How do I reset MATLAB to its launched state?

Is it possible to "reset" MATLAB? Sometimes I want to "restore" MATLAB to the way it is when it is launched (not the way it was when it is installed). Closing all the figures, resetting the path and clearing variables is relatively easy, but not as easy as:

close all; clear all; path(pathdef); clc;

You need extra flags since the "all" flag is not really all (e.g., a figure might be hidden or mfiles files might be locked).

Resetting non-persistent "default" values is harder. For example, if at some point the "DefaultFigurePosition" is modified:

set(0, 'DefaultFigurePosition', [100, 100, 100, 100])

that change needs to be identified and reversed.

The list of things to get a full reset seems long to me. There are also issues about do I want to restore MATLAB to the way it was when it started or the way it will be the next time it starts. At this point I would be happy with either (or a mix).

Answer 1

[Jan]

If you want it clean and simple:

!matlab &
exit

[Daniel Shub]

The more I/we play, the more I think this is the correct answer.

[Jan]

I'm very proud of finding out, that EXIT sets Matlab to a well defined status.

Answer 2

[Jan]

The hidden figures are closed by "close all hidden". Clearing the locked M-files can be controlled by unlocking all files loaded into memory. The default properties are set to the factory values at first and then adjusted to their local values in MATLABRC.

Script file TotalReset.m (not as function!)

% Clear command window:
clc;

% Close figures:
try
  close('all', 'hidden');
catch  % do nothing
end

% Closing figures might fail if the CloseRequestFcn of a figure
% blocks the execution. Fallback:
AllFig = allchild(0);
if ~isempty(AllFig)
   set(AllFig, 'CloseRequestFcn', '', 'DeleteFcn', '');
   delete(AllFig);
end

% EDITED: Initialize the default rand stream:
s = RandStream('mt19937ar', 'seed', 0);
RandStream.setDefaultStream(s);

% Clear loaded functions:
% (I avoid "clear all" here for educational reasons)
clear('functions');
clear('classes');
clear('java');
clear('global');
clear('import');  % Not from inside a function!
clear('variables');

% Stop and delete timers:
AllTimer = timerfindall;
if ~isempty(AllTimer)  % EDITED: added check
   stop(AllTimer);
   delete(AllTimer);
end

% Unlock M-files:
LoadedM = inmem;
for iLoadedM = 1:length(LoadedM)
   % EDITED: Use STRTOK to consider OO methods:
   aLoadedM = strtok(LoadedM{iLoadedM}, '.'); 
   munlock(aLoadedM);
   clear(aLoadedM);
end   

% Close open files:
fclose('all');

% Reset the warning status   EDITED:
warning('on', 'all');
lasterror('reset');
lastwarn('');

% Remove <Default>Properties from root:
prop = get(0, 'default');
propname = fieldnames(prop);
for iprop = 1:length(propname)
   set(0, propname{iprop}, 'remove');
end

% EDITED: Change to 1st user path to find "startup.m":
cd(strtok(userpath, pathsep));

% Restore original <Default>Properties of root,
% load default PATH, run STARTUP.m:
matlabrc;

% EDITED: No PACK even in scripts

Limitation: I don't know how to unlock Mex files externally and start a memory cleaning by PACK inside a script or function

EDITED: I've moved my second approach to a new answer.

[Daniel Shub]

This is very close, so I want to point out some bugs/typos if other people try this:

fclose('all); should be fclose('all');

stop(AllTimer);

delete(AllTimer);

should not be evaluated if AllTimer is empty

if ~isempty(AllTimer)

stop(AllTimer);

delete(AllTimer);

end

pack cannot be used in a script or from a shortcut.

[Daniel Shub]

Thank you for the answer. It is close to what I had. You deal with the default property names very nicely. I left closing files, fclose('all'), out of my script.

There are three obvious problems.

1. matlabrc does not reset the warning status, you need warning('on', 'all') to reset custom warning states.

2. If you are not at the prompt, but have entered "keyboard", this will fail. Something like:

try %#ok<TRYNC>

dbquit('all');

end

gets around that.

3. You do not change the directory. If I am working in a directory with a startup.m file, but MATLAB does not launch in this directory, startup.m is run, even though it would not be if I restarted MATLAB.

As you note, you do not reset the random number generators. I wonder if there are other things missing.

[Jan]

@Daniel: Thanks for crosschecking. Typos fixed.

Added: Reset LASTWARN and LASTERROR. RandStream is re-initialized now.

This is obvioulsy a cruel task. I cannot believe, that we've found all persistent data. The locked Mex files remain unresolved.

dbquit('all') stops the current function, and the TotalReset script also! "clear('import')" and "clear('variables')" is useful if TotalRest is called from the command line also. So I'd limit the use for a command line call and ignore problems originating from calling this script in debug mode.

[Daniel Shub]

You broke it again ...

By reseting the random stream you load something called RandStream.RandStream, into memory (inmem), but it unlocks with munlock('RandStream'). I also run into a problem if you try and unlock something that is not locked. Working with slightly different variable names leads to ...

LockedFilenameCellArray = inmem;

for iLockedFilename = 1:length(LockedFilenameCellArray)

LockFilenameString = LockedFilenameCellArray{iLockedFilename};

if mislocked(LockFilenameString)

munlock(LockFilenameString);

else

LockFilenameString = ...

LockFilenameString(1:(strfind(LockFilenameString, '.')-1));

if mislocked(LockFilenameString)

munlock(LockFilenameString);

end

end

end

[Daniel Shub]

I do not run into the same problem with the dbquit('all') command.

My usage is mainly based on a shortcut (in fact it is one of my only shortcuts) when I am debugging things. I am often deep into the debug environements/nested keyboards so the dbquit is important to me.

We are definitely not finding all the persistent data. I know analoginput creates persistent data like the timer, but these are easy to add.

Do you have an example of a locked mex file?

[Jan]

@Daniel: My FEX:Shuffle is locked, because some users urgently needed the RNG to be unaffected by "clear all". And graph2d\private\lineseriesmex.

Please try this: Create the script "disp('DBQUIT'); dbquit('all'); disp('READY')". Then set a breakpoint in any function, run until the breakpoint and call the script => "DBQUIT", but the 2nd DISP is not reached.

The timer is cleared already and I'll insert the safe unlocking of objects. MUNLOCK works on not locked files, but they must exist: "munlock plot" works, "munlock qqqqqq" fails.

[Daniel Shub]

Potential locked mex file solution:

[LoadedM, LoadedMex, LoadedJava] = inmem;

LoadedM = [LoadedM; LoadedMex];

It also finds the java items in memory which cannot be easily cleared.

[Jan]

@Daniel: You cannot unload a Mex-file with MUNLOCK. You need a method inside the Mex, which call mexUnLock().

[K E]

I would have never found the following in the documentation, but it's very useful so thanks Jan:

set(0, propname{iprop}, 'remove');

[Jan]

@K E: see http://www.mathworks.com/matlabcentral/answers/83075#answer_92788

[Jan]

The tic timer is not cleared yet. This does not show an error:

tic; TotalReset; toc

Answer 3

[Andreas Goser]

Please see if MATLABRC is what you need MATLABRC doc

If it is not completely would you need, you can create a startup.m file and add commands that you need. MATLABRC calls STARTUP.

[Daniel Shub]

Yes, using matlabrc is a good way of restoring default things that have been cleared. It does not provide a clearing mechanism and is therefore not a full reset. Jan's answer attempts to clear everything and then use matlabrc to restore. Seems like a reasonable way to go.

Answer 4

[Ganesh Tarone]

Error using connector.internal.doEnsureServiceOn

Error in Connector: Did not start the server. Desired port was: 31515. Last error was: Error while

starting socket: Net Exception: Address already in use: 127.0.0.1:31714, 10048

Error in connector.ensureServiceOn

Warning: Error in Connector: Did not start the server. Desired port was: 31515. Last error was: Error

while starting socket: Net Exception: Address already in use: 127.0.0.1:31714, 10048

> In sltemplate.ui.StartPage/showWithFallback

In sltemplate.ui.StartPage.show

Warning: Failed to start the web server. This could be because of the Java virtual machine. Restart

MATLAB without the flag -NoJVM to fix this.

> In slCustomizer/refresh

In slCustomizer.staticRefresh

In simulinkrc (line 41)

In start_simulink (line 19)

In slLibraryBrowser

In sltemplate.ui.StartPage/showWithFallback

In sltemplate.ui.StartPage.show

Warning: Failed to start the web server. This could be because of the Java virtual machine. Restart

MATLAB without the flag -NoJVM to fix this.

> In slprivate (line 11)

In dig.resetModel (line 7)

In slCustomizer/refresh

In slCustomizer.staticRefresh

In simulinkrc (line 41)

In start_simulink (line 19)

In slLibraryBrowser

In sltemplate.ui.StartPage/showWithFallback

In sltemplate.ui.StartPage.show

Warning: Issue starting Connector. Please check that port 31415 is available. Did not start the server.

Desired port was: 31515. Last error was: Error while starting socket: Net Exception: Address already in

use: 127.0.0.1:31714, 10048

Warning: An error occurred trying to load the Simulink HMI engine. Possible reasons include pressing

Ctrl+C or running MATLAB with the -nojvm option. Close and re-open any open any Simulink models to assure

proper functioning. For proper functioning of Simulink HMI and the Simulation Data Inspector, the JVM is

required.

> In Simulink.HMI.slhmi

In Simulink.HMI.slhmi

I am getting this error after writing simulink in command window ..please help