Modify a text file
94 views (last 30 days)
Show older comments
Hello everyone,
I have a .dat file like in the picture and I would like to modify I3 values (the last column). I can't use textscan since the beginning of the file has a different format.
Do you have any idea on how can I do this ?
3 Comments
Accepted Answer
Rik
on 3 Sep 2020
data=readfile(filename);
HeaderLines=9;
delta=rand(numel(data)-HeaderLines,1);%generate some random data for this example
for n=(HeaderLines+1):numel(data)
%store in temp variable
str=data{n};
%read the value, add something to it, and merge back
ind=strfind(str,' ');ind=ind(end)+1;%assumes you don't have a trailing space and the delimiter is a space
lastval=str2double(str(ind:end));
lastval=lastval+delta(n-HeaderLines);
str=sprintf('%s%.3f',str(1:(ind-1)),lastval);
%store back to array
data{n}=str;
end
%write back to file (overwrites the original)
fid=fopen(filename,'wt');
fprintf(fid,'%s\n',data{:});
fclose(fid)
17 Comments
Rik
on 9 Sep 2020
I would separate finding the value of the correction and using it. I also would not use i and j as variables. You might also consider using ismember and/or find. A possible optimization would be to convert the mcorrection and ncorrection arrays to double only once (so outside the loop).
So no, I don't see any 'bad programming' here.
More Answers (0)
See Also
Categories
Find more on Data Type Conversion in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!