How do I import files from a folder one at a time

I have many files (>250) named '1.txt','2.txt',etc. If I'm reading them using

Filelist = dir('*.txt')

The information is getting altered in the program (I don't know how). So, I want to read files one by one. like

   Filelist = dir('1.txt')

and so on... I can't figure out how to change the file name from 1.txt to 2.txt... after I have read the first file. Kindly help.

Answer 1

[Walter Roberson]

If the information is getting altered by the program, make a backup copy of the variable?

See https://www.mathworks.com/matlabcentral/answers/404204-how-to-import-data-from-multiple-files-into-matlab#comment_575446 for example code.

[John Doe]

I meant to say, somehow matlab is loading wrong values. The value in txt is 3.458 but matlab shows it as 1.3151 (there are many such values in all files) if I use *.txt but this doesn't happen if I load files one by one.

[Walter Roberson]

As far as MATLAB is concerned, there is no difference between

     Filelist = dir('1.txt')

and

   thisfile = '1.txt';
   Filelist = dir(thisfile)

But do be careful if your actual work involves multiple directories: you should be careful to use fullfile() to form proper file names.

[John Doe]

Thank you, sir. Your answer has been really helpful.

Now, I'm doing this:

 for i=1: number of files to be read
     ext = '.txt';
     name = strcat(num2str(i),ext);
     filename = dir(name);
     .....{working on the specific loaded file}
 end

It works fine. Computation increased a bit because of the 'for loop' but works just fine.