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When I use titlesec, hyperref, and algorithm2e together, sections after an \appendix are not numbered properly.


Compiling this gives the warning

pdfTeX warning (ext4): destination with the same identifier (name{section.1}) has been already used, duplicate ignored

Sure enough, the .aux file shows

\@writefile{toc}{\contentsline {section}{\numberline {1}foo}{1}{section.1}}
\@writefile{toc}{\contentsline {section}{\numberline {A}bar}{1}{section.1}}
  • Removing titlesec changes the second section.1 to appendix.1.
  • Removing algorithm2e changes the second section.1 to section.A.
  • Removing both changes the second section.1 to appendix.A.

Unlike last time, I tried all six permutations of the packages but had no luck.

Can this combination of packages be made to work?

share|improve this question
up vote 6 down vote accepted

It's always good to load hyperref last. (But you're right, that won't solve your problem.) I think the main source of the problem is algorithm2e. Based on this discussion (in German) here, it seems that there are a few possible solutions. The simplest two are:



after loading hyperref.




after loading algorithm2e.

\let\chapter\undefined % use this line
%\renewcommand*{\theHsection}{\thesection} % or this one
share|improve this answer
Thanks! It seems like the best solution (per a Google translate) is \let\chapter\undefined after loading algorithm2e. As you note, I should have been loading hyperref last, and indeed I normally would. I just happened to start with lexicographic ordering of the packages to make sure I didn't miss any of the 6 permutations. t, h, a was the 6th permutation. =) – TH. Apr 10 '11 at 1:13
Yes, that will work too. I read the post quite quickly and went for the first solution that worked. I'll adjust my answer. – Alan Munn Apr 10 '11 at 1:27

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