Unrecognized variable in parfor loop

Hi, I'm experiencing some troubles with the parfor loop in a code with some innested for loops. It seems that a variable is not initialized in the correct way.

When trying to run this code:

parfor i=1:50
    beta=linbeta(i);
    HO=M_HO(alfa,beta);
    for j=1:50
        Id=linId(j);
        if (Iy<Id && Id<Iz) && Ix~=Iy && Iy~=Iz
            k=((Iy-Ix)*(Iz-Id)/((Id-Ix)*(Iz-Iy)))^0.5;
        elseif (Ix<Id && Id<Iy) && Ix~=Iy && Iy~=Iz
            k=((Id-Ix)*(Iz-Iy)/((Iy-Ix)*(Iz-Id)))^0.5;
        else
            k=0;
            printf('Not SAM or LAM');
        end
        K=RF(0,1-k^2,1);
        lintau=linspace(0,4*K,50);
        %Preallocation in memory of matrices for results storage
        M1=nan(length(linphi));  M2=M1;  M3=M1; az1M1=M1; az2M2=M1;  az3M3=M1;   Mx=M1;  My=M1;  Mz=M1;
        for m=1:length(linphi)
            phi=linphi(m);
            for l=1:length(lintau)
                [psi,theta]=tautoangles(Id,I,we,lintau(l)); %Angles PH, not BH
                alfaz1=sin(psi)*sin(theta); alfaz2=cos(psi)*sin(theta); alfaz3=cos(theta);
                PN=M_BH(phi,theta,psi)*HO*ON; %M_BH(phi,theta,psi)=PH
                quat=dcm2quat(PN);
                M=SRT(quat(1),quat(2),quat(3),quat(4),t,prop); %In inertial axes
                M_H=HO*ON*M; %In H frame
                Mx(m,l)=M_H(1);   My(m,l)=M_H(2);   Mz(m,l)=M_H(3);
                M_P=PN*M; %In principal axes
                M1(m,l)=M_P(1);   M2(m,l)=M_P(2);   M3(m,l)=M_P(3);
                az1M1(m,l)=alfaz1*M1(m,l);
                az2M2(m,l)=alfaz2*M2(m,l);
                az3M3(m,l)=alfaz3*M3(m,l);
            end
        end
        az1M1_av(i,j)=mean(mean(az1M1)); az2M2_av(i,j)=mean(mean(az2M2)); az3M3_av(i,j)=mean(mean(az3M3));
        Mx_av(i,j)=mean(mean(Mx)); My_av(i,j)=mean(mean(My)); Mz_av(i,j)=mean(mean(Mz));
    end
end

This error occurs at the parfor line:

The source code (...) for the parfor-loop that is trying to execute on the worker could not be found.

Caused by:

Unrecognized function or variable 'k'.

Error using remoteParallelFunction (line 84)

Worker unable to find file.

Unrecognized function or variable 'k'.

It seems to me that there is no reason why the variable "k" should not be initialized before being used in the loops. I tried also to preallocate it as empty variable as soon as the parfor loop starts, but the same error occurs. Instead, without parallel computing no error occurs (but running time is incredibly long).

Can someone give me any advice? Thanks a lot in advance!

[Edric Ellis]

There's nothing immediately obviously wrong with your code. Please could you try and narrow things down to a set of reproduction steps that we can execute. Also, which version of MATLAB are you using?

[Abhiroop Rastogi]

Hi Francesco,

As mentioned by Edric there is nothing wrong with assignment of "k". Can you please provide the code being executed before the "parfor" loop?

[Francesco Cuomo]

Hi,

thanks for your reply. I can't provide the full version of the code, but the problem was solved by evaluating the variables k and K before the parfor loop, in which K(j) is now used in the definition of the variable lintau.

Thank you.