LaTeX

Scientific Computing

Prof. Calvin

Why LaTeX?

What is LaTeX?

• A document preparation system that produces high-quality typesetting.
• Ideal for complex documents, especially in scientific and academic fields.
• Provides precise control over layout, formatting, and mathematical expressions.

Different Flavors of LaTeX

• LaTeX is built on TeX, a typesetting engine.
• Distributions like TeX Live (for Linux/Unix/Windows) and MiKTeX (for Windows) bundle everything you need.
• Online editors like Overleaf simplify collaboration and compilation.

Where is LaTeX Used?

• Primarily in academia for theses, dissertations, journal articles, and presentations.
• Widely adopted in mathematics, physics, computer science, and engineering.
• Excellent for consistent, professional-looking documents.

Conceptualizing

• Imagine writing a research paper about a statistical model:
  • You’d want to include complex equations, figures, and tables.
  • You’d need precise control over citations and bibliographies.
  • LaTeX handles these intricate elements beautifully.

Problem Solving

• LaTeX:
  • Separates content from formatting, allowing you to focus on writing.
  • Automates cross-referencing, numbering, and table of contents generation.
  • Produces consistent, high-quality output every time.
• Can be:
  • Written in any text editor.
  • Authored in a dedicated LaTeX editor with live preview.

Stepping Back

• For professional, polished documents, especially with a lot of math or figures, LaTeX is the gold standard.
• While Markdown is great for quick documentation, LaTeX offers unparalleled power and flexibility for formal publications.

We will

• Introduce basic LaTeX syntax:
  • Structure documents
  • Style text and equations
  • Include figures and tables
• Use LaTeX to:
  • Create a simple academic document

Publishing

• LaTeX files usually end with a .tex extension.
• Compiling a .tex file generates a PDF document.
• It’s a powerful tool for creating professional, structured documents.

Essentials

A note

• These slides are written in Markdown, but we’ll show LaTeX source on the left and a conceptual rendering on the right.
• You can try compiling LaTeX online at sites like Overleaf.

Getting stated

• \begin{document} and `\end{document}```- These commands mark the beginning and end of your document’s content.
• Everything you want to appear in your final PDF goes between these two commands.
• Anything before \begin{document} is called the preamble, where you set up document-wide settings.

\documentclass{article}

\begin{document}
Hello, LaTeX world!
\end{document}

\[ \text{Hello, LaTeX world!} \]

Titles, Authors, and Dates

• You can easily add a title, author, and date to your document.
• Use \maketitle in the document environment to display this information.
• No graceful way to display this…

\documentclass{article}
\title{My Awesome Document}
\author{Your Name}
\date{June 2025}

\begin{document}
\maketitle
\end{document}

Packages

• Packages extend LaTeX’s functionality, allowing you to do more complex things.
• You declare packages in the preamble using \usepackage{packagename}.
• For example, graphicx lets you include images, and amsmath provides advanced math features.
• No graceful way to display this…

\documentclass{article}
\usepackage{graphicx} % For images

\begin{document}
We could include an image like so.

\includegraphics{julia.png}
\end{document}

Text

Bold

• Use \textbf{} or {\bfseries} to make text bold.

We can make text \textbf{bold}.

\(\text{We can make text \textbf{bold}.}\)

Italic

• Use \textit{} or {\itshape} to italicize text.

We can make text \textit{italic}.

\(\text{We can make text \textit{italic}.}\)

Underline

• Use \underline{} to underline text.

We can \underline{underline} text.

\(\text{We can } \underline{\text{underline}} \text{ text.}\)

Sub/Superscript

• In scientific publication, we often require subscripts and superscripts.
• We enter “math mode” with $ and use ^ or _
• To style text normally in math mode, use \text{}

Squaring $x$ as $x^2$

Denoting a Helium-3 isotope as $\text{He}_3$

\(\text{Squaring } x \text{ as } x^2\)

\(\text{Denoting a Helium-3 isotope as He}_3\)

Special Characters

• Many characters have special meaning in LaTeX and need to be escaped.
• % for comments and & for table alignment.

The percent sign is \%.
An ampersand is \&.

\(\text{The percent sign is \%.}\) \(\text{An ampersand is \&.}\)

Equations

Inline Math

• Use $ delimiters for inline mathematical expressions.

$E=mc^2$

\(E=mc^2\)

Displayed Math

• Use $$ delimiters or \[ \] for standalone, centered equations.

$$
E=mc^2
$$

\[ \sum_{i=1}^n x_i \]

\[E=mc^2 \]

\[ \sum_{i=1}^n x_i \]

Numbered Equations

• Use the equation environment to automatically number equations.
• (Doesn’t work on these slides!)

\begin{equation}
    a^2 + b^2 = c^2
\end{equation}

\[\begin{equation} a^2 + b^2 = c^2 \end{equation}\]

Multiple Equations

• Use the align environment for multiple aligned equations.
• This is where & matters!

\begin{align}
    2x + 3y &= 7 \\
    x - y &= 1
\end{align}

\[\begin{align} 2x + 3y &= 7 \\ x - y &= 1 \end{align}\]

Lists

Unordered Lists

• Use the itemize environment for bulleted lists.

\begin{itemize}
    \item First item.
    \item Second item.
\end{itemize}

Ordered Lists

• Use the enumerate environment for numbered lists.

\begin{enumerate}
    \item Step one.
    \item Step two.
\end{enumerate}

Nested Lists

• Lists can be nested by placing one list environment inside another.

\begin{itemize}
    \item Main point.
    \begin{enumerate}
        \item Sub-point A.
        \item Sub-point B.
    \end{enumerate}
\end{itemize}

Sections

Document Structure

• LaTeX uses commands like \section, \subsection, etc., to structure your document.
• These are the same intent as # and ##.

\section{Introduction}
\subsection{Background}

Automatic Numbering

• Sections, figures, and tables are automatically numbered.

\section{Results}
See Section~\ref{sec:methods} for details.
\section{Methods} \label{sec:methods}

Tables

Basic Tables

• Use the tabular environment to create tables.
• | creates vertical lines, h for horizontal lines, l, c, r for column alignment.

\begin{tabular}{|l|c|r|}
\hline
Left & Center & Right \\
\hline
Data 1 & 2.5 & 100 \\
Data 2 & 3.0 & 200 \\
\hline
\end{tabular}

Table Caption

• Use the table environment with \caption to add a caption and label.

\begin{table}[h!]
\centering
\caption{A simple table}
\label{tab:simple}
\begin{tabular}{|l|l|}
\hline
Header A & Header B \\
\hline
Row 1A & Row 1B \\
\hline
\end{tabular}
\end{table}

Images

Including Images

• Use the graphicx package and \includegraphics to add images.

\usepackage{graphicx} % in preamble
\includegraphics[width=0.8\textwidth]{julia.png}

Figure Environment

• Use the figure environment with \caption and \label for proper referencing.

\begin{figure}[h!]
\centering
\includegraphics[width=0.8\textwidth]{julia.png}
\caption{The Julia set.}
\label{fig:julia}
\end{figure}

References

Basic Citations

• LaTeX has robust citation management with BibTeX or BibLaTeX.
• This is programmable, and can look whoever you like, for example:

...as shown by Smith \cite{smith2020}.

\begin{thebibliography}{9}
\bibitem{smith2020}
J. Smith, \textit{A Great Book}, Publisher, 2020.
\end{thebibliography}

…as shown by Smith [1].

References [1] J. Smith, A Great Book, Publisher, 2020.

Cross-referencing

• Refer to figures, tables, and sections using \ref{}.

As seen in Figure~\ref{fig:example} and Table~\ref{tab:simple}.

As seen in Figure 1 and Table 1.

Exercise

Exercise

• Complete the “Learn LaTeX in 30 minutes” tutorial.
• Download the PDF.
• Add the PDF to your scientific computing repostitory as “30_min.pdf”