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Matlab fails to access a list of variables

  1. Jun 30, 2013 #1
    So I have a list of variables, defined in my workspace, and I'm trying to access them each in turn to compare them to a larger matrix A. The eval function calls each variable in turn, stores it under temporary matrix B, then compares it to matrix A, does the necessary calculation, and stores it into matrix Z.

    Eval, always the capricious function, works if I try to do it manually but fails as I put this into m file and run it. The warning displayed is 'Undefined function or variable 'AAAN'.' even though that variable is there.

    This is my code:

    function Z = final(A,list)

    B = [];
    Z = [];
    K = log10(exp(1));

    for k = 1:length(list)
    eval(strcat('B = ',list{k},';'));
    for j = 2:length(B)
    for i = 2:length(A)
    if A(i,1) == B(j,1) && A(i,2) == B(j,2)
    Z = [Z; [A(i,1) A(i,2) K/(A(i,3)-B(1,3))]];


    Now I know most people will advise me to just use cell arrays but since dumping all those matrices into a fresh cell array will take me forever, I'm asking if there is a tweak or two to perform in order to get this to work.

  2. jcsd
  3. Jun 30, 2013 #2

    Say, I don't use matlab but would like to see some debugging, i.e., a confirmation that you are actually getting inside your function the data that you think you are getting.

    Again, because you say this is an interactive vs. batch thing...you should do all this 'debugging' in batch mode too (or *.m, style or whatever)

    can you explicitly show a small sample?

    Also, can you forget about the eval for a moment and just show what the data looks like INSIDE the function?
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