MATLAB: How to replace matlapool by parpool in the code

Hello everyone !

I worked with a code in matlab 2012 , and it worked very well at first.. But then, i used matlab 2015 and my function matlabpool disapeared , replaced by parpool. The problem is that i didn't succeed in replacing my piece of code using matlabpool.

 arete_connex3D = NaN(neighborhood_size*neighborhood_size*neighborhood_size-1,numel(ROI_struct));
    indexNonNaN = find(~isnan(ROI_struct));
    if ~isempty(indexNonNaN)
        isOpen = matlabpool('size') > 0;
        if ~isOpen
            matlabpool('open','local',3);
        end
        for n = 1:numel(indexNonNaN)
            index_in_matrix = indexNonNaN(n);
            pos = ind2sub_new(sz,index_in_matrix,'mat');
            x = pos(1); y = pos(2); z = pos(3);
            ind2 = 1;
            for i = (x-floor(neighborhood_size/2)):(x+floor(neighborhood_size/2))
                for j = (y-floor(neighborhood_size/2)):(y+floor(neighborhood_size/2))
                    for k = (z-floor(neighborhood_size/2)):(z+floor(neighborhood_size/2))
                        if i>=1 && i<=sz(1) && j>=1 &&j<=sz(2) && k>=1 && k<=sz(3) ...
                                && ~isequal([x,y,z],[i,j,k])
                            arete_connex3D(ind2,index_in_matrix) = sub2ind_3D(sz,[i,j,k]);
                            ind2 = ind2 + 1;
                        end
                    end
                end
            end
        end
        isOpen = matlabpool('size') > 0;
        if isOpen
            matlabpool close 
        end
    end

I tried some things but it didn't work, i really don't know how to do that. Thank you in advance for your help.

Best Answer

Something like this perhaps,

function varargout = matlabpool(varargin)
     varargout={};
     arg1=varargin{1};
     switch arg1
       case 'open'
         parpool(varargin{2:end});
       case 'close'
         delete(gcp('nocreate'));
       case  'size'
         p = gcp('nocreate'); % If no pool, do not create new one.
        if isempty(p)
            poolsize = 0;
        else
            poolsize = p.NumWorkers;
        end
        varargout={poolsize};
    otherwise %number of workers
         if ~isnumeric(arg1)
           arg1=num2str(arg1);
         end
         parpool(arg1);
end

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