Extract value MATLAB - matlab

Question

I need to extract the first value of the following code:
3.43099,70.8539,91.701,FAIL
The file has the '.sol' extension, but it can be read in notepad or Matlab.
I just want to know how to to read in all *.sol files in a folder and how to write the extracted value in a text file.
Thanks a lot, i would be grateful.
NEW
ita='"';
for i=1:size(z,2)
word_to_replace=input('Replace? ','s');
tik=input('Replacement? ','s');
coluna=input('Column? ');
files = dir('*.txt');
for i = 1:numel(files)
if ~files(i).isdir % make sure it is not a directory
contents = fileread(files(i).name);
fh = fopen(files(i).name,'w');
val=num2str(z(i,coluna));
word_replacement=strcat(tik,val,ita);
contents = regexprep(contents,'word_to_replace','word_replacement');
fprintf(fh,contents); % write "replaced" string to file
fclose(fh) % close out file
end
end
end
Many thanks

Answer 1

File extension does not make a difference as to what MATLAB can "read", use the fileread command to load in the file and parse its contents. You can then split on commas, since it looks like it is comma separated
files = dir('*.sol');
fh = fopen('outFile.txt','w');
for i = 1:numel(files)
if ~files(i).isdir % make sure it is not a directory
contents = fileread(files(i).name);
parts = regexp(contents,',','Split');
fprintf(fh,[parts{1},'\n']);
end
end
fclose(fh)
This should do what you want. It will find all files in the current directory with the .sol extension, loop through all of them, grab the first value, and write it out to a text file.
Find and replace
Finding and replacing is relatively simple as well. You can do the same looping, read the file contents, run a replacement, and then rewrite that out to the same file.
files = dir('*.sol');
for i = 1:numel(files)
if ~files(i).isdir % make sure it is not a directory
contents = fileread(files(i).name);
fh = fopen(files(i).name,'w'); % open handle to same file just read for overwriting
contents = regexprep(contents,'toReplace','replacement'); % do string replacement
fprintf(fh,contents); % write "replaced" string to file
fclose(fh) % close out file
end
end