int main(int argc, char *argv[])
{
int n = 3; //rows
int m = 3; //cols
double **matrix;
FILE *fp;
//Det could be computed only from square matrix
if (n != m && n > 1)
error(2);
fp = fopen("matrix.txt", "r");
if (!fp)
error(0);
matrix = alloc_matrix(n, m);
parse_file(fp, matrix, n, m);
print_matrix(matrix, n, m);
printf("Det: %f\n", compute_det(matrix, n));
dealloc_matrix(matrix, n);
fclose(fp);
getchar();
return 0;
}
double compute_det(double **matrix, int n)
{
int i;
int j;
int whole_matrix;
int submatrix;
double det = 0;
double **minor;
if (n == 2) {
//sarrus
det = matrix[0][0] * matrix[1][1] - matrix[0][1] * matrix[1][0];
} else {
det = 0;
for (whole_matrix = 0; whole_matrix < n; whole_matrix++) {
minor = (double **)malloc((n - 1) * sizeof(double *));
for (i = 0; i < n - 1; i++)
minor[i] = (double *)malloc((n - 1) * sizeof(double));
for (i = 0; i < n - 1; i++) {
submatrix = 0;
for (j = 0; j < n; j++) {
if (j == whole_matrix)
continue;
minor[i][submatrix] = matrix[i + 1][j];
submatrix++;
}
}
det += pow(-1.0, 1.0 + whole_matrix + 1.0) * matrix[0][whole_matrix] * compute_det(minor, n - 1);
for (i = 0; i < n - 1; i++)
free(minor[i]);
free(minor);
}
}
return det;
}
inline bool GjkCollisionState::closest(VectorF& v)
{
compute_det();
for (int s = bits; s; --s) {
if ((s & bits) == s) {
if (valid(s | last_bit)) {
bits = s | last_bit;
if (bits != 15)
compute_vector(bits, v);
return true;
}
}
}
if (valid(last_bit)) {
bits = last_bit;
v = y[last];
return true;
}
return false;
}
