# Help:Contents

## Contents

## Organisation of the Explanatoy Supplement

The explanatory supplement is organised in terms of what MediaWiki calls Categories. Using categories provides an automatic mechanism for Index and Table of Contents generation that would otherwise be time consuming and error prone. On top of that, there are a number of extensions based on the category concept, providing a useful set of features for the development, maintenance and use of this Wiki.

Each of the entries in the table of contents in the Main Page is a category. Categories are pages (and for the ES one expects them to be reasonably self contained for the subject they cover). and can independently be added to a [Help:Contents#Collection | Collection] and collections can be printed as pdf books.

## Use of the available extensions

### MathJax

The MathJax extension allows the use of MathJax, a display engine for mathematics providing high quality mathematics fonts. The main interest for the ES lies in its ability to produce high quality display of latex formulae with no need for any extra tags. Equations may simply be written in Latex and MathJax will recognize the Latex Tags.

Simple mathematical expressions can be easily written inline. The following

$x^2 + y^2 +z^2 = 1$

will be displayed by MathJax as $x^2 + y^2 +z^2 = 1$.

We can write complex equations and even make use of \newcommand as illustrated by the following lines.

$ \newcommand{\Re}{\mathrm{Re}\,} \newcommand{\pFq}[5]{{}_{#1}\mathrm{F}_{#2} \left( \genfrac{}{}{0pt}{}{#3}{#4} \bigg| {#5} \right)} $ \begin{align} \label{def:Wns} W_n (s) &:= \int_{[0, 1]^n} \left| \sum_{k = 1}^n \mathrm{e}^{2 \pi \mathrm{i} \, x_k} \right|^s \mathrm{d}\boldsymbol{x} \end{align} \begin{align} \label{eq:W3k} W_3(k) &= \Re \, \pFq32{\frac12, -\frac k2, -\frac k2}{1, 1}{4}. \end{align}

MathJax will display these as $

\newcommand{\Re}{\mathrm{Re}\,} \newcommand{\pFq}[5]{{}_{#1}\mathrm{F}_{#2} \left( \genfrac{}{}{0pt}{}{#3}{#4} \bigg| {#5} \right)}

$ \begin{align}

\label{def:Wns} W_n (s) &:= \int_{[0, 1]^n} \left| \sum_{k = 1}^n \mathrm{e}^{2 \pi \mathrm{i} \, x_k} \right|^s \mathrm{d}\boldsymbol{x}

\end{align}

\begin{align}

\label{eq:W3k} W_3(k) &= \Re \, \pFq32{\frac12, -\frac k2, -\frac k2}{1, 1}{4}.

\end{align}

We can also refer to equations with a valid \label using the latex \eqref command. The second of the two eqautions above can be referred to with

\eqref{eq:W3k}

resulting in a correct reference to equation \eqref{eq:W3k} above. Note the reference works as a link. Clicking it you will be taken to the equation referred to.

### Collection

The Collection extension allows a user to organise a set of pages as a book that can be converted to pdf. This comes handy for a user that is interested in a few sections of the ES but would rather print only the contents of the sections of interested than the entire ES. The user adds each section of interest to a <it>book</it> using a button on the toolbar. When the selection is complete the generate pdf button is pressed and a pdf version of the selected section, including a table of contents, is generated.

This section is still incomplete waiting for the extension to be installed.