# Conflict between UTF8 and UTF-CJK

I appear to be having a conflict with font encodings. I am currently using LyX 2.1.1 (under Linux Mint 17). I have Chinese text scattered throughout most chapters, but I receive the following error when exporting to PDF:

Use of \@chapter doesn't match its definition

...ing{latin9}Pottery Production at Huizui I}


To be specific, as you can see, only the chapter title seems to generate this error. When I change the encoding to UTF8 (Document > Settings > Language), I then get an error with the Chinese text:

...in Ancient China'' {[}\begin{CJK}{GB}{}
Ŵչо\end{CJK... The control sequence at the end of the top line of your error message was never \def'ed.


This was not an issue under LyX 2.0.6, though at the time I used a cumbersome ERT inset; under 2.1.1 I just change the Language to "Chinese" and change the input on my computer to Chinese as well.

Clearly, the issue seems to stem from something with \@chapter, but I don't know why this is suddenly a problem.

Unfortunately, I don't know if I can provide a MWE: this is a multi-chapter dissertation with master and child docs. Still I'm hoping some folks have some ideas that I can try out.

If there are any enterprising folks that want me to send the document to look at, I am happy to do so!

Edit1:

Looking at the source, here is the bit causing trouble:

\usepackage{CJKutf8}

\begin{document} \begin{CJK}{UTF8}{}%

\chapter{\end{CJK}\inputencoding{latin9}Pottery Production at Huizui I}

\inputencoding{latin9}\label{chap:Chapter-4}In this chapter I analyze and discuss the primary data collected from the Huizui site and the


And later, when Chinese is used:

...by Li Wenjie A Study of
the Pottery-Making Technology in Ancient China'' \begin{CJK}{GB}{}中国古代制陶工艺研究\end{CJK}\inputencoding{latin9}
using pottery in the National History Museum collection.


As you can see, the encodings seem to switch back and forth correctly, though the bit of code above

\begin{CJK}{UTF8}{}%

\chapter{\end{CJK}


Seems strange to me because \chapter ends up "as" CJK.

Edit2:

Actually, that last comment (below) is not entirely true; that unusual coding is not present when I change the encoding (Document>Settings>Language) to "Unicode (utf8)" rather than "Unicode (CJK)(utf8)". However, then the CJK text throws errors as "not found", which is still odd because in the preamble it has this code:

\usepackage[utf8]{inputenc}
\usepackage{CJKutf8}


which I would think covers the CJK text. I think LyX adds this line because it detects that I've used "Chinese" in the document.

Edit 3:

I have now tried a work-around based on egreg's answer below, and changed the beginning code to:

\makeatother

\begin{document}
\begin{CJK}{UTF8}{}%
\end{CJK}\inputencoding{latin9}\chapter{Pottery Production at Huizui I}

\label{chap:Chapter-4}In this chapter I analyze and discuss the primary
data collected from the Huizui site and the archaeometric analysis...


Here, \begin{CJK} is not incorporated into \chapter, but now I get an error for the Chinese text even though I have the encoding set to "Unicode (CJK)(utf8)"!! Makes me think it is actually a problem with the CJK font family as egreg points out. Not sure why mine is set to {GB} rather than {gbsm} which worked previously.

• \@chapter complains because something is putting the [ at the start of its first argument in braces. You can see such a [ in your second snippet. But it is not possible to see under which circumstances lyx does it and if it is related to the chinese. – Ulrike Fischer Jul 25 '14 at 7:40
• Thanks Ulrike, that's a start. I include the Chinese text in braces [Zhongguo] to set it apart from conventional asides in parentheses. Could this be causing the problem? Will check it out. – charles Jul 25 '14 at 16:51
• ***Okay, removing braces and changing encoding to UTF-CJK gives same error as my first example. – charles Jul 25 '14 at 16:55
• You shouldn't start \begin{CJK} before \chapter and end it in the argument of \chapter: this will leave unbalanced groups. – egreg Jul 25 '14 at 17:45
• @scottkosty Was thinking I needed to do just that. Thanks for the link. – charles Jul 26 '14 at 13:35

My impression is that LyX is overzealous in doing encoding switching. But

\begin{CJK}{}
\chapter{\end{CJK}\inputencoding{latin9}Something}


is simply wrong code that can't work with any trick whatsoever.

If you plan to use CJKutf8, the document encoding should be UTF-8, of course, and not Latin-9. How to set this up for LyX is beyond my knowledge. The following code works.

\documentclass{book}
\usepackage[utf8]{inputenc}
\usepackage{CJKutf8}

\begin{document}

\chapter{Pottery Production at Huizui I}\label{chap:Chapter-4}

In this chapter I analyze and discuss the primary data collected
from the Huizui site and the \dots

\dots\ by Li Wenjie A Study of
the Pottery-Making Technology in Ancient China''
\begin{CJK}{UTF8}{gbsn}中国古代制陶工艺研究\end{CJK}
using pottery in the National History Museum collection.

\end{document}


Note the font family in the argument to \begin{CJK}.

• The zealous encoding by LyX does seem to be the problem. I cannot understand why it keeps invoking {latin9}, as you'll notice in Edit 1 that after the CJK text, it "switches" back to {latin9}. Must be one of the settings – charles Jul 25 '14 at 20:38
• @charles I once tried LyX. After no more than half an hour, there was no longer any trace of it on my machine. – egreg Jul 25 '14 at 20:47
• Yes, I am becoming increasingly frustrated by it, too. I have had to use a fair amount of ERT to format things the way I want. Also, still no support for biblatex, so I cannot use Chinese in my references list... – charles Jul 25 '14 at 21:03