LPD L^ATEX Tutorial

Felix Gärtner

3 June 2003

Remark: This file was produced from the original LaTeX slides using latex2html to make some portions of text available for copy and paste. The typographical finesses can only be viewed on the original pdf file, which is available at http://lpdwww.epfl.ch/fgaertner/latex/latex-tutorial.pdf

Goals

Some basics of typography and TEX operation
Logical vs. visual markup
Beautiful graphics with xfig and Metapost
Producing pdf

This material is available at http://lpdwww.epfl.ch/fgaertner/latex

Book Printing vs. Ordinary Typing [Knu90, Ch. 2]

Adjustments, when moving from typewriter to a computer terminal (e.g., difference between digit `1' and lowercase letter `l').
More adjustments when moving from computer terminal to book publishing:
Keyboard has undirected quote mark ("), typographic quote marks are directed:
```
     ``I understand.''
```
yields: ``I understand.''

Four forms of hyphens:
- normal hyphen (-) for compound words like `daughter-in-law'.
- en-dash (-) for number ranges like `pages 1-3'.
- em-dash (--) for punctuation in sentences--sometimes these ones are simply called dashes.
- minus sign ( ) in math formulas.
Try and distinguish these hyphens:
- for a hyphen, type a single hyphen `-'
- for an en-dash, type two hyphens `--'
- for an em-dash, type three hyphens `---'
- for a minus sign, type a hyphen in math mode ` $-$ '

Controlling TEX [Knu90, Ch. 3]

Keyboard is too limited to be able to encode all typographic commands directly.
Escape character let's you switch to ``instruction mode'' of TEX.
In TEX, escape character is the backslash `\'
Typesetting instruction: `\<typesetting command>'
Example: `\TeX' means `typeset the TEX logo'
Example: `\"' means `put accent over following character'
First type is a control sequence, second type is a control symbol.
Control symbols: backslash plus one additional character.

- Examples: accents `\'' or `\`'
Control sequences: backslash plus sequence of letters A..Z and a..z
- Control sequence ends at first non-letter character. If this character is a space, it is eaten up.
  \TeX ignores spaces after control words.
  
  gives: TEXignores spaces after control words.
- But: `the logo `\TeX''
- If you need a space, write `\TeX\ is good'
- Non-breakable space: `\TeX~is good'

Grouping [Knu90, Ch. 5]

Special characters `{' and `}' can be used for grouping, similar to a scope.
Commands and definitions inside the group do not affect definitions outside of the group.
Example font switching: `{\large larger text} and smaller' instead of `\large larger text \normalsize and smaller'
Also holds for type changing (bold, italics, etc.).
Empty group can be used to end control sequences: `\TeX{}'
Remark: we're silently switching from TEX to L^ATEX now; L^ATEX is just a macro package using plain TEX commands (size switching commands are only in L^ATEX).

Grouping also used for defining the reach of control sequences.
Example: \textit{This is italics.}
If a control sequence needs an argument, it either takes the next letter, control sequence or the next group.
- `\textit{This is \textbf{bold}.}'
- `\textit\TeX{}'
- But: `\textit This is italics'
- and: `\textitThis is italics'
Same rules: use of grouping in math mode.

How TEX reads what you type [Knu90, Ch. 7]

This is for people who use a text editor (like emacs) for editing manuscripts.
Rules:
- A <return> is like a space.
- Two spaces in a row count as one space.
- A blank line denotes the end of a paragraph.
A comment character `%' escapes the return (like a backslash in many programming tools).
You can use spacing to structure your file (example follows).



You can insert linebreaks at any point in a paragraph without
ending it. If you need a paragraph, insert one (or more) blank
lines.

You can use the rules to structure the input text. If you have
a displayed math formula, you can write
  %
$$x + y = z$$
  %
to visually separate it in the input file. If necessary, you
can also avoid spaces at the end of line like in th%
is example.  You can also indent text to follow grouping:

\begin{center}
  \begin{large}
    This is the major title
  \end{large}

  and this the subtitle
\end{center}

And you can use empty lines to visually separate items in
lists:
  %
\begin{itemize}

\item Empty lines before and after items are ignored

\item So it looks much better in the input file. You can
  use indentation here too.

\end{itemize}
  %
You can visually separate the following lines without inserting
a paragraph.

Like the backslash, there are other special characters which don't mean what they look like:
- Beginning and ending of group: `{' and `}'
- Toggle math mode: `$'
- Alignment and parameter: `&' and `#'
- Superscript and subscript: `^' and `_'
- Comment character: `%'
All these characters have to be escaped to be printed, e.g., `\&' for `&'

Logical Markup vs. Visual Markup

Markup are the control sequences within text (HTML is another markup language).
Visual markup directly refers to the appearance: `\textit{emphasized}'
Logical markup refers to logical role of text, indirectly refers to appearance: `\emph{emphasized}'
Logical markup separates contents from layout; L^ATEX was written to promote logical markup.
FCG's most often stated rule in using L^ATEX: Always use logical markup instead of visual!

Example:
Consensus is defined using two primitive operations propose and decide. If a process invokes we say that it proposed .

Maybe written as:

    Consensus is defined using two primitive operations 
    \textit{propose} and \textit{decide}. If a process 
    invokes $propose(v)$ we say that it proposed $v$.

Gives:
Consensus is defined using two primitive operations propose and decide. If a process invokes we say that it proposed .

Two objections:
- ` $propose$ ' is the product of , , ... not the identifier `propose' (awfull spacing). Look for example at ` ' vs. `definitely'.
- What if you decide to change from italics to slanted?

The primitives propose and decide should be marked up (logically) as ``primitives'', not as italicized words.

    Consensus is defined using two primitive 
    operations \primitive{propose} and 
    \primitive{decide}. If a process invokes 
    $\primitive{propose}(v)$ we say that it 
    proposed $v$.

Defining your own Logical Markup

Use the L^ATEX facilities to define own commands:

    \documentclass{article}
    ...
    \newcommand{\primitive}[1]{\textit{#1}}
    ...
    \begin{document}
    ...

Invoking `\primitive{x}' is now a macro substitution. Note separation of logical and visual roles of the text.
Small set of well-chosen logical macros sufficient.

Popular Logical Markup for LPD

    \usepackage{latexsym}% for \Diamond
    \newcommand{\eventually}{\Diamond}
    \newcommand{\textcal}[1]{{\cal #1}}
    \newcommand{\perfect}{\textcal{P}}

Now you can write:

    Solving consensus is possible using $\eventually\perfect$.

yields:

Solving consensus is possible using .

Creating Graphics with `xfig`

Who has used xfig? Powerful program for creating complex figures.
Short demonstration.
Possible to include TEX text in figure and use L^ATEX fonts.
To make this available in your L^ATEX file, export in Metapost format.
File `graph.mp' has to be ``compiled'' using Metapost mpost giving a ``eps-ish'' type of file `graph.0'.

Including Metapost Figures

File can now be included in L^ATEX document:

    \documentclass{article}
    \usepackage[dvips]{graphicx}% note the `cx'
    ...
    \begin{document}
    ...
    \begin{center}% figure can be scaled etc.
      \includegraphics[scale=0.7]{graph.0}
    \end{center}
    ...

Example Figure

Going PDF

Instead of invoking latex you can simply invoke pdflatex (it's that simple).

You will directly get pdf output (without having to convert Postscript to pdf).

Works seamlessly with Metapost if you load graphicx like this:

    % to make Metapost figures useable in pdflatex 
    % and normal latex (include as `file.0')
    \ifx\pdftexversion\undefined
      \usepackage[dvips]{graphicx}
    \else
      \usepackage[pdftex]{graphicx}
      \DeclareGraphicsRule{*}{mps}{*}{}
    \fi

Does not work with eps files and epsfig package.
Switch to graphicx package (epsfig is outdated anyway).
- Using normal latex you can replace calls of `\epsfig' with calls to `\includegraphics'
Leave away extension, then `\includegraphics' will choose the ``right'' file.
- pdflatex can't handle eps file, but eps files can be converted to pdf using epstopdf.
- If you have graph.eps and graph.pdf, then `\includegraphics{graph}' will automatically choose the right file depending whether you invoke latex or pdflatex.

Other Useful Things

cite: handle bibliographic labels nicely (sort them, etc.)
See the ``L^ATEX Companion'' [GMS93] for more.
For general rules on language, wording, abbreviations, typesetting etc. see the ``Chicago Manual of Style'' [Chi93]
Indispensable AucTEX mode for emacs: http://www.gnu.org/software/auctex/
See also: Knuth's booklet on ``Mathematical Writing'' http://www-cs-faculty.stanford.edu/~knuth/klr.html

Bibliography

Chi93: The Chicago Manual of Style.
The University of Chicago Press, forteenth edition, 1993.
GMS93: Michael Goossens, Frank Mittelbach, and Alexander Samarin.
The L^ATEX Companion.
Addison-Wesley, Reading, MA, Reading, MA, USA, 1993.
Knu90: Donald E. Knuth.
The TEXbook.
Addison-Wesley, Reading, MA, 1990.

About this document ...

This document was generated using the LaTeX2HTML translator Version 2002 (1.62)

The command line arguments were:
latex2html -split 0 -nonavigation latex

The translation was initiated by on 2003-06-03

2003-06-03