
  308. /* dst = src' */
  309. int MatTrans(Mat *src, Mat *dst) {
  310. MAT_ASSERT(src != NULL);
  311. MAT_ASSERT(dst != NULL);
  312. int rslt = MAT_EOK;
  313. if (src->row != dst->col || src->col != dst->row) {
  314. rslt = -MAT_ERROR;
  315. }
  316. if (MAT_EOK == rslt) {
  317. for (int row = 0; row < dst->row; row++) {
  318. for (int col = 0; col < dst->col; col++) {
  319. dst->element[row][col] = src->element[col][row];
  320. }
  321. }
  322. }
  323. return rslt;
  324. }
  325. /**
  326. * @brief calculate determinant of the matrix
  327. *
  328. * @param mat matrix instance
  329. * @return the determinant
  330. */
  331. MAT_TYPE MatDet(Mat *mat) {
  332. MAT_ASSERT(mat != NULL);
  333. int rslt = MAT_EOK;
  334. MAT_TYPE det = 0.0f;
  335. int plarity = 0;
  336. int *list;
  337. int i;
  338. /* the mat should be a square matrix */
  339. if (mat->row != mat->col) {
  340. rslt = -MAT_ERROR;
  341. }
  342. if (MAT_EOK == rslt) {
  343. list = (int *)MAT_MALLOC(sizeof(int) * mat->col);
  344. if (list == NULL) {
  345. rslt = -MAT_ENOMEM;
  346. } else {
  347. for (i = 0; i < mat->col; i++)
  348. list[i] = i;
  349. perm(list, 0, mat->row - 1, &plarity, mat, &det);
  350. MAT_FREE(list);
  351. }
  352. }
  353. return det;
  354. }
  355. /* dst = adj(src) */
  356. int MatAdj(Mat *src, Mat *dst) {
  357. int rslt = MAT_EOK;
  358. MAT_TYPE det = 0;
  359. if (src->row != src->col || src->row != dst->row || src->col != dst->col) {
  360. rslt = -MAT_ERROR;
  361. }
  362. if (MAT_EOK == rslt) {
  363. Mat *smat = NULL;
  364. smat = MatNew(src->row - 1, src->col - 1);
  365. if (smat) {
  366. for (int row = 0; row < src->row; row++) {
  367. for (int col = 0; col < src->col; col++) {
  368. int r = 0;
  369. for (int i = 0; i < src->row; i++) {
  370. if (i == row)
  371. continue;
  372. int c = 0;
  373. for (int j = 0; j < src->col; j++) {
  374. if (j == col)
  375. continue;
  376. smat->element[r][c] = src->element[i][j];
  377. c++;
  378. }
  379. r++;
  380. }
  381. det = MatDet(smat);
  382. if ((row + col) % 2)
  383. det = -det;
  384. dst->element[col][row] = det;
  385. }
  386. }
  387. MatDelete(smat);
  388. } else {
  389. rslt = -MAT_ENOMEM;
  390. }
  391. }
  392. return rslt;
  393. }
  394. int MatCopy(Mat *src, Mat *dst) {
  395. int ret = MAT_EOK;
  396. if (src->row != dst->row || src->col != dst->col) {
  397. ret = -MAT_ERROR;
  398. }
  399. if (MAT_EOK == ret) {
  400. for (int row = 0; row < src->row; row++) {
  401. for (int col = 0; col < src->col; col++)
  402. dst->element[row][col] = src->element[row][col];
  403. }
  404. }
  405. return ret;
  406. }
  407. int MatEig(Mat *mat, MAT_TYPE *eig_val, Mat *eig_vec, MAT_TYPE eps, int njt) {
  408. MAT_ASSERT(mat != NULL);
  409. MAT_ASSERT(eig_val != NULL);
  410. MAT_ASSERT(eig_vec != NULL);
  411. int rslt = MAT_EOK;
  412. int i, j;
  413. int nDim = mat->row;
  414. /* mat should be a squre matrix */
  415. if (mat->row != mat->col) {
  416. rslt = -MAT_ERROR;
  417. }
  418. Mat *temp_mat = NULL;
  419. if (MAT_EOK == rslt) {
  420. temp_mat = MatNew(mat->row, mat->col);
  421. if (temp_mat != NULL) {
  422. MatCopy(mat, temp_mat);
  423. for (i = 0; i < nDim; i++) {
  424. eig_vec->element[i][i] = 1.0f;
  425. for (int j = 0; j < nDim; j++) {
  426. if (i != j)
  427. eig_vec->element[i][j] = 0.0f;
  428. }
  429. }
  430. int nCount = 0; // iteration count
  431. while (1) {
  432. // find maxial element in non-diagram of mat
  433. MAT_TYPE dbMax = temp_mat->element[0][1];
  434. int nRow = 0;
  435. int nCol = 1;
  436. for (i = 0; i < nDim; i++) { // row
  437. for (j = 0; j < nDim; j++) { // col
  438. MAT_TYPE d = fabs(temp_mat->element[i][j]);
  439. if ((i != j) && (d > dbMax)) {
  440. dbMax = d;
  441. nRow = i;
  442. nCol = j;
  443. }
  444. }
  445. }
  446. if (dbMax < eps) {
  447. break;
  448. }
  449. if (nCount > njt) {
  450. break;
  451. }
  452. nCount++;
  453. MAT_TYPE dbApp = temp_mat->element[nRow][nRow];
  454. MAT_TYPE dbApq = temp_mat->element[nRow][nCol];
  455. MAT_TYPE dbAqq = temp_mat->element[nCol][nCol];
  456. // calculate rotation angle
  457. MAT_TYPE dbAngle = 0.5 * atan2(-2 * dbApq, dbAqq - dbApp);
  458. MAT_TYPE dbSinTheta = sin(dbAngle);
  459. MAT_TYPE dbCosTheta = cos(dbAngle);
  460. MAT_TYPE dbSin2Theta = sin(2 * dbAngle);
  461. MAT_TYPE dbCos2Theta = cos(2 * dbAngle);
  462. temp_mat->element[nRow][nRow] = dbApp * dbCosTheta * dbCosTheta +
  463. dbAqq * dbSinTheta * dbSinTheta +
  464. 2 * dbApq * dbCosTheta * dbSinTheta;
  465. temp_mat->element[nCol][nCol] = dbApp * dbSinTheta * dbSinTheta +
  466. dbAqq * dbCosTheta * dbCosTheta -
  467. 2 * dbApq * dbCosTheta * dbSinTheta;
  468. temp_mat->element[nRow][nCol] =
  469. 0.5f * (dbAqq - dbApp) * dbSin2Theta + dbApq * dbCos2Theta;
  470. temp_mat->element[nCol][nRow] = temp_mat->element[nRow][nCol];
  471. for (i = 0; i < nDim; i++) {
  472. if ((i != nCol) && (i != nRow)) {
  473. dbMax = temp_mat->element[i][nRow];
  474. temp_mat->element[i][nRow] =
  475. temp_mat->element[i][nCol] * dbSinTheta + dbMax * dbCosTheta;
  476. temp_mat->element[i][nCol] =
  477. temp_mat->element[i][nCol] * dbCosTheta - dbMax * dbSinTheta;
  478. }
  479. }
  480. for (j = 0; j < nDim; j++) {
  481. if ((j != nCol) && (j != nRow)) {
  482. dbMax = temp_mat->element[nRow][j];
  483. temp_mat->element[nRow][j] =
  484. temp_mat->element[nCol][j] * dbSinTheta + dbMax * dbCosTheta;
  485. temp_mat->element[nCol][j] =
  486. temp_mat->element[nCol][j] * dbCosTheta - dbMax * dbSinTheta;
  487. }
  488. }
  489. // calculate eigen vector
  490. for (i = 0; i < nDim; i++) {
  491. dbMax = eig_vec->element[i][nRow];
  492. eig_vec->element[i][nRow] =
  493. eig_vec->element[i][nCol] * dbSinTheta + dbMax * dbCosTheta;
  494. eig_vec->element[i][nCol] =
  495. eig_vec->element[i][nCol] * dbCosTheta - dbMax * dbSinTheta;
  496. }
  497. }
  498. // calculate eigen value
  499. for (i = 0; i < nDim; i++) {
  500. eig_val[i] = temp_mat->element[i][i];
  501. }
  502. // set sign
  503. for (i = 0; i < nDim; i++) {
  504. MAT_TYPE dSumVec = 0;
  505. for (j = 0; j < nDim; j++)
  506. dSumVec += eig_vec->element[j][i];
  507. if (dSumVec < 0) {
  508. for (j = 0; j < nDim; j++)
  509. eig_vec->element[j][i] *= -1;
  510. }
  511. }
  512. MatDelete(temp_mat);
  513. } else {
  514. rslt = -MAT_ENOMEM;
  515. }
  516. }
  517. return rslt;
  518. }
  519. MAT_TYPE MatNorm(Mat *mat) {
  520. MAT_TYPE max_eig_val = 0.0f;
  521. int rslt = MAT_EOK;
  522. /* mat should be a squre matrix */
  523. if (mat->row != mat->col) {
  524. rslt = -MAT_ERROR;
  525. }
  526. if (MAT_EOK == rslt) {
  527. MAT_TYPE *eig_val = NULL;
  528. Mat *eig_vec = NULL;
  529. eig_val = (MAT_TYPE *)MAT_MALLOC(mat->row * sizeof(MAT_TYPE));
  530. eig_vec = MatNew(mat->row, mat->col);
  531. if (eig_val != NULL && eig_vec != NULL) {
  532. MatEig(mat, eig_val, eig_vec, 1e-6, 100);
  533. for (int i = 0; i < mat->row; i++) {
  534. if (eig_val[i] > max_eig_val)
  535. max_eig_val = eig_val[i];
  536. }
  537. } else {
  538. rslt = -MAT_ENOMEM;
  539. }
  540. MAT_FREE(eig_val);
  541. MatDelete(eig_vec);
  542. }
  543. return max_eig_val;
  544. }
  545. int MatInvByLu(Mat *const A, Mat *inv) {
  546. MAT_ASSERT(A != NULL);
  547. MAT_ASSERT(inv != NULL);
  548. size_t N = A->col;
  549. Mat *L = NULL, *U = NULL, *P = NULL;
  550. int ret = MAT_EOK;
  551. if (A->col != inv->col || A->row != inv->row) {
  552. ret = -MAT_ERROR;
  553. }
  554. if (ret == MAT_EOK) {
  555. L = MatNew(N, N);
  556. U = MatNew(N, N);
  557. P = MatNew(N, N);
  558. if (L == NULL || U == NULL || P == NULL) {
  559. ret = -MAT_ENOMEM;
  560. }
  561. }
  562. if (ret == MAT_EOK) {
  563. MatEye(L);
  564. MatEye(P);
  565. MatCopy(A, U);
  566. for (size_t n = 0; n < N; n++) {
  567. if (fabs(U->element[n][n]) < (MAT_TYPE)FLT_EPSILON) {
  568. for (size_t i = n + 1; i < N; i++) {
  569. if (fabs(U->element[i][n]) > (MAT_TYPE)FLT_EPSILON) {
  570. MatSwapRows(U, i, n);
  571. MatSwapRows(P, i, n);
  572. MatSwapRows(L, i, n);
  573. MatSwapCols(L, i, n);
  574. }
  575. }
  576. }
  577. if ((float)(fabs(U->element[n][n])) < FLT_EPSILON) {
  578. ret = -MAT_ERROR;
  579. break;
  580. }
  581. for (size_t i = n + 1; i < N; i++) {
  582. L->element[i][n] = U->element[i][n] / U->element[n][n];
  583. for (size_t k = 0; k < N; k++) {
  584. U->element[i][k] -= L->element[i][n] * U->element[n][k];
  585. }
  586. }
  587. }
  588. if (ret == MAT_EOK) {
  589. for (size_t col = 0; col < N; col++) {
  590. for (size_t i = 0; i < N; i++) {
  591. for (size_t j = 0; j < i; j++) {
  592. P->element[i][col] -= L->element[i][j] * P->element[j][col];
  593. }
  594. }
  595. }
  596. for (size_t col = 0; col < N; col++) {
  597. for (size_t k = 0; k < N; k++) {
  598. size_t i = N - k - 1;
  599. for (size_t j = i + 1; j < N; j++) {
  600. P->element[i][col] -= U->element[i][j] * P->element[j][col];
  601. }
  602. P->element[i][col] /= U->element[i][i];
  603. }
  604. }
  605. for (size_t i = 0; i < N; i++) {
  606. for (size_t j = 0; j < N; j++) {
  607. if (!isfinite(P->element[i][j])) {
  608. ret = -MAT_ERROR;
  609. }
  610. }
  611. }
  612. }
  613. }
  614. if (ret == MAT_EOK) {
  615. MatCopy(P, inv);
  616. }
  617. MatDelete(L);
  618. MatDelete(U);
  619. MatDelete(P);
  620. return ret;
  621. }
  622. // dst = src^(-1)
  623. int MatInv(Mat *src, Mat *dst) {
  624. int ret = MAT_EOK;
  625. MAT_TYPE det;
  626. int row, col;
  627. /* the mat should be a square matrix */
  628. if (src->row != src->col || src->row != dst->row || src->col != dst->col) {
  629. ret = -MAT_EINVAL;
  630. }
  631. if (ret == MAT_EOK) {
  632. Mat *adj_mat = MatNew(src->row, src->col);
  633. if (adj_mat) {
  634. if (MatAdj(src, adj_mat) == MAT_EOK) {
  635. det = MatDet(src);
  636. if (!is_zerof(det)) {
  637. for (row = 0; row < src->row; row++) {
  638. for (col = 0; col < src->col; col++)
  639. dst->element[row][col] = adj_mat->element[row][col] / det;
  640. }
  641. ret = MAT_EOK;
  642. } else {
  643. ret = -MAT_EINVAL;
  644. }
  645. } else {
  646. ret = -MAT_ERROR;
  647. }
  648. MatDelete(adj_mat);
  649. } else {
  650. ret = -MAT_ENOMEM;
  651. }
  652. }
  653. return ret;
  654. }