// Call helper functions
void matrixTranspose(float A[][3], float A_trans[][3]);
void matrixVectorMultiplication(float A[][3], float B[][1], float C[][1]);
void matrixMultiplication(float A[][3], float B[][3], float C[][3]);
void rotationMatrix(float theta, float R[3][3], char axis);

// Define matrices as global variables
// 3x3 matrices
float mat_A[3][3] = {{1, 2, 3}, {4, 5, 6}, {7, 8, 9}};
float mat_B[3][3] = {{9, 8, 7}, {6, 5, 4}, {3, 2, 1}};
float mat_A_trans[3][3] = {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}};  // Initialize
float mat_C[3][3] = {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}};    // Initialize
float mat_D[3][3] = {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}};    // Initialize

float Rx[3][3] = {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}};   // Initialize
float Ry[3][3] = {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}};   // Initialize
float Rz[3][3] = {{0, 0, 0}, {0, 0, 0}, {0, 0, 0}};   // Initialize

// 3x1 vectors
float vec_a[3][1] = {{1}, {2}, {3}};
float vec_b[3][1] = {{0}, {0}, {0}};    // Initialize

// Rotation angles in radians
float theta_x = 0.1;
float theta_y = 0.2;
float theta_z = 0.3;

// Get A transpose
matrixTranspose(mat_A, mat_A_trans);

// Get b = A*a
matrixVectorMultiplication(mat_A, vec_a, vec_b);

// Get C = A*B
matrixMultiplication(mat_A, mat_B, mat_C);

// Get D = B*A
matrixMultiplication(mat_B, mat_A, mat_D);

// Get rotation matrices
rotationMatrix(theta_x, Rx, 'x');   // Rotation about x-axis
rotationMatrix(theta_y, Ry, 'y');   // Rotation about y-axis
rotationMatrix(theta_z, Rz, 'z');   // Rotation about z-axis