"Track changes" in LaTeX

Question

I am writing a scientific paper with my collaborator. We have submitted a version to a journal and now we got a review from them, so we need to fix a few things. In Microsoft Word there is the option to "track changes", which displays the deleted text as crossed out and the new text bolded (if I remember the details correctly). Is there a way to achieve a similar result in LaTeX?

I was thinking to create a new file for the revised version and then write a script which would basically compare the two files and make the differences either bold or crossed out before sending it to latex. Is there a tool that already does it?

Answer 1

You can process your TeX files with the Perl program latexdiff that is included with most LaTeX distributions.

From the manual:

Briefly, latexdiff is a utility program to aid in the management of revisions of latex documents. It compares two valid latex files, here called old.tex and new.tex, finds significant differences between them (i.e., ignoring the number of white spaces and position of line breaks), and adds special commands to highlight the differences.

Answer 2

I have used the changes package in the past and I find it very useful. It has a key=value system so most of the things are customizable. You can define different authors and the changes are tracked depending on the id; here is a simple example (mostly from the manual).

\documentclass{article}

\usepackage{changes}
\usepackage{lipsum}% <- For dummy text
\definechangesauthor[name={Per cusse}, color=orange]{per}
\setremarkmarkup{(#2)}


\begin{document}
\lipsum[1-7]

This is \added[id=per,remark={we need this}]{new} text.
This is \added[id=per,remark={has to be in it}]{new} text.
This is \deleted[id=per,remark=obsolete]{unnecessary}text.
This is \replaced[id=per]{nice}{bad} text.

This is \added[remark={we need this}]{new} text.
This is \added[remark={has to be in it}]{new} text.
This is \deleted[remark=obsolete]{unnecessary}text.
This is \replaced{nice}{bad} text.


\listofchanges
\end{document}

And the nice thing is that if you supply the final option to the package declaration that is \usepackage[final]{changes} it clears the traces of changes made by the authors and respecting the last changes. See the replaced and deleted text for an example.

Answer 3

Latex documents are plain text. Therefore you can handle tracking changes for Latex documents using the same robust methods that millions of software developers have been using for decades!

Short description of how software developers track changes in their source code:

• keep the source in version control (git, svn, or whatever)
• use differencing software to see what changes are made in between each revision (diff, vimdiff, Beyond Compare)

Here is a screenshot of what a diff program looks like (in this case this is a stock photo from Beyond Compare's website):

(I actually don't use Beyond Compare. I prefer plain diff with vim which colorizes the diff.)

So whenever a change is made the change is saved in version control. And your version control keeps track of all changes. Allowing you to do things like: compare the two most recent versions, or compare the most recent with 5 versions back... or compare arbitrary version to arbitrary version. You have all the versions stored in version control!

Answer 4

For completeness sake, Adobe Acrobat Professional offers an excellent tool to compare PDFs. That tool has been heavily revised for v9 and now works extremely well for all sorts of text, including tables, font changes etc.

Some advantages over latexdiff:

• Can track changes in the bibliography
• Changed text is "overlayed", not crossed out or underlined, allowing for a cleaner document.
• All changes are stored as comments that can be exported.

Downside:

• Expensive
• Does not work with LuaTeX together with fontspec

Answer 5

You can simply create two commands for marking added and deleted text and display them as you wish. LyX features a change tracking mechanism, which is implemented in the source like this:

\PassOptionsToPackage{normalem}{ulem}
\usepackage{ulem}

\providecolor{added}{rgb}{0,0,1}
\providecolor{deleted}{rgb}{1,0,0}
%% Change tracking with ulem
\newcommand{\added}[1]{{\color{added}{}#1}}
\newcommand{\deleted}[1]{{\color{deleted}\sout{#1}}}

Whatever you mark with \added{...} will be displayed in blue and \deleted{...} in red and strikenthrough. If such a functionality would be just enough for you, in the final compilation of your document simply redefine \added to plain text passing and \deleted to be omitted. I.e., the following snippet should do:

\newcommand{\added}[1]{#1}
\newcommand{\deleted}[1]{}

Note, these are commands, so you cannot use that for too long text snippets. If your changes are more like blocks of text, take a look at the versions package at CTAN.

Answer 6

If you need to mark the changes in the \LaTeX source, the package http://trackchanges.sourceforge.net/TrackChanges is very helpful. It comes with a couple of python programs for globally accepting or rejecting changes as well.

Answer 7

I created revdiff to build diff versions of my papers before sending them to reviewers. They have told me several times that the result was really helpful. Hope it can be useful for you.

Find it here

Answer 8

Most answers focus on one part of the question which is how to compare two versions of a document. The other part being how to keep track of changes in the document.

As it has been underlined by other answers, .tex files are actually plain text files containing the latex markup language. It can be handled using classical software development tools.

So for comparison of versions you can use diff tools.

And for keeping track of multiple versions you can use a Revision control software. I would recommend git or mercurial. Those software typically embed diff tools to check differences between various revisions of the document. The main advantage over a simple copy paste of the .tex file is that you can keep track of the whole history of the document: what changes you made 2 weeks ago ?

It is also great for multiple author writing as revision control software can keep track of who made what change as well as merge changes of automagically !

Answer 9

For the sake of completeness, the accepted answer to an even older, similar question on Stack Overflow mentions the package todonotes, which offers "MS Word-style" commenting, and more, for those reviewers who are comfortable enough to edit the actual LaTeX code. Haven't used it myself, but it looks pretty solid. The documentation is updated as of July 2018, and provides nice examples.

Answer 10

If you use pdflatex, there is an Acrobat (Professional) function to compare two PDFs. For a high-level overview on the major differences, it works surprisingly well IMHO.

Answer 11

Maybe this is not a direct answer to your question, but I still suggest you try my package debate. It helps you organize a discussion between reviewers inside your document:

\documentclass{article}
\usepackage{debate}
\begin{document}
I think apples are tastier
  \debate[jeff]{I don't think it's true!}
  \debate[anna]{It is indeed true!}
than pears!
\end{document}

When you are ready to make them all invisible, just use \usepackage[hide]{debate}

Answer 12

You can also use the trackchanges package (link), which is very straightforward to use. The only thing to do is adding the trackchanges.sty file in the root of the LaTeX project and start adding your changes:

...
\usepackage[margins]{trackchanges}
...

\addeditor{sampleEditor}

My text \add[sampleEditor]{new text}.
My text \remove[sampleEditor]{removed text}.

Answer 13

I think unfortunately there is no way to work with an advisor that knows latex but that likes MS Word track-changes option so much that you need to pass him directly the pure latex .tex file and he works with word on it...