I want to put numbers from 1 to 8 after the file name using 'for loop' and save this file name as a variable.

I want to put numbers from 1 to 8 after the file name using 'for loop' and save this file name as a variable.

fn_1 = file name1.txt

fn_2 = file name2.txt

fn_3 = file name3.txt

...

fn_8 = file name8.txt

In this way, I want to store each of them in a variable.

What should I do?

C:\Users\file name.txt The file name.txt file exists in that path.

This is the code I made by me.

for num = 1 : 8

disp(sprintf('C:\\Users\\file name%d.txt'));

end

I've only printed out file names (1 to 8).

Answer 1

[Stephen23]

"In this way, I want to store each of them in a variable."

That would be a very inefficient use of MATLAB. MATLAB is designed to use arrays. You should use arrays:

P = 'C:\Users';
V = 1:8;
T = compose("file name%d.txt",V(:))

T = 8×1 string array
    "file name1.txt"
    "file name2.txt"
    "file name3.txt"
    "file name4.txt"
    "file name5.txt"
    "file name6.txt"
    "file name7.txt"
    "file name8.txt"

T = fullfile(P,T)

T = 8×1 string array
    "C:\Users/file name1.txt"
    "C:\Users/file name2.txt"
    "C:\Users/file name3.txt"
    "C:\Users/file name4.txt"
    "C:\Users/file name5.txt"
    "C:\Users/file name6.txt"
    "C:\Users/file name7.txt"
    "C:\Users/file name8.txt"

If you want to import that file data, use something like this:

N = numel(V);

C = cell(1,N);

for k = 1:N

F = sprintf('file name%d.txt',V(k));

C{k} = readmatrix(fullfile(P,F)); % or READTABLE, etc.

end

See also: https://www.mathworks.com/help/matlab/import_export/process-a-sequence-of-files.html

[niniki]

Thank you very much for your help. You are a genius.

[niniki]

@Stephen ,

Hello, thanks to you, it's been solved well.

I have one question, so I leave a comment again.

I understand that V(:) stores T as a column vector, but I wonder why the numbers from 1 to 8 are included in the %d part.

I'm confused because I only know that things like %d%f specify text format.

Can you explain it?

[Stephen23]

"I understand that V(:) stores T as a column vector"

(:) indexing returns a column vector, which is then provided as the 2nd input to COMPOSE.

"but I wonder why the numbers from 1 to 8 are included in the %d part."

COMPOSE uses the format string (1st argument) to convert the other inputs into the output text.

"I'm confused because I only know that things like %d%f specify text format. Can you explain it?"

%d is also used here to specify the text format: it tells COMPOSE how we want the input numbers to look like in the output text. The rest of the format string is literal.

Answer 2

[Arif Hoq]

try this:

C=cell(8,2);
j = 1;
for m = [1:8]
    C{m,1}=strcat('fn','_',num2str(j));
    C{m,2}=strcat('file name',num2str(j),'_','txt');
    j = j+1;
end
out=string(C)

[Stephen23]

Not very robust. Consider what would happen if the numbers change to [2,3,6,7,8].

• The variable m should not be used as the index: the values from the vector should be used to generate the filenames, then if the vector changes, the code would still work (well, mostly... it still needs NUMEL or similar).
• The variable j should be used as the index. Then it would correctly allocate to the output cell array, regardless of the vector values.
• Replace slow STRCAT with much faster SPRINTF.
• Those square brackets are completely superfluous. Get rid of them.

[Arif Hoq]

thank you very much stephen..