How to use relative path to use matlab file in another computer

I have a folder in P:\study\Main. Inside the "Main" folder there is another sub folder called "Sub". There is a m file in main called "main_s.m". This refers another m file called "S2S.m" in "Sub" folder. To do this I had to use addpath('P:\Study\Main\Sub') in the m file. when I copy "Main" in to another computer different drive and execute "main_s.m" it will lead to an error. Is there a way to write a path which can be used in anywhere without altering the code in the m file?

[Stephen23]

You should read about absolute and relative filepaths:

http://www.mathworks.com/help/matlab/matlab_env/specify-file-names.html

Unless you really have total control over every computer where your code is run then you should take into consideration that hard-coding an absolute path is a poor idea, as it requires changing the code in order to change the location. It is better to make the path relative to the current directory, or force the user to select a root directory (e.g. by using a user interface, as an input argument, or by some setup file).

[Samuel]

In this case

addpath('Sub')

in your main_s.m should do the trick as long as sub stays in the main folder.

Answer 1

[Dennie]

You can use .\<folder_name>. The '.\' denotes that the current folder should contain the specified folder. So, having the code in the Main folder, the path should look like this:

addpath('.\Main\Sub')

[Harsha]

During the execution I received this message. Is it normal?

Warning: Name is nonexistent or not a directory: .\Main\Sub

> In path at 110

In addpath at 87

In main_s at 4

[Stephen23]

It is normal if that directory does not exist. If there is no directory in that location with that name then you will get that warning.

[Lucas Ritzdorf]

Worth noting that, if you're trying to build something like a Git repo (or other project folder that's intended to be portable), you can use this addpath() invocation from a startup.m file in that folder.

Answer 2

[Adam]

The safest way is probably to use

currentFile = mfilename( 'fullpath' );

which will give you the path of the currently executing m-file (i.e. your main_s.m), then you can just do e.g.

[pathstr,~,~] = fileparts( currentFile );
addpath( fullfile( pathstr, 'Sub' ) );

This will ensure that the path is always relative to that of the m file in which you put the code.