Search and replace variable - matlab

Question

I have some 100+ conf files that I am working. I need to find and replace various variable for all these files. For example, I'd like to find the line
Amplitude = 100; and replace it to: Amplitude = 200; for all files.
I've searched in online and found the solution only for one file. I'm looking for a way to do that in Matlab. Any ideas?

Answer 1

If these files can be opened as normal text files then I wouldn't use matlab. Notepad++ has an replace option for as many files as you want, just make sure, you test it out on a backup file first. so have it find "Amplitude = 100" and replace that by what you want.
To see how to do it, look here:
how-to-find-and-replace-lines-in-multiple-files
If you can't do that, put all the files in the same directory (you have to do this anyway). Then load the files in matlab with that directory and run a for loop. However it might be a bit slow./
Basically if you can do 1 file, you could do all of them with a for loop.
If you need help with that I show can some code I used before.

Answer 2

Well, Matlab solution would be to (recursively) open all files in the directory. Here I show example for non-recursive solution (it does not check subfolders), though it would be easy enough to modify it to search subfolders too if needed:
d = dir(yourPath);
for i = 1 : length(d)
if ~(d(i).isdir)
%d(i) is file.
replaceSingleFile(strcat(d(i).folder, d(i).name));
end
end
As you say, you already know how to do replace for a single file, though to have complete answer here, solution could be along the lines (in the function replaceSingleFile).
F = fopen(fileYouWantReplaced);
i = 1;
while (~feof(F))
L = fgetl(F);
L = strrep(L, 'Amplitude = 100;', 'Amplitude = 200;');
Buf{i} = L;
i = i + 1;
end
fclose(F);
%now just write all Buf to the same file again.
F = fopen(file..., 'w'); % Discard contents.
for i = 1 : numel(Buf)
fprintf(F, '%s\n', Buf{i});
end
fclose(F);