how to process the data in a file and repeat the procedure for different folders?

I have a set of files called "p" under the folder of "surface->0.1 (folder named by time steps)->patchgorund->scalarField". As you can see in the attachment, in the file "p" there are 400 data inside bracket. Now I have to change those data by minus a number, for example, p-1000. Then repeat this procedure for each folder (0.1, 0.2, 0.3.....->patchgorund->scalarField->p). Do you have any ideas?

[Stephen23]

"Do you have any ideas?"

Loop over the folders, import the file data, change the data, export the data to file.

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

[kimy]

thank you.

Answer 1

[Wan Ji]

Here is an example for reading files and changing its content

q = 0.1:0.1:2;
folder = arrayfun(@(i)['surface\',num2str(q(i)),'\patch_ground\scalarField\p'],1:numel(q),'uniform',0);
for i = 1:1:numel(fid)
    s = fileread(folder{i});
    ch = s;
    s1 = strfind(ch,'(');
    s2 =  strfind(ch,')');
    data = str2num(ch(s1+1:s2-1)) - 1000; % minus 1000
    ss = num2str(data','%f\n');
    ch = [ch(1:s1), ss, ch(s2:end)];
    fid = fopen(folder{i},'wt');
    fprintf(fid,'%s',ch);
    fclose(fid);
end

[kimy]

Thanks. I modified the code and now it works:

q = 0.1:0.1:2;
folder = arrayfun(@(i)[num2str(q(i)),'\patch_ground\scalarField\p'],1:numel(q),'uniform',0);
for i = 1:1:numel(folder)
    s = fileread(folder{i});
    ch = s;
    s1 = strfind(ch,'(');
    s2 =  strfind(ch,')');
    data = str2num(ch(s1+1:s2-1)) + 1000; % minus 1000
    ss = num2str(data','%f\n');
    ch = [ch(1:s1), ss, ch(s2:end)];
    fid = fopen(folder{i},'wt');
    fprintf(fid,'%s',ch);
    fclose(fid);
end

[kimy]

I need to separate numer and bracket in separate line. Should I add '\n' this in the code? such as,

ch = [ch(1:s1),'\n', ss, '\n',ch(s2:end)];

[Wan Ji]

If neccessary, i believe those you have modified, because you are the practitioner. For example, if the output file named 'p' conflicts with your OpenFoam software, then you need to use '\n', in order not to make mistakes.

[kimy]

However, what I got is like below if I added '\n', which seems to me '\n' was regarded as a string in this case.

400
(\n195910.263000
195908.263000
......

[Wan Ji]

you can use newline instead ch = [ch(1:s1),newline, ss, newline,ch(s2:end)];