add toolbox

It is embarrassing to never use a external toolbox,

addpath(genpath('c:/data'));--ADDPATH DIRNAME prepends the specified directory to the current

savepath(genpath('c:/data'));-------SAVEPATH saves the current MATLABPATH in the pathdef.m, which was read on startup.

genpath('c:/data') return a path string, plus, recursively, all the subdirectories of D, including empty subdirectories.

open c:\data.m