07-Jan-2022 19:57:59 fd3d_poisson_test(): MATLAB/Octave version 9.8.0.1380330 (R2020a) Update 2 fd3d_poisson() is a simple Poisson equation solver for a 3d rectangular block region. Using a 5 by 5 by 5 grid The RMS error was 0.00367301 fd3d_poisson_test(): Normal end of execution. 07-Jan-2022 19:57:59