Question

this question about matlab:
i’m running a loop and each iteration a new set of data is produced, and I want it to be saved in a new file each time. I also overwrite old files by changing the name. Looks like this:

name_each_iter = strrep(some_source,'.string.mat','string_new.(j).mat')

and what I#m struggling here is the iteration so that I obtain files:
…string_new.1.mat
…string_new.2.mat
etc.

I was trying with various combination of () [] {} as well as ‘string_new.’j’.mat’ (which gave syntax error)

How can it be done?

Answer 1

For creating a name based of an already existing file, you can use regexp to detect the ‘_new.(number).mat’ and change the string depending on what regexp finds:

original_filename = 'data.string.mat';
im = regexp(original_filename,'_new.\d+.mat')
if isempty(im) % original file, no _new.(j) detected
    newname = [original_filename(1:end-4) '_new.1.mat'];
else
    num = str2double(original_filename(im(end)+5:end-4));
    newname = sprintf('%s_new.%d.mat',original_filename(1:im(end)-1),num+1);
end

This does exactly that, and produces:

    data.string_new.1.mat
    data.string_new.2.mat
    data.string_new.3.mat
    ...

    data.string_new.9.mat
    data.string_new.10.mat
    data.string_new.11.mat

when iterating the above function, starting with ‘data.string.mat’