pathdef and resulting path very long

Hello,

I have a fresh installation of Matlab R2025b and I noticed a number of duplicate file warnings when opening Simulink in the style of:

Warning: Attempt to include duplicate file C:\Program Files\MATLAB\R2025b\Toolbox\simulink\ui\studio\config\m\+SLStudio\FileMenu.xml into Toolset . 
> In simulink.toolstrip.internal.loadConfig
In simulink.toolstrip.internal.refreshConfig
In slCustomizer/refresh
In slCustomizer.callRefresh
In slCustomizer>@()slCustomizer.callRefresh()
In slCustomizer.staticRefresh
In sl_refresh_customizations 

and

Warning: The toolset  already has a feature named ModelAdvisorSupportsLibrary. 
> In simulink.toolstrip.internal.loadConfig
In simulink.toolstrip.internal.refreshConfig
In slCustomizer/refresh
In slCustomizer.callRefresh
In slCustomizer>@()slCustomizer.callRefresh()
In slCustomizer.staticRefresh
In sl_refresh_customizatio

I tried to find the cause of this and saw that my path.m has over 2600 entries. Is this a normal size for a path.m and could it have anything to do with the warnings I encounter? (to be fair, it is a substantial installation with a number of toolboxes)

In my pathdef.m there are as many entries so

restoredefaultpath

does not change anything.

rehash toolboxcache

has no noticable effect either.

I noticed that the path includes many subfolders, not sure if that is normal behaviour, e.g:

C:\Program Files\MATLAB\R2025b\Toolbox\soc
C:\Program Files\MATLAB\R2025b\Toolbox\soc\blocks
C:\Program Files\MATLAB\R2025b\Toolbox\soc\customhardwaretarget
C:\Program Files\MATLAB\R2025b\Toolbox\soc\customhardwaretarget\registry
C:\Program Files\MATLAB\R2025b\Toolbox\soc\hardwareboards\alterasoc
C:\Program Files\MATLAB\R2025b\Toolbox\soc\hardwareboards\alterasoc\registry
....

Thanks for any help on the matter! :)

Answer 1

[Steven Lord]

If you have a lot of products and/or add-ons in your installation, the path may have a lot of entries.

V = ver;
S = split(path, pathsep);
fprintf("With %d products available, the path has %d entries.\n", ...
    numel(V), numel(S))

With 91 products available, the path has 2505 entries.

If you don't have a lot of products in your installation, did you call genpath on the toolbox subfolder of matlabroot or on a folder outside matlabroot with a lot of subfolders and/or a lot of nested subfolders?

If you want to restore the path to its factory-installed state, you could use restoredefaultpath -- though that's a big hammer. Read through its documentation carefully before using it.

[Tim]

First of all, thank you for your help.

I have a large number of products installed, so the amount of path entries is normal after all. From my investigation (I begrudgingly admit, my investigation was asking Gemini) I expected fewer entries. I will either just have to find another explanation for the fllood of warnings when opening Simulink or accept them as part of my life, as Simulink seems to run just fine despite them.