/**
* Test matrix square root.
*/
void test_m_sqrtm()
{
precision_t data[][5] = {
{ 5, -4, 1, 0, 0 },
{ -4, 6, -4, 1, 0 },
{ 1, -4, 6, -4, 1 },
{ 0, 1, -4, 6, -4 },
{ 0, 0, 1, -4, 6 }
};
matrix_t *A = m_initialize(5, 5);
fill_matrix_data(A, data);
matrix_t *X = m_sqrtm(A);
matrix_t *X_sq = m_product(X, X);
printf("A = \n");
m_fprint(stdout, A);
printf("X = sqrtm(A) = \n");
m_fprint(stdout, X);
printf("X * X = \n");
m_fprint(stdout, X_sq);
m_free(A);
m_free(X);
m_free(X_sq);
}
/**
* Compute the whitening matrix W_z for a matrix X.
*
* The whitening matrix, when applied to X, removes
* the first- and second-order statistics; that is,
* the mean and covariances are set to zero and the
* variances are equalized.
*
* @param X mean-subtracted input matrix
* @return whitening matrix W_z
*/
matrix_t * sphere(matrix_t *X)
{
// compute W_z = 2 * Cov(X)^(-1/2)
matrix_t *W_z_temp1 = m_covariance(X);
matrix_t *W_z_temp2 = m_sqrtm(W_z_temp1);
matrix_t *W_z = m_inverse(W_z_temp2);
m_elem_mult(W_z, 2);
// cleanup
m_free(W_z_temp1);
m_free(W_z_temp2);
return W_z;
}
int main (void) {
FILE *output = fopen ("testResults.txt", "w");
matrix_t *M = m_initialize (FILL, XDIM, YDIM);
matrix_t *R;
fprintf (output, "M = \n");
m_fprint (output, M);
// Test Group 3
fprintf (output, "\n-------------Test Group 3 -------------\n");
M = m_initialize (FILL, XDIM, YDIM);
fprintf (output, "m_norm (M, specRow) is SKIPPED IN THIS TEST\n");
R = m_sqrtm (M);
fprintf (output, "m_sqrtm(M) = \n");
m_fprint (output, R);
m_free (R);
precision val = m_determinant (M);
fprintf (output, "m_determinant(M) = %lf\n", val);
R = m_cofactor (M);
fprintf (output, "m_cofactor(M) = \n");
m_fprint (output, R);
m_free (R);
matrix_t *N = m_initialize (FILL, 3, 3);
R = m_cofactor (N);
fprintf (output, "Three-by-Three matrix N\n");
fprintf (output, "m_cofactor(N) = \n");
m_fprint (output, R);
m_free (R);
m_free (N);
N = m_initialize (FILL, 2, 2);
R = m_cofactor (N);
fprintf (output, "Two-by-Two matrix N\n");
fprintf (output, "m_cofactor(N) = \n");
m_fprint (output, R);
m_free (R);
m_free (N);
N = m_initialize (IDENTITY, XDIM, YDIM);
R = m_cofactor (N);
fprintf (output, "Identity matrix 6x6 N\n");
fprintf (output, "m_determinant(N)\n");
fprintf (output, "%lf\n", m_determinant (N));
fprintf (output, "m_cofactor(N) = \n");
m_fprint (output, R);
m_free (R);
m_free (N);
N = m_initialize (IDENTITY, 5, 5);
R = m_cofactor (N);
fprintf (output, "Identity matrix 5x5 N\n");
fprintf (output, "m_determinant(N)\n");
fprintf (output, "%lf\n", m_determinant (N));
fprintf (output, "m_cofactor(N) = \n");
m_fprint (output, R);
m_free (R);
m_free (N);
N = m_initialize (IDENTITY, 4, 4);
R = m_cofactor (N);
fprintf (output, "Identity matrix 4x4 N\n");
fprintf (output, "m_determinant (N)\n");
fprintf (output, "%lf\n", m_determinant (N));
fprintf (output, "m_cofactor (N) = \n");
m_fprint (output, R);
m_free (R);
m_free (N);
N = m_initialize (IDENTITY, 3, 3);
R = m_cofactor (N);
fprintf (output, "Identity matrix 3x3 N\n");
fprintf (output, "m_determinant (N)\n");
fprintf (output, "%lf\n", m_determinant (N));
fprintf (output, "m_cofactor (N) = \n");
m_fprint (output, R);
m_free (R);
m_free (N);
N = m_initialize (IDENTITY, 2, 2);
R = m_cofactor (N);
fprintf (output, "Identity matrix 2x2 N\n");
fprintf (output, "m_determinant (N)\n");
fprintf (output, "%lf\n", m_determinant (N));
fprintf (output, "m_cofactor (N) = \n");
m_fprint (output, R);
m_free (R);
m_free (N);
// Causes Segfault
//R = m_covariance (M);
//fprintf (output, "m_covariance(M) = \n");
//m_fprint (output, R);
// Causes ABORT - Double Free?
// m_free (R);
// m_free (M);
// m_free (R);
return 0;
}
