Regular Expression to append a string in text file

Here are some sentences from Text File.

hi where are you going.
hi how are you doing.
how are you.
hi where are you at this moment.

i want to replace '.' with '</s>'

so i am writing the following expression

1. fid = fopen('Text_File.txt','w');
2. f=fread(fid,'*char')';
3. f = regexprep(f,'\.','</s>')

it is working perfectly BUT, i want to append a starting symbol at the beginning of sentences also that is '<s>', for that that i am using following one.

1. f = regexprep(f,'^[]','<s>');

but it is not working what wrong i am doing.

PLZ answer thanks in advance.

Answer 1

[Cedric]

Here is a simple and funny solution:

 txt = regexprep( fileread('Text_File.txt'), '([^\n\r]+)', '$1' ) ;