How can I split a file at defined intervals into multiple files?

Hi Matlab Community,

I am trying to split a file (see example included) at defined line intervals, e.g. every 4th line and safe the sequence of lines in a new file with increasing numbers in the filename. For example, I am trying to split a file with 40 lines of text into 10 files with 4 lines each and name the resulting files 1.txt, 2.txt, 3.txt. etc.

I have not included code as my attempts have not resulted in anything useful.

I am very grateful for any help and suggestions how to achieve this.

Thank you,

Max

Answer 1

[Wan Ji]

s = fileread('test.txt'); % read files to string s
k = find(s==newline); % find newline position
s = mat2cell(s,1, diff([0,k(4:4:end-1),numel(s)])); % split with every 4 newlines
fid = arrayfun(@(i)fopen([num2str(i),'.txt'], 'wt'),1:1:numel(s)); % get the fid
arrayfun(@(i)fprintf(fid(i),'%s',replace(s{i},newline,'')),1:1:numel(s)); % write to 1.txt 2.txt...
arrayfun(@(i)fclose(q(i)),1:1:numel(s));% close files

[Max90]

Hi Wan Ji,

Thanks a lot for your answer. The basic concept of what i am trying to achive works with your code. Is there a way to keep the original line format, because I think the mat2cell function puts the four original lines into one line in the split files:

1.txt:

Here is some textHere is some text aswellHere is some textHere is some text aswell

Should look like:

Here is some text

Here is some text aswell

Here is some text

Here is some text aswell

Thanks a lot,

Max

[Wan Ji]

Try this, maybe it is a matter of matlab version, I have tested alright with matlab 2020a

s = fileread('test.txt'); % read files to string s
k = find(s==newline); % find newline position
s = mat2cell(s,1, diff([0,k(4:4:end-1),numel(s)])); % split with every 4 newlines
fid = arrayfun(@(i)fopen([num2str(i),'.txt'], 'wt'),1:1:numel(s)); % get the fid
arrayfun(@(i)fprintf(fid(i),'%s',s{i}),1:1:numel(s)); % write to 1.txt 2.txt...
arrayfun(@(i)fclose(q(i)),1:1:numel(s));% close files

[Wan Ji]

I'd like to have my answer accepted if this code helps you. many thanks in advace

[Max90]

Hi,

Thanks a lot. It worked now!

Max