Tuesday, March 23, 2010

Nicely formatted listings in LaTeX with adjusted fonts

I'm using the listings package in order to get nicely formatted listings in latex. Since many people are used to the fonts and syntax highlighting of their IDE, I tried to emulate the layout and colors of code as it is formatted in Eclipse. Thanks to XeTeX, I'm able to simply change the font in listing as well. I use two fonts for listing paragraphs and inline:

\newfontfamily\listingsfontinline[Scale=0.8]{Courier New} 
This enables bold fonts in typewriter, another way of solving this problem is to use LuxiMono, but I haven't tried that one. Then I define the colors Eclipse uses, comments are defined a little bit darker:

\definecolor{sh_comment}{rgb}{0.12, 0.38, 0.18 } %adjusted, in Eclipse: {0.25, 0.42, 0.30 } = #3F6A4D
\definecolor{sh_keyword}{rgb}{0.37, 0.08, 0.25}  % #5F1441
\definecolor{sh_string}{rgb}{0.06, 0.10, 0.98} % #101AF9
Sometimes I need math text in listings, e.g. when writing pseudo code. Since I scaled the fonts down, the normal math fonts (displaystyle) are a little bit too large. One possible solution of resizing the math fonts would be to use \DeclareMathSizes, however I do not want to change the font for the whole document. The listings package provides two properties "escapebegin" and "escapeend", which are inserted before and after escaping to latex or math. However, simply using escapebegin={\ \scriptstyle} would cause errors when escaping not to math but to normal latex mode. In order to solve that problem, I define a custom command:

\def\lstsmallmath{\leavevmode\ifmmode \scriptstyle \else  \fi}
\def\lstsmallmathend{\leavevmode\ifmmode  \else  \fi}
Now I'm ready to define the overall style for listings:

\lstset {
 basicstyle= \listingsfont,
 keywordstyle = \color{sh_keyword}\bfseries,
 xleftmargin=0.7cm, xrightmargin=0.5cm,
 escapebegin={\lstsmallmath}, escapeend={\lstsmallmathend}
Comments are printed italic for black-white prints. In order to simplify the use of \lstinline, I define some commands for my favorite languages, e.g.,

\newcommand{\lstJava}[1]{\lstinline[language=Java,breaklines=true,basicstyle= \listingsfontinline]$#1$}


\begin{lstlisting}[language=Java, caption={Just a test}, label={lst:Test}]
package de.jevopi;

 * This is my class
public class Test {

 public void foo(String s) {
  System.out.println("Hello " + s);

will produce the following output (on the left). On the right, you can see the Eclipse version of the very same code snippet. (Click to enlarge images)

Thursday, March 4, 2010

Spell Checker, LaTeX, and OS X

Spell checking is a standard feature today. With LaTeX however it is not too easy to achieve. You can certainly use the build-in spell checker of OS X, but then you have to "proof read" all LaTeX commands and their parameters, which can be annoying. So I was looking for a better solution.

Because it was automatically installed I tried Excalibur. Frankly, I don't like it at all, but maybe I have missed something. It only offers very limited options. Unfortunately it doesn't support UTF-8. Since I'm using XeTeX wiht UTF-8, a spell checker w/o UTF-8 support is useless for me.

So I tried Aspell. If you look at the Aspell webpage, you'll get this "Linux users have to compile their application" feeling. There is a darwin port of aspell triggering a "Darwin users have to compile their application" feeling...

Fortunately, I eventually found CocoAspell. (Yes, well, there's a link to it on the TeXShop website ;-) ...) It comes with an installer, so you don't have to install XCode or Fink :-D. Best of all, it installs a system preference panel -- and that's really great! With this filter shown in the screenshot you can define LaTeX commands and if their arguments are to be spell checked. For example, the argument of \section{} is to be spell checked, while labels (\label{} ) are not to be spell checked. It comes with a list of predefined commands, and I added some commands, e.g., \autoref{} (as you can see in the screenshot).

You can find dictionaries at ftp://ftp.gnu.org/gnu/aspell/dict, before downloading them read the hints at cocoAspell's webpage.

I had some problems activating the Aspell dictionaries in TeXShop. Of course, you have to activate the dictionary in cocoAspell's prefernce panel. And I had to deactivate the "check spelling" box in the TeXShop preference, I don't know why. Spell checking is activated in TeXShops edit menu, I don't know what this preference setting is good for...

Well, spell checking a document for the first time usually means to add a lot of word to the dictionary. Sometimes, you want to edit this user dictionary (maybe because you added a word by mistake of because you want to add an existing list). The user dictionaries can be found at ~/Library/Spelling. These files are simple text files and you can open and edit these files with almost any editor. However, the words are separated with an usually invisible character, so you have to use an editor which can show invisible characters, such as SubEthaEdit (unfortunately, TeXShop cannot show these characters).

OK, now that we have a nice spell checker for LaTeX, we only have to change the language in "Spelling and Grammar". However, opening that tiny window requires a bunch of mouse clicks, and often we do not want to actually spell check but only change the dictionary. I found a small applescript at maxoxhints forum, and the version provided by Eponymous works for me. Eponymous' script could be added to the apple script menu and then will be available in all applications. Note: In order to make this script work, you have to activate "Enable access for assistive devices" in the "Universal Access" panel of the system preferences.

Tuesday, March 2, 2010

Create Section Headers with TexShop and Applescript

I really like the macro feature of TexShop. One of the most common use cases of macros would probably be the definition of a section (or subsection etc.). My section-creation-macro has been quite simple in the past:

% ----------------------------------------
% \section{#SEL##INS#}
% \label{sec:#SEL#}
% ----------------------------------------
This small snippet creates a nicely formatted section header including a label. However, there's a really annoying problem: When creating a reference to a section (that is, to its label), TeXShop does not handle spaces accordingly when selecting a label from the dropdown list. For example, if your label is something like \label{sec:Hello World}, the complete label is shown in the list, but only \ref{sec:Hello} is inserted into the text. In order to overcome this problem, I always replace spaces in labels with underscores. So my label would be "sec:Hello_World", and TeXShop is working perfectly. But replacing spaces with underscores by hand is even more annoying. So I replaced my section macro with an applescript version:

--Applescript direct

-- Create a section header from selected text. A label is automatically added with a prefix
-- "sec:", spaces are converted to underscores.
-- (C) 2010 Jens von Pilgrim

property level : "section"
property cmtchar : "-"
property cmtlength : 78
property labelprefix : "sec:"
-- property newline: "\n"
tell application "TeXShop"
 tell application "TeXShop" to set title to the content of the selection of the front document
 set new_title to title
 if ((count of the paragraphs of title) ≥ 1) then
  set this_line to paragraph 1 of title
  set label to this_line
  set add to "true"
  -- replace commands
  set label to do shell script ¬
   "echo " & the quoted form of label & ¬
   " | sed -E 's/([[:space:]]|[[:punct:]])/_/g'"
  set comment to "% "
  repeat with ii from 1 to cmtlength
   set comment to comment & cmtchar
  end repeat
  set new_title to ¬
   comment & return & ¬
   "\\" & level & "{" & title & "}" & return & ¬
   "\\label{" & labelprefix & label & "}" & return & ¬
   comment & return
 end if
 tell application "TeXShop" to set the selection of the front document to new_title
end tell
This macro creates a section just like the initial macro version, but this time spaces are automatically replaced in the label. That is, simply select your section title, activate the macro, and you get a nicley formatted title with a TeXShop compatible label. E.g. Mark
Hello World, this is great
and the macro will convert this to
% ==============================================================================
\section{Hello World, this is great}
% ==============================================================================
You can easily adjust the macro in order to create subsection, subsubsections or chapters as well. I have different kind of comments for different section levels, all you have to change are the properties in the first line:

property level : "section"
property cmtchar : "-"
property cmtlength : 78
property labelprefix : "sec:"
Change level to "subsection" or whatever, and set the cmtchar to "*", "." or whatever you like. Changing a section level has already been subject of another blog post: Increase/Decrease Section Level with TeXShop Macros.