Hi everybody, I encounter with this error message. : ""Attempt to reference field of non-structure array. "" I would be grateful if you could help.

the erorr is in first line:

last               = Run.steps(1);          % index of last sampled dags
log_score          = Run.Log_Scores(last);  % the current log score
V_vec              = Run.v_vec{last};       % the current couple-uncouple vectors 
lambda_coup_vec    = Run.lambda_coup_vec{last};
lambda_uncoup_vec  = Run.lambda_uncoup_vec{last};
% Output on screen: 
fprintf('\n###########################################################\n')
fprintf('The new DBN cpBGe MCMC simulation has been started \n')
fprintf('###########################################################\n')
fprintf('Log-likelihood-value of the initial graph: %1.5f \n',log_score)
fprintf('###########################################################\n\n')
%%%Start of the MCMC simulation
Counter = 1;
for i = last:steps
  [log_score,lambda_uncoup_vec, lambda_coup_vec, nue_var,V_vec] = MCMC_INNER( ...
              step_iterations, DAG, log_score, MATRIX, DATA_ALL, mue_0, ...
              Cov_mat, nue_var, lambda_uncoup_vec, lambda_coup_vec, ...
              k_transition,V_vec);
  if (i>=floor(steps/2))
    Run.Log_Scores(Counter)          = log_score;
    Run.steps(1)                     = i+1;
    Run.lambda_coup_vec{Counter}     = lambda_coup_vec;
    Run.lambda_uncoup_vec{Counter}   = lambda_uncoup_vec;
    Run.v_vec{Counter}               = V_vec;
    Counter = Counter+1;
  end
end

[dpb]

run is a Matlab builtin command that you apparently have redefined into an array which isn't a structure but an "ordinary" array...type

which run

and let us see how it is defined...it would be defined it appears or would have gotten a different message

[Steven Lord]

run is a built-in function. Run (with a capital R) is not, though it could easily lead to confusion.

[dpb]

Ah, my bad on the capitalization, Steven....still, he's got an array it appears that is trying to use as a structure and which 'll show that for certain...(again, presuming he capitalizes it consistently :) )

Answer 1

[Steven Lord]

Before you execute that line of code, look at the Run variable. You're trying to index into it as though it was a struct array, but from the error message it is NOT a struct array. My guess is that whatever code you ran to generate the variable named Run did not work as expected, perhaps returning Run as an empty array "placeholder", the array [].