Parfor with COMSOL object

Dear Concerned,

I have been reading through parallel processing toolbox lately to integrate COMSOL with matlab parallel processing and i am new to parallel processing with matlab aswell.

However i am struggling with the below problem.

In a parfor loop in am forced to load a COMSOL model object like the one below: "model = mphload('LIB_9AH_1D.mph');"

 parfor i = 1:2
        comsolPort=[2036 2037];
        t = getCurrentTask();
        labit=t.ID;
        mphstart(comsolPort(labit))
        import('com.comsol.model.*');
        import('com.comsol.model.util.*'); 
        model = mphload('LIB_9AH_1D.mph');
 end

Later i want to refer the 'model' object outside the parfor loop. I am doing this to invoke two COMSOL process in parallel to work with matlab.

However i get an error saying "Temporary variable model is used after the parfor loop,but its value is not available after the loop"

How to make a object value available after the parfor loop?. Any ways to approach this problem will be really helpful.

Matlab version and details:

MATLAB Version: 8.2.0.701 (R2013b) MATLAB License Number: 595731 Operating System: Microsoft Windows 7 Version 6.1 (Build 7601: Service Pack 1)

Answer 1

[Edric Ellis]

Outputs from a parfor loop need to be either sliced outputs, or reductions. In this case, a sliced output is probably most appropriate. You could put the model into a cell array:

parfor i = 1:2
   ...
   model{i} = ...;
end

[christober]

Dear Edric,

Thank you for the solution. I am able to access the model object this way inside the parfor loop

    parfor i = 1:2
       model{i} = mphload('LIB_9AH_1D.mph');   
       model{i}.variable('var8').set('D1_neg',D1_N{i}, 'Diffus'); 
    end

However i am not able to access the model object outside parfor.

       parfor i = 1:2
         model{i} = mphload('LIB_9AH_1D.mph');   
         model{i}.variable('var8').set('D1_neg',D1_N{i}, 'Diffus'); 
      end
      check_model = model{1};

In the above case 'check_model' is a empty matrix. The reason for doing this is the above code segment is inside a objective function and when each time the function is called the model gets loaded. However i wish to load the model once in the main file and pass it as a parameter to the objective function (to reduce the execution time).

I have accepted the above answer as it partly solved my problem.

Thank a lot.

Kind regards,

Chris