diff options
Diffstat (limited to 'src/common/matrix.c')
-rw-r--r-- | src/common/matrix.c | 63 |
1 files changed, 0 insertions, 63 deletions
diff --git a/src/common/matrix.c b/src/common/matrix.c deleted file mode 100644 index 60f9afb..0000000 --- a/src/common/matrix.c +++ /dev/null | |||
@@ -1,63 +0,0 @@ | |||
1 | #include "common/matrix.h" | ||
2 | #include <assert.h> | ||
3 | #include <memory.h> | ||
4 | #include <stdlib.h> | ||
5 | #include "common/mem.h" | ||
6 | |||
7 | static inline IntSquareMatrix *matrix_without_row(IntSquareMatrix *target, IntSquareMatrix *origin, | ||
8 | IntVector omitted_row) { | ||
9 | int origin_row, target_row; | ||
10 | |||
11 | for (origin_row = 0, target_row = 0; origin_row < origin->dim; ++origin_row) | ||
12 | if (origin_row != omitted_row) | ||
13 | target->elements[target_row++] = origin->elements[origin_row]; | ||
14 | |||
15 | return target; | ||
16 | } | ||
17 | |||
18 | static inline IntVector det_dev_sign(IntVector row, IntVector col) { | ||
19 | assert(row > 0 && col > 0); | ||
20 | return ((row + col) % 2 == 0) ? 1 : -1; | ||
21 | } | ||
22 | |||
23 | static inline IntVector det_reduce(IntSquareMatrix *matrix) { | ||
24 | IntSquareMatrix sub_matrix; | ||
25 | int row; | ||
26 | IntVector det = 0; | ||
27 | |||
28 | assert(matrix->dim > 2); | ||
29 | |||
30 | sub_matrix.dim = matrix->dim - 1; | ||
31 | sub_matrix.elements = malloc_or_die(sub_matrix.dim * sizeof(IntVector *)); | ||
32 | |||
33 | for (row = 0; row < matrix->dim; ++row) | ||
34 | det += matrix->elements[row][matrix->dim - 1] | ||
35 | * det_dev_sign(row + 1, matrix->dim) | ||
36 | * matrix_int_det(matrix_without_row(&sub_matrix, matrix, row)); | ||
37 | |||
38 | |||
39 | free(sub_matrix.elements); | ||
40 | return det; | ||
41 | } | ||
42 | |||
43 | IntVector matrix_int_det(IntSquareMatrix *matrix) { | ||
44 | assert(matrix->dim > 0); | ||
45 | switch (matrix->dim) { | ||
46 | case 1: | ||
47 | return matrix->elements[0][0]; | ||
48 | |||
49 | case 2: | ||
50 | return matrix->elements[0][0] * matrix->elements[1][1] - matrix->elements[0][1] * matrix->elements[1][0]; | ||
51 | |||
52 | default: | ||
53 | return det_reduce(matrix); | ||
54 | } | ||
55 | } | ||
56 | |||
57 | void matrix_reshape(IntVector **bi_dim, IntVector *flat, int width, int height) { | ||
58 | int row; | ||
59 | assert(width > 0 && height > 0); | ||
60 | |||
61 | for (row = 0; row < height; ++row) | ||
62 | bi_dim[row] = flat + row * width; | ||
63 | } | ||