How to use variables of one file to other

In main.m program mean, standard deviation and energy is calculated as,

Mean = mean(ch1);

standard_Deviation = std(ch1);

energy = sum(abs(ch1).^2);

classifier;

these variables are declared as global but when I try to run classifier.m it shows error at line

test=[Mean standard_Dviation energy];

[Konstantinos Sofos]

A good point to start is here: Share Data Between Workspaces

The most secure way to extend the scope of a function variable is to use function input and output arguments, which allow you to pass values of variables and not to use global variables

Regards

[dpb]

I can find no TMW function classifier at www.mathworks.com so no way to know but one would presume this is also a function so besides the link above start with

help classifier  % for specific expectations of the function

and then read the "Getting Started" section in the online doc's to understand the use of Matlab in general.