MATLAB: Help! “Parfor” error: Subscripted assignment dimension mismatch

parallel computingparforsubscripted assignment dimension mismatch

Hi. I'm converting some sequential codes into parallel codes. The former works well. But I came across the following errors when running the parallel codes. Can anyone help me? Thanks.
??? Error using ==> parallel_function>make_general_channel/channel_general at 843 Subscripted assignment dimension mismatch.
Error in ==> parallel_function>distributed_execution at 752 [tags, out] = P.getCompleteIntervals(chunkSize);
Error in ==> parallel_function at 564 R = distributed_execution(…
Error in ==> SensitivityForNaturalBreachFreqParfor3 at 8 SANaturalBreachFreq = zeros(4,14);
??? Operation terminated by user during ==> NormalFlow
In ==> NaturalBreachFreq at 275 [h_begin, u_begin] = NormalFlow(Q_begin,B_prtC,s_prtC,n_prtC);
In ==> parallel_function>make_general_channel/channel_general at 843 O = F(C{:});
In ==> remoteParallelFunction at 28 out = distcompMakeByteBufferHandle(distcompserialize(feval(channel, channelArgs{:})));
****************The parallel codes:
 SANaturalBreachFreq = zeros(4,14);  % The outputs
 parfor i=1:4      % Test four iterations
     V = zeros(1,14); 
     V(i,1:3) = SA3Parameters(i,1:3);   % All inputs loaded into the workspace
     [Z_prtC,Z_levee] = ChnlElevations(H_prtC,V(i,1),rDep_chnl,rDep_bsn); 
      E_weak = 0.2*V(i,2)^(-0.5)*1e-6; 
      Lweak = 0.05*L_prtC/V(i,3);          
      [BreachYearNo,BigBreachYearNo,BreachNo,BigBreachNo,AvulsionNo,AllBreachNo,MajorBreachW,MajorBreachQout_pct,...
          Avulsion,AllBreachYearNo]...
              = NaturalBreachFreq(Qd,Qsd,Qpct_overtop,Qpct_bifur,Qpct_avlsn,yBifur,Big_pct,H_prtC,Z_prtC,Z_levee,...
                 B_prtC,s_prtC,n_prtC,tauCr,V(i,2),nDcr,V(i,3),Lweak,E,E_weak,D_breach0,B_breach0,dL,n_star,...
                 n_breach,dL_outfl,p_wash,d50,ws_m,rho_s,rho_m,p,dt);
      V(i,4) =  AvulsionNo;          
      if ~isempty(Avulsion)            
          V(i,5) = Avulsion(1); 
          V(i,6) = Z_levee(Avulsion(3))/Hbar;              
      end
          V(i,7) = AllBreachYearNo;
          V(i,8) =  BreachYearNo;
          V(i,9) =  BigBreachYearNo;
          V(i,10) = AllBreachNo;
          V(i,11) =  BreachNo;
          V(i,12) = BigBreachNo;  
          V(i,13) = MajorBreachW; 
          V(i,14) = MajorBreachQout_pct; 
          SANaturalBreachFreq(i,:) = V;     
 end

Best Answer

In the body of your loop, you create V as 1-by-14, but you assign into it using "V(i,1)" etc. Finally, you assign into "SANaturalBreachFreq(i,:) = V;" - this will be incorrect because "V" is now not the correct size. Surely you should be doing something more like
    parfor i = 1:4
      V = zeros(1,4);
      V(1) = ...;
      ...
      V(14) = ...;
      SANaturalBreachFreq(i,:) = V;
    end
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