Why does the standalone matlab (executable) code including the parallel computing feature do not work?

The (compiled) standalone matlab code (.exe) with the parallel computing/multi-core processing feature do not work even though the matlab script (.m) perfectly executes the task.

Is this the Matlab R2011b software limitation? Is there any solution to this problem?

Answer 1

[OCDER]

NEW ANSWER:

Turn your script into a function. This is the same issue seen here for Matlab 2011 version:

https://www.mathworks.com/matlabcentral/answers/19169-parfor-error-after-compiled

OLD ANSWER:

https://www.mathworks.com/support/bugreports/1251281

Seems like it's a known issue and thus you must use a workaround

gcp('nocreate')

Original Q&A here:

https://www.mathworks.com/matlabcentral/answers/228910-standalone-application-compiler-toolobox-of-a-code-using-the-parallel-computing-toolbox

[OCDER]

By any chance, are you compiling without java virtual machine? I get a similar message, "MATLAB: undefinedVarOrClass", if I try to compile something like this:

%main.m
gcp('nocreate')
parpool(4)

%compiler command
mcc -m main.m -R -nojvm

%running main.exe
Undefined variable "com" or class "com.mathworks.toolbox.distcomp.pmode.SessionInfo.NULL_SESSION_INFO".
Error in parpool (line 82)
Error in main (line 2)
MATLAB:undefinedVarOrClass

[OCDER]

Turn your script into a function. Someone had the exact issue and resolved it by doing that.

https://www.mathworks.com/matlabcentral/answers/19169-parfor-error-after-compiled

Answer 2

[Woo-Jae Cheong]

Yes. It is a known problem. However, Matlab R2011b version does not seem to recognize the function - gcp('nocreate'). Also, the second walkaround "%#function gcp" is just recognized as a comment in the script, and compiling with the pragma code at the top of the Matlab code does not make any difference. Here is the error message shown in the command prompt after running the executable code:

------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------
Starting matlabpool using the 'local' configuration ... connected to 4 labs.
The class "distcomp.remoteparfor" is undefined.
Perhaps Java is not running.

Error in parallel_function <line 430>

Error in 'myfilename' <line 76>

MATLAB: subscripting:undefinedClass
------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

In my opinion, it is the software version R2011b limitation. Do you agree?

Thank you in advance.

Answer 3

[Woo-Jae Cheong]

No. I am compiling with the Java® Virtual Machine (JVM™) that is enabled by default (unless specified).

[OCDER]

Hi Woo-Jae, these "ANSWER" section you're posting to should be reserved for actual answers and not comments. Use the "Comments" section to respond instead.

[Woo-Jae Cheong]

Thank you for letting me know. I will utilize the "Comments" section for my response to the suggestion.

[OCDER]

I edited the answer above. Did it work?

[Woo-Jae Cheong]

Yes. It worked very nicely. Thank you very much for your help.

[OCDER]

You're welcome!