MATLAB: Does MATLAB fail to start after I have called a MATLAB Engine application from within MATLAB 6.5.1 (R13SP1)

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From MATLAB, I spawn an external process using the bang (!) operator (or the UNIX, DOS, or SYSTEM command). That external process is a MATLAB Engine executable. This causes a second instance of MATLAB to start. After I have exited both MATLAB sessions, I am unable to restart MATLAB. It crashes on startup. The only way I am able to start MATLAB is to remove all of the files in my MATLAB preferences directory. Unfortunately, this also deletes all of my customizations to the MATLAB Desktop.

Best Answer

In order to work around this limitation, consider the following workaround:

Create a finish.m file which contains the following commands:

cd(prefdir);  %%move to the preferences directory
delete('*');    %%delete all of the files

This code deletes all of the files in the user's preferences directory. However, when MATLAB exits (after executing finish.m) it rewrites the files thus creating valid copies again for the next session.

Related Solutions

MATLAB: Is it possible to suppress the MATLAB Command Window from opening when you launch the MATLAB Engine using MATLAB 7.8 (R2009a)

The ability to suppress the MATLAB Command Window when starting a MATLAB Engine session is not available in MATLAB.

As a workaround, you can hide the command window once it has been opened using the ENGSETVISIBLE function. The following lines of code illustrate how you can do this:

Engine *ep;
ep = engOpen(NULL);
engSetVisible(ep, 0);

MATLAB: Is it possible to set the startup directory to be the directory I was in when I ended the previous session of MATLAB

The ability to preserve the directory between sessions is not available in MATLAB.

To work around this issue, you may use finish.m to have MATLAB use the last directory and use that upon starting a new session. The finish.m file would store the pathname of the last directory into your user path.

The finish.m file would include the lines:

p = pwd;
userpath(p);
savepath;

Note that the command FINISH automatically executes before leaving MATLAB if the file finish.m exists on the path. More information on this functionality can be found in the documentation by typing

doc finish

Alternatively, it is possible to use startup.m and finish.m files in order to have MATLAB remember the last directory and use that upon starting a new session. The finish.m file would store the pathname of the last directory into a variable, and the startup.m file would load this variable and use its contents to determine what to change the current directory to.

The startup.m file would include the lines

if (exist([matlabroot filesep 'work' filesep 'last_dir.mat']) == 2) 
      load ([matlabroot filesep 'work' filesep 'last_dir']) 
      cd(last_dir); 
end

whereas the finish.m file would include the lines

last_dir = pwd; 
save([matlabroot filesep 'work' filesep 'last_dir'],'last_dir');

Note that the command STARTUP automatically executes when starting MATLAB if the file startup.m exists, and the command FINISH automatically executes before leaving MATLAB if the file finish.m exists. More information on this functionality can be found in the documentation by typing

doc startup 
doc finish

Best Answer

Related Solutions

MATLAB: Is it possible to suppress the MATLAB Command Window from opening when you launch the MATLAB Engine using MATLAB 7.8 (R2009a)

MATLAB: Is it possible to set the startup directory to be the directory I was in when I ended the previous session of MATLAB

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