MATLAB: Parallel in fmincon: getappdata & indexing problem

fminconparallel computingparfor

I want to parallelize the finite differences calculations of fmincon. Doing that gives an error and I've isolated the two causes.
I've recreated the issue below, where the code inside the parfor is from my objective function for fmincon.
If I run fmincon without 'UseParallel',true then it works fine.
If I run fmincon with 'UseParallel',true, then I get the same errors as are generated using the parfor example below.
I understand why I get the error but I really need a workaround as using setappdata/getappdata between fmincon iterations helps with speed.
————–
Cause #1 – grabbing part of a vector set from getappdata
Cause #2 – the indexing of x00_i in the code below.
x00_i=zeros(2,2,1);
x00=ones(2,2);
setappdata(0,'x00',x00)
parpool
parfor ll=1:1:2
%%%%%%%%cause 1
  x1=  getappdata(0,'x00');
  x=x1(1,:);
%%%%%%%%

%%%%%%%%cause 2
    for ii= 1:1:2
        y=x(ii);
        x00_i(ii,:,:)=y;
    end
%%%%%%%%
end
FOLLOW-UP: If someone has a similar issue as this, I found a workaround for my case. I save x00 to multiple files indexed by the number of workers and then load/save it within each parallel loop by referring to the worker with: "t = getCurrentTask(); t.ID" . Labindex doesn't work as fmincon's parallel is akin to parfor, not spmd.
That way I can read and write and update it between iterations. In my case it doesn't matter if the worker number switches around.
In the end Walter's suggestions did not really help but it may help others.
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