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What is the cause of undefined variable or function error.

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tarmizi adam 2012-10-12

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Hello and a good day. I just wanna ask a question about 'undefined variable or function' error.

i got an error saying

"Undefined variable or function Target might refer to the function target."

I'm just curious. What is the main cause of this type of error ?

Because, previously my function worked just fine and i haven't change a thing and suddenly this error popped up. Thanks in advance...

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Matt Fig 2012-10-12

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在 MATLAB Online 中打开

MATLAB is case sensitive. Target, target, tarGet, TarGet are all different things. If your function is named target, don't call it as Target.

clear all
Tar = 6;
TAR = 7;
tar = 8;
whos

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Thanks Matt, yes i realize that MATLAB is case sensitive. But i dont think i've overlooked that. Because my function worked great before and i haven't changed anything since. too bad my code is to long and has many function calls, quite reluctant to post it here. Any other suggestions ?

Walter Roberson 2012-10-12

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在 MATLAB Online 中打开

which -all Target

See if it is on your path.

Try executing

rehash

tarmizi adam 2012-10-12

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which -all Target

returns "C:\Program Files\MATLAB\R2009a\toolbox\eml\eml\@eml\target.m % eml method" in the command window.

'target.m' is not my function tough. the 'Target' that im using is from

fid = fopen('C:\Users\tarmizi\Documents\MATLAB\Feature Extraction   MSc\Target_Test.txt','r');
  Target = fscanf(fid,'%d');

is this the cause of the confusion ? how do i fix this ? do i have to change the 'Target' to another variable name..

tarmizi adam 2012-10-12

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i've changed the 'Target' to 'fileOpen' as below:

fid = fopen('C:\Users\tarmizi\Documents\MATLAB\Feature Extraction   MSc\Target_Test.txt','r');
  fileOpen = fscanf(fid,'%d');

now MATLAB produces the error:

Undefined function or variable "fileOpen".

the previous problem seems to show that MATLAB was confused between 'Target' and the target.m function. But now MATLAB says that "fileOpen" is undefined.

all the functions are placed in the same folder, so i don't think its a path problem.

Walter Roberson 2012-10-12

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Ah, okay then what it is telling you is that at the point where fileOpen is being used (not the point it is being initialized), fileOpen does not exist. We would need to see the code between the two points to explain what is going on.

tarmizi adam 2012-10-12

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在 MATLAB Online 中打开

The following is the code..

function TestNN(test_Feat,netName,net, TEST,featName)
test_Feat = test_Feat;
%=======Test the trained network with Testing features=====
Yt=sim(net,TEST);
%=========================================================
if length(test_Feat.testFeat.TEST)== 416
    fid = fopen('C:\Users\tarmizi\Documents\MATLAB\Feature Extraction MSc\Target_Test.txt','r');
    fileOpen = fscanf(fid,'%d');
elseif strcmp(test_Feat.Name,'TEST_F8.mat')==1
      fid = fopen('C:\Users\tarmizi\Documents\MATLAB\Feature Extraction MSc\PatternF8.txt','r');
      fileOpen = fscanf(fid,'%d');
end
disp('SAVE RESULT TO .txt FILE')
Answer = zeros(length(Yt));
 L = length(Yt);  %number of test pattern
 ans = 1;
    for m = 1:L
        max = 0.0; %0.0
       for n = 1:26   
           if (Yt(n,m)>= max)
             max = Yt(n,m);
             ans = n;
             Answer(m) = ans;
           end 
      end
    end  
T = Answer;
  match = 0;
for i = 1:numel(fileOpen) % change this value if length of Yt changes
          if (T(i) == fileOpen(i))
              match = match+1;
          end 
end
    RR = (match / L)*100; 
fid = fopen('C:\Users\tarmizi\Desktop\tryJa\result.txt','a');
fprintf(fid,'%s:',featName);
fprintf(fid,'{%s}->',netName);
fprintf(fid,'recognition: %.2f  \t',RR);
fprintf(fid,'Match: %.2f  \t',match);
fprintf(fid,'Total pattern: %.2f \n',L);
%}
   disp('END OF EVALUATION, CHECK THE ".txt" FILE GENERATED FOR RESULTS')
   fclose('all');