Construct a DataQueue, and call afterEach.

q = parallel.pool.DataQueue;
afterEach(q, @disp);

parfor i = 1:3
    send(q, i); 
end;

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     2

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Construct a PollableDataQueue.

p = parallel.pool.PollableDataQueue;

parfor i = 1
    send(p, i); 
end

poll(p)

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This example shows a function that creates a parfor wait bar. Create a DataQueue, and use afterEach to specify the function to execute each time the queue receives data. This example calls a subfunction that updates the wait bar.

Create a parfor-loop to carry out a computationally demanding task in MATLAB^®. Use send to send some dummy data on each iteration of the parfor-loop. When the queue receives the data, afterEach calls nUpdateWaitbar in the client MATLAB, and you can observe the wait bar progress.

function a = parforWaitbar

D = parallel.pool.DataQueue;
h = waitbar(0, 'Please wait ...');
afterEach(D, @nUpdateWaitbar);

N = 200;
p = 1;

parfor i = 1:N
    a(i) = max(abs(eig(rand(400))));
    send(D, i);
end

    function nUpdateWaitbar(~)
        waitbar(p/N, h);
        p = p + 1;
    end
end