\lyxframeend
                 {}\lyxframe{Outline}
The control sequence at the end of the top line
of your error message was never \def'ed. If you have
misspelled it (e.g., `\hobx'), type `I' and the correct
spelling (e.g., `I\hbox'). Otherwise just continue,
and I'll forget about whatever was undefined.

After comparing my document to example (working) beamer documents I’ve found out that you must have an EndFrame command after your last frame.Too bad it wasn’t documented anywhere I’ve found as this little thing drove me crazy.

At first, I’ve tried to use the English dash and en-dash but result weren’t satisfactory. Both of them were too light and positioned too low to be used in an Hebrew text written in the Culmus fonts (see screenshot).

So finally, I’ve decided to write a simple macro to emulate a Kav-Mafrid for the David font.

\newcommand{\dd}{\lower0.17em\hbox{-\kern-0.13em-}}

The command works by kerning two Hebrew, Maqaf’s, together (with a slight overlap to adjust width), and lowering their position to the middle of the line.

In the following screensot the first line features the Frank Ruehl font and it\’s Maqaf and Kav-Mafrid. The second line featured the david font with a Maqaf and the missing Kav-Mafrid ligature. The third line features the David font with English dash and en-dash. The last line uses David with the regular Maqaf and the \dd{} macro.

Different dash examples

As it can be seen, the \dd{} macro does provide a good alternative for the Kav-Mafrid. However this solution isn’t perfect. One can improve the macro by detecting if the Kav-Mafrid ligature is present in the current font and if so, use it instead of the kerned one. This would enable one to use the macro and safely switch fonts, knowing he will always get the best Kav-Mafrid possible.

The problem is that because TeX doesn’t store information regarding the direction of text inside the dvi, RTL text is actually stored in reverse. When a link is inserted in such text, the command to start the link ends up after the command to end the link, which is problematic. When trying to compile such document with pdfTex it throws errors like:

! pdfTeX error (ext4): pdf_link_stack empty, \pdfendlink used without \pdfstart

On the otherhand XeTeX behaves a little nicer and compiles the document, but the wrong parts of the text are marked as links.

My workaround basically changes the order of the start and end link commands. Thus, in RTL text the commands get reversed and actually end up in the correct order. The workaround doesn’t support links spanning multiple lines and color links (although link border is supported). Further work needs to be done in order to support links in the table of contents. I could get it to work only in LTR mode (which isn’t good). You should insert the following code to your preamble in order to enable the workaround.

\makeatletter
\def\hyper@link#1#2#3{%
  \if@rl
    \setLR
      \begingroup
      \hyper@linkend
        #3
      \hyper@linkstart{#1}{#2}
    \setRL
  \else
    \hyper@linkstart{#1}{#2}
        #3
    \hyper@linkend
  \fi
}
\makeatother

I’ll also note that in order to generate correct pdf bookmarks (not in gibberish), you should set unicode=false in the hyperref’s options.

You can find a working example bellow (and the corresponding PDF output here).

\documentclass{article}
\usepackage{fontspec}
\usepackage{xunicode}
\usepackage{bidi}
 
\usepackage[unicode=false,
 bookmarks=true,bookmarksnumbered=false,bookmarksopen=false,
 breaklinks=false,pdfborder={0 0 1},backref=false,colorlinks=false]
 {hyperref}
 
\makeatletter
\def\hyper@link#1#2#3{%
  \if@rl
    \setLR
      \begingroup
      \hyper@linkend
        #3
      \hyper@linkstart{#1}{#2}
    \setRL
  \else
    \hyper@linkstart{#1}{#2}
        #3
    \hyper@linkend
  \fi
}
\makeatother
\setromanfont{Times New Roman}
 
\begin{document}
\setRL
\title{בדיקה}
\author{גיא רוטנברג}
\date{}
\maketitle
\pagebreak{}
 
\section{סעיף ראשון}\label{testlabel}
\subsection{תת-סעיף ראשון}\label{testlabel2}
 
לה לה
 
לי לי
 
לו לו
 
\pagebreak{}
\section{סעיף שני}
\subsection{תת-סעיף ראשון}
 
לה לה
 
\subsection{תת-סעיף שני}
 
לי לי
חלק \ref{testlabel}
אבגד
\hyperref[testlabel2]{בדיקה ארוכה}
 
\setLR
This is a test for LTR links. See section \ref{testlabel} and \hyperref[testlabel2]{long label}.
\end{document}

For sometime before letting go of the issue, I’ve tried to correct the direction of the label. It could have been fixed by marking the float as English text in LyX (I use it for editing Hebrew papers, as it makes editing multi-lingual texts easy), effectively adding \selectlanguage{english} before the \begin{algorithm} line. However, it resulted in display mess in LyX and some LaTeX errors when compiling (also it seemed LaTeX could complete the first pass).

Today, I’ve decided to tackle and solve the problem for a new paper I’m writing. After searching a bit for a way to override the Algorithm environment label, I’ve found a general way to override a float label in LaTeX:

\floatname{floatname}{floatlabel}

So for our case it would look like this:

\floatname{algorithm}{אלגוריתם}

You should put it in your LaTeX preamble (Documents->Settings in LyX). This neatly fixes the problem (see screenshot below).

To my surprise, Graphviz (and especially the dot utility) turned out to be the (almost) perfect tool for the job. It lets you describe the graph in a simple text-based way, and it handles the graph layout by himself. This is somewhat like LaTeX but for graphs (you concentrate on content not layout).

My Finite Automata needed no manual tweaking and resulted in a very nice graphs. For more complicated State Machines it’s sometimes necessary to do some manual tuning. The commands I found most useful to tweak the graph were:

• Grouping nodes to be in the same level – { rank="same"; "q1"; "q2"; "q3"}. The other options for rank can affect how the group is positioned relative to the other nodes in the graph (source, above all, sink bellow all).
• Adding weight to edges – q1 -> q2 [weight="10"]. This affects the cost of strecting the edge. The higher the weight the straighter the edges will be.
• Adding invisible edges – q1 -> q3 [style="invis"]. This allowed me to control the order of the nodes in the same rank (height).

Last but not least Graphivz can generate the graphs in variety for formats including eps, pdf and svg (which allows post-processing with inkscape).

LaTeX Error: Command \textquotedbl unavailable in encoding HE8

This could be solved by adding the following line to your LaTeX preamble:

\let\textquotedbl="

This line will define the \textquotedb to be the double quotation mark, and the document will compile look the same as it looked in older versions of LyX.

The general macro is the \relat. It takes two arguments, the relation and an expression where the relation takes place (the “at”). The equality-at macro, \eqat is a specific case of \relat. I’ve created it because it is commonly used and only requires passing the “at” argument.

Here is the LaTeX code for the macros.

\newcommand{\relat}[2]{\mathrel{\bigg|_{\mathrlap{#2}}\mathrlap{#1}\hphantom{{}_{#2}}}}
\newcommand{\eqat}[1]{\mathrel{\bigg|_{\mathrlap{#1}}\mathrlap{=}\hphantom{{}_{#1}}}}

This is a basic example of how to use the macros. It should also give you an idea how they look.

documentclass{article}
\pagestyle{empty}
\usepackage{mathtools}
 
\newcommand{\relat}[2]{\mathrel{\bigg|_{\mathrlap{#2}}\mathrlap{#1}\hphantom{{}_{#2}}}}
\newcommand{\eqat}[1]{\mathrel{\bigg|_{\mathrlap{#1}}\mathrlap{=}\hphantom{{}_{#1}}}}
 
\begin{document}
 
\[
\Delta=\left[\begin{array}{cc} P & Q\\ f' & g'\end{array}\right]
\eqat{\Gamma}
\left[\begin{array}{cc} -2t & 4t\\ 1 & -2\end{array}\right]
\]
\[
\cos x \relat{\leq}{x=\frac{\pi}{3}} \frac{\sqrt{@}}{2}
\]
 
\end{document}

And the output for the example is

Package amsmath Error: \begin{split} won't work here.

I was using LyX, so I’ve assumed that it would generate the correct syntax for this environment. But the error clearly said that the \begin{split} was used wrong. I’ve went through the user’s guide for the amsmath package and rechecked the syntax. The document has a very handy section that contain common error messages and explanations. I was happy to find out that the error I got was documented there. Unfortunately, the explanation only confirmed that LyX generated the appropriated code for the split environment.

At this point, I’ve decided to export the document to a LaTeX file and manually tweak it till I find a solution. I’ve removed everything from the document apart from some Hebrew text and the split formula. I’ve suspected this error had to do with the Hebrew, as nobody else reported errors using split to the LyX mailing list. I’ve remembered that someone mentioned to me once that LaTex is very sensitive to the order the packages are added. So I’ve started to play with the order and moved the \usepackage statements around. When I’ve put the \usepackage{babel} above the \usepackage{amsmath} the document suddenly compiled fine.

Some further testing showed that in order for the split environment to work properly in an Hebrew document the babel package must be included before amsmath and any other package that depends on it (like mathtools).

Getting things to work back in LyX was a bit more tricky. LyX automatically adds the babel package after the LaTeX preamble, and by default it adds the amsmath when needed, but it does so before the LaTeX preamble. This, as you can see, results in the \usepackage{amsmath} appearing before the \usepackage{babel}. The solution had to override the placements of both statements.

The first step is to go to Document->Settings->Math Options and uncheck both “Use the AMS math package automatically” and “Use the AMS math package”. This won’t prevent you from using any to the amsmath package feature if you include it manually (like we will do). The next step is to go to Documents->Settings->LaTeX Preamble, and insert directly at the top of the preamble the following two lines:

\usepackage{babel}
\usepackage{amsmath}

Now the Hebrew document will compile fine even if you use the amsmath’s split environment. Note that LyX will add \usepackage statement for for babel after the preamble despite the fact you already have one. But don’t worry, LaTeX will ignore that second statement and no harm will be done.

\newcommand{\explain}[2]{\underset{\mathclap{\overset{\uparrow}{#2}}}{#1}}
\newcommand{\explainup}[2]{\overset{\mathclap{\underset{\downarrow}{#2}}}{#1}}

This macros add the explanation below and above the formula.
The first argument is the relation (actually it can be anything) that needs be explained, for example =. The second argument is the actual explanation.

The macros depend on the mathtools package by

Example

\documentclass{article}
\usepackage{mathtools}
\makeatletter
 
\newcommand{\explain}[2]{\underset{\mathclap{\overset{\uparrow}{#2}}}{#1}}
\newcommand{\explainup}[2]{\overset{\mathclap{\underset{\downarrow}{#2}}}{#1}}
 
\makeatother
\begin{document}
 
\[
	U_x\explain{=}{\textrm{C.-R.}}V_y\explainup{\geq}{V(x,y)=ye^x}0
\]
 
\end{document}

Will result in

TEXMF will be the directory of you local TeX tree (usually /usr/share/texmf). Before Begining the installation process make sure you have the Culmus fonts installed. Apparently Culmus is not optional it’s a requirement. I’ll assume that your Culmus fonts are installed in /usr/share/fonts/culmus.

1. Download the ivritex-1.2.1 source-code from here .
2. Extract the archive into a temporary directory.
3. Save the diff file below a file named “Makefile_patch” and save it inside ivritex-1.2.1/fonts/culmus .
4. Apply the patch by going to the ivritex-1.2.1/fonts/culmus directory (under the directory where you extracted the source archive) and executing “patch Makefile_patch. The patch will alter the places where some file will be installed.
5. As root execute “updmap –enable Map culmus.map”.
6. Still as root execute “mktexlsr”.
7. Ivritex 1.2.1 should be installed now.

--- Makefile	2007-02-14 19:59:52.000000000 +0200
+++ Makefilenew	2007-02-16 10:11:07.000000000 +0200
@@ -20,8 +20,8 @@
 vf_target     = $(TEX_ROOT)/fonts/vf/culmus
 # this is where ivritex will eventually be:
 tex_target    = $(TEX_ROOT)/tex/generic/babel
-encode_dir    = $(TEX_ROOT)/dvips/base
-dvips_cfg_dir = $(TEX_ROOT)/dvips/config
+encode_dir    = $(TEX_ROOT)/fonts/enc/dvips/base
+map_dir       = $(TEX_ROOT)/fonts/map/
 sysconf       = $(DESTDIR)/etc
 updmap_dir    = $(sysconf)/texmf/updmap
 #culmus_target = $(PREFIX)/fonts/culmus
@@ -137,11 +137,11 @@
 	mkdir -p $(sysconf)/texmf/updmap.d
 	echo "Map culmus.map" >$(sysconf)/texmf/updmap.d/10culmus.cfg
 else
-	mkdir -p $(dvips_cfg_dir)
-	cp culmus.map $(dvips_cfg_dir)/
+	mkdir -p $(map_dir)
+	cp culmus.map $(map_dir)/
   ifeq ($(tetex_ver),2)
 	# this should run mktexlsr as well
-	$(updmap) --enable Map $(dvips_cfg_dir)/culmus.map
+	$(updmap) --enable Map $(map_dir)/culmus.map
   else # for tetex-1
     ifeq ($(tetex_ver),1)
 	# TODO: fill in sed line here