10-Jun-2023 06:33:30 correlation_test(): MATLAB/Octave version 5.2.0. Test correlation(). correlation_test01() Plot correlation functions. Graphics saved as "besselj_plot.png". Graphics saved as "besselk_plot.png". Graphics saved as "correlation_circular_plot.png" Graphics saved as "constant_plot.png". Graphics saved as "cubic_plot.png". Graphics saved as "damped_cosine_plot.png". Graphics saved as "damped_sine_plot.png". Graphics saved as "exponential_plot.png". Graphics saved as "gaussian_plot.png". Graphics saved as "hole_plot.png". Graphics saved as "linear_plot.png". Graphics saved as "matern_plot.png". Graphics saved as "pentaspherical_plot.png". Graphics saved as "power_plot.png". Graphics saved as "rational_quadratic_plot.png". Graphics saved as "spherical_plot.png". Graphics saved as "white_noise_plot.png". correlation_test02() sample_paths_cholesky() generates sample paths from the correlation matrix, factored using the Cholesky factor. It requires that the correlation matrix is nonnegative definite. SAMPLE_PATHS_EIGEN generates sample paths from the correlation matrix, factored using the eigen factorization. If the correlation matrix is not nonnegative definite, we simply suppress negative eigenvalues. SAMPLE_PATHS_FFT generates sample paths from the correlation matrix, factored using the FFT factorization of the correlation matrix after embedding in a circulant. Graphics saved as "besselj_paths.png". Graphics saved as "besselk_paths.png". Graphics saved as "circular_paths.png". Graphics saved as "constant_paths.png". Graphics saved as "cubic_paths.png". Graphics saved as "damped_cosine_paths.png". Graphics saved as "damped_sine_paths.png". Graphics saved as "exponential_paths.png". Graphics saved as "gaussian_paths.png". Graphics saved as "hole_paths.png". Graphics saved as "linear_paths.png". Graphics saved as "matern_paths.png". Graphics saved as "pentaspherical_paths.png". Graphics saved as "power_paths.png". Graphics saved as "rational_quadratic_paths.png". Graphics saved as "spherical_paths.png". Graphics saved as "white_noise_paths.png". correlation_test03(): Make plots of correlation functions. Graphics saved as "besselj_plots.png". Graphics saved as "besselk_plots.png". Graphics saved as "circular_plots.png". Graphics saved as "constant_plots.png". Graphics saved as "cubic_plots.png". Created "damped_cosine_plots.png". Graphics saved as "damped_sine_plots.png". Graphics saved as "exponential_plots.png". Graphics saved as "gaussian_plots.png". Graphics saved as "hole_plots.png". Graphics saved as "linear_plots.png". Graphics saved as "matern_plots.png". Graphics saved as "pentaspherical_plots.png". Graphics saved as "power_plots.png". Graphics saved as "rational_quadratic_plots.png". Graphics saved as "spherical_plots.png". Graphics saved as "white_noise_plots.png". correlation_test04(): Convert between a correlation and a covariance matrix. Covariance matrix K: Col: 1 2 3 4 5 Row 1 : 1 1 1 1 1 2 : 1 2 2 2 2 3 : 1 2 3 3 3 4 : 1 2 3 4 4 5 : 1 2 3 4 5 Correlation matrix C: Col: 1 2 3 4 5 Row 1 : 1 0.707107 0.57735 0.5 0.447214 2 : 0.707107 1 0.816497 0.707107 0.632456 3 : 0.57735 0.816497 1 0.866025 0.774597 4 : 0.5 0.707107 0.866025 1 0.894427 5 : 0.447214 0.632456 0.774597 0.894427 1 Variances: 1: 1 2: 1.41421 3: 1.73205 4: 2 5: 2.23607 Recovered covariance matrix K2: Col: 1 2 3 4 5 Row 1 : 1 1 1 1 1 2 : 1 2 2 2 2 3 : 1 2 3 3 3 4 : 1 2 3 4 4 5 : 1 2 3 4 5 correlation_test05(): correlation_brownian_display() displays the Brownian correlation Graphics saved as "correlation_brownian_plots.png". correlation_test06(): For non-stationary correlation functions: sample_paths2_cholesky() generates sample paths from the correlation matrix, factored using the Cholesky factor. It requires that the correlation matrix is nonnegative definite. sample_paths2_eigen() generates sample paths from the correlation matrix, factored using the eigen factorization. If the correlation matrix is not nonnegative definite, we simply suppress negative eigenvalues. sample_paths2_fft() generates sample paths from the correlation matrix, factored using the FFT factorization of the correlation matrix after embedding in a circulant. Graphics saved as "correlation_brownian_paths.png" correlation_test(): Normal end of execution. 10-Jun-2023 06:33:50