textscan desnt work in forloop

okay so this is the coad, the text scan fuction works and the whole coad runs without the for loops, but when addiing the forloops the coad doesn work the error i m getting is :

Error using textscan

Invalid file identifier. Use fopen to generate a valid file identifier.

Error in forllooptest (line 7)

c = textscan(fid,'%f %f %f %f %f %f %f','HeaderLines', 12);

for i = 0
    for j = 0
        for k = 0
            for l = 0:8
                b = sprintf('cl%d%d%d%d.txt',i,j,k,l);
                fid = fopen(b);  
                c = textscan(fid,'%f %f %f %f %f %f %f','HeaderLines', 12);
                fclose(fid);
                %delete(cl.txt);
                % Separate boundary points
                d = c{:,3}(1,:);
                %if (exist(saveFlnmAF,'file'))
                %delete(saveFlnmAF);
                %end
                g(i) = d
           
                [val, idx] = maxk(g,5)

            end
        end
    end
end

Please does someone know how to correct this. thank you

[KALYAN ACHARJYA]

Is this complete code?

[Divya Patel]

Yes sir!, What am I missing,

[Divya Patel]

idk what seems to be the problem with textscan or is it the for loop?

[Divya Patel]

  
       XFOIL         Version 6.99
  
 Calculated polar for: NACA 0001                                       
  
 1 1 Reynolds number fixed          Mach number fixed         
  
 xtrf =   1.000 (top)        1.000 (bottom)  
 Mach =   0.000     Re =     0.271 e 6     Ncrit =   9.000
  
   alpha    CL        CD       CDp       CM     Top_Xtr  Bot_Xtr
  ------ -------- --------- --------- -------- -------- --------
   0.000  -0.0001   0.00531   0.00015   0.0000   1.0000   1.0000
   0.000  -0.0001   0.00531   0.00015   0.0000   1.0000   1.0000
   0.000  -0.0001   0.00531   0.00015   0.0000   1.0000   1.0000

here is the file..file name cl0001.txt..and so one to cl0008.txt

[per isakson]

Does cl0000.txt exist?

[Divya Patel]

Ohh...let me check if that works..it doesn't exist!!!

[Divya Patel]

Thank you the whole issue is resolved. I was just stupid to not see that!

[Divya Patel]

i have a follow up question!, how would i tell it to skip that fild read if the line is empty, for textscan so it donest give me that error!

[Walter Roberson]

if fid < 0; continue; end

Answer 1

[Raunak Gupta]

Hi,

Hope the file identifier error is resolved. For the follow up question you may read the file from textscan even if it is empty and then can check if the resultant cell array is empty or not. If it is empty, then you may simply skip that iteration in the loop.

For checking if the cell array is fully empty you may use following

number = sum(cellfun(@isempty,c) == 1)

This number should be zero for fully empty text file.