Struggling to store indexing variable as an array.

I am trying to store a list of file names which have been retrieved from a folder.

Any help would be appreciated; here is what I have so far:

File = zeros(1,10);
for i=1:10    
    File(1,i) = sprintf('%s%05d%s', 'A', i, '.dat');
end

I get the error message: "Subscripted assignment dimension mismatch."

I would like the files to be stored as:

File = [A00001.dat A00002.dat ... A0000N.dat]

Hopefully it is clear what I'm trying to achieve.

If I use the code:

File = zeros(1,10);
for i=1:10    
    File = sprintf('%s%05d%s', 'A', i, '.dat');
end

It runs; however, it only stores the final File name (in this case, "A00010.dat") rather than a 1x10 array of the first 10 File names.

Thanks

Answer 1

[Guillaume]

Each character of a string is one element of an array. So File = zero(1, 10) will only let you store 10 characters, not 10 strings.

Because all your strings are the same length, you could store all of them in a 2D char array, with each row a string, and each column one of the 10 characters.

filenames = zeros(10, 10);  %space for 10 strings of 10 characters
for row = 1:10
   filenames(row, :) = sprintf('%s%05d%s', 'A', row, '.dat');
end

%to access a string:
s = filenames(stringindex, :)

However, much better would be to store your strings in a cell array, where each string is an element of the cell array. It's much safer, strings can be different sizes, the above will error if a string is not exactly 10 characters:

filenames = cell(1, 10); %space for 10 strings of arbitrary length
for sidx=1:10    
   filenames{sidx} = sprintf('%s%05d%s', 'A', sidx, '.dat');
end

%to access a string:
s = filenames{stringindex}

Finally, note there is an undocumented/unsupported function (use at your own peril) that can replace the creating and filling of the cell array: sprintfc:

filenames = sprintfc('A%05d.dat', 1:10)

[steven]

filenames = cell(1, 10); %space for 10 strings of arbitrary length
for sidx=1:10    
   filenames{sidx} = sprintf('%s%05d%s', 'A', sidx, '.dat');
end

This worked perfectly, thanks for your help.