Technical Report Writing with LaTeX

Before we start

Why this matters

Outline · Labs II–III

Topics in this chapter

Select a topic to jump to the slide that explains it.

1. Getting started
2. Errors
3. Mathematics
4. Packages
5. Structured documents
6. Figures, tables and code
7. Citations
8. The technical report

Concept 1 of 23

What LaTeX is

LaTeX (pronounced “lay-tek” or “lah-tek”) is a document preparation system used worldwide for scientific papers, theses, books and slides. You write plain text with commands; a compiler turns it into a beautifully typeset PDF.

• It separates content from style: change the document class or a package and the whole layout changes.
• It numbers sections, figures, tables and equations automatically and keeps every cross-reference right.
• It builds the table of contents and bibliography for you.
• Journals and conferences (IEEE, ACM, Springer) publish LaTeX templates: you add only the content.

Concept 1 of 23

What LaTeX is (cont.)

Getting started

Your first document

\documentclass{article}
\begin{document}
Hello World! % your content goes here...
\end{document}

Interactive

Try it: typesetting text

Interactive

Try it: typesetting text (cont.)

Words are separated by one or more spaces; paragraphs by one or more blank lines. Extra spaces in the source are collapsed in the output.

Typesetting text

Special characters

Ten characters have special meanings. Typing them directly causes an error or a surprise.

Quotes: use `` and '' for “double” and ` ' for ‘single’ quotes.

Typesetting text

Special characters (cont.)

Typesetting text

Handling errors

Exercise

Exercise 1: find and fix the errors

Exercise

Exercise 1: find and fix the errors (cont.)

\documentclass{article}
\begin{document}
In March 2006, Congress raised that ceiling an additional \$0.79
trillion to \$8.97 trillion, which is approximately 68\% of GDP. As of
October 4, 2008, the ``Emergency Economic Stabilization Act of
2008'' raised the current debt ceiling to \$11.3 trillion.
\end{document}

Concept 7 of 23

Mathematics: inline and displayed

• Dollar signs mark maths in the text: $c = a - b + 1$. Always use them in pairs.
• LaTeX handles spacing in maths itself — it ignores your spaces.
• Big formulas go on their own line in an equation environment, which is numbered; equation* (from amsmath) is unnumbered.
• Do not leave blank lines inside maths.

Concept 7 of 23

Mathematics: inline and displayed (cont.)

The roots of a quadratic equation are given by
\begin{equation}
x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}
\end{equation}
where $a$, $b$ and $c$ are \ldots

Mathematics

amsmath: operators and aligned equations

\usepackage{amsmath}   % in the preamble

\begin{equation*}
\min_{x,y} (1-x)^2 + 100(y-x^2)^2
\end{equation*}

\begin{equation*}
\beta_i = \frac{\operatorname{Cov}(R_i, R_m)}{\operatorname{Var}(R_m)}
\end{equation*}

\begin{align*}
(x+1)^3 &= (x+1)(x+1)(x+1) \\
        &= (x+1)(x^2 + 2x + 1) \\
        &= x^3 + 3x^2 + 3x + 1
\end{align*}

Mathematics

amsmath: operators and aligned equations (cont.)

• LaTeX reads adjacent letters as variables multiplied together, so min would print in italics. amsmath defines upright operators such as \min, \max, \log.
• \operatorname{Cov} makes your own operator.
• In align*, & marks the alignment point (before the =) and \\ starts a new line.
• align without the star numbers every line; add \nonumber to skip one.

Interactive

Try it: maths

Interactive

Try it: maths (cont.)

Change a formula and watch the page. Try deleting a $ or the \usepackage{amsmath} line to see the errors LaTeX gives.

Exercise

Exercise 2: typeset the central limit theorem

Exercise

Exercise 2: typeset the central limit theorem (cont.)

\documentclass{article}
\usepackage{amsmath}
\begin{document}
Let $X_1, X_2, \ldots, X_n$ be a sequence of independent and identically
distributed random variables with $\operatorname{E}[X_i] = \mu$ and
$\operatorname{Var}[X_i] = \sigma^2 < \infty$, and let
\begin{equation*}
S_n = \frac{1}{n}\sum_{i=1}^{n} X_i
\end{equation*}
denote their mean. Then as $n$ approaches infinity, the random variables
$\sqrt{n}(S_n - \mu)$ converge in distribution to a normal $N(0, \sigma^2)$.
\end{document}

Structure

Environments and lists

\begin{itemize}   % bullet points
  \item Biscuits
  \item Tea
\end{itemize}

\begin{enumerate}  % numbers
  \item Biscuits
  \item Tea
    \begin{itemize}
      \item green      % lists can nest
    \end{itemize}
\end{enumerate}

\begin{description}
  \item[SRS] Software Requirements Specification
\end{description}

Structure

Environments and lists (cont.)

• \begin{name} … \end{name} creates an environment: a context that changes how its content is typeset.
• itemize gives bullets, enumerate numbers, description bold labels.
• Every \begin needs a matching \end, closed in reverse order.
• You could even write $…$ as \begin{math}…\end{math}.

Concept 12 of 23

Packages

All the commands so far are built into LaTeX. Packages are libraries of extra commands; load each one with \usepackage in the preamble.

Concept 12 of 23

Packages (cont.)

\documentclass{article}
\usepackage{amsmath}   % preamble
\begin{document}
% now we can use commands from amsmath here...
\begin{align*}
a^2 + b^2 &= c^2 \\
\max(a, b) &\leq c
\end{align*}
\end{document}

Concept 13 of 23

Title, abstract and sections

\documentclass{article}
\title{The Title}
\author{A. Author}
\date{\today}
\begin{document}
\maketitle
\begin{abstract}
Abstract goes here...
\end{abstract}
\tableofcontents

Concept 13 of 23

Title, abstract and sections (cont.)

\section{Introduction}
The problem of \ldots
\section{Method}
We investigate \ldots
\subsection{Sample Preparation}
\subsection{Data Collection}
\section{Results}
\section{Conclusion}
\end{document}

Concept 13 of 23

Title, abstract and sections (cont.)

Concept 13 of 23

Title, abstract and sections (cont.)

Every heading is numbered for you, and the contents list is built from them (after the second compile).

• Tell LaTeX the \title, \author and \date in the preamble; \maketitle prints them.
• The abstract environment makes an abstract.
• \section, \subsection, \subsubsection are numbered automatically (1, 1.1, 1.1.1).
• \section* gives an unnumbered heading that is left out of the table of contents.
• In the report class, \chapter sits above \section.
• \tableofcontents needs two compiles to fill in.

Structured documents

Labels and cross-references

\usepackage{amsmath}   % for \eqref
...
\section{Introduction}
\label{sec:intro}
In Section~\ref{sec:method}, we \ldots

\section{Method}
\label{sec:method}
\begin{equation}
\label{eq:euler}
e^{i\pi} + 1 = 0
\end{equation}
By \eqref{eq:euler}, we have \ldots

Structured documents

Labels and cross-references (cont.)

• Put \label{key} right after the thing you number (section, equation, caption).
• Refer to it with \ref{key}; \eqref{key} adds brackets for equations.
• Never type numbers yourself: if you add a section, every reference updates.
• Use prefixes so keys are readable: sec:, fig:, tab:, eq:.
• Write Section~\ref{…}: the ~ stops the line breaking between the word and the number.
• LaTeX needs two runs: the first records labels, the second prints them. Until then you see ??.

Interactive

Try it: a small report

Interactive

Try it: a small report (cont.)

Change the order of the sections and watch the numbers and the reference update. Delete a \label to see “??” and the warning.

Concept 16 of 23

Figures and floats

\usepackage{graphicx}   % preamble
...
Figure~\ref{fig:model} shows \ldots

\begin{figure}[htbp]
  \centering
  \includegraphics[width=0.5\textwidth]{model}
  \caption{The iterative model.}
  \label{fig:model}
\end{figure}

Concept 16 of 23

Figures and floats (cont.)

• \includegraphics (from graphicx) inserts JPEG, PNG or PDF images. Options: width=0.5\textwidth (half the text width), angle=270, scale=0.8.
• Wrapping it in figure makes a float: LaTeX decides where it fits best.
• Placement hints: h here, t top, b bottom, p own page; [H] (package float) forces “exactly here”.
• \label must come after \caption, or the reference points to the section instead.
• Tables go in a table float, usually with the caption above.

Figures, tables and code

Subfigures

Load caption and subcaption, then place several subfigure environments inside one figure. \hfill spreads them across the line.

\begin{figure}
  \centering
  \begin{subfigure}[b]{0.3\textwidth}
    \centering
    \includegraphics[width=\textwidth]{graph1}
    \caption{$y=x$}
    \label{fig:y equals x}
  \end{subfigure}
  \hfill
  \begin{subfigure}[b]{0.3\textwidth}
    \centering
    \includegraphics[width=\textwidth]{graph2}
    \caption{$y=3\sin x$}

Figures, tables and code

Subfigures (cont.)

    \label{fig:three sin x}
  \end{subfigure}
  \caption{Three simple graphs}
  \label{fig:three graphs}
\end{figure}

Each subfigure gets its own letter, (a) and (b), under one shared figure number.

Figures, tables and code

Tables

\begin{tabular}{|l|r|r|} \hline
Item   & Qty & Unit \$ \\ \hline
Widget & 1   & 199.99  \\
Gadget & 2   & 399.99  \\
Cable  & 3   & 19.99   \\ \hline
\end{tabular}

• The argument gives the column alignment: left, centre, right; p{3cm} wraps text.
• | draws vertical lines; \hline draws a horizontal line.
• & separates columns and \\ ends a row — like align*.
• For reports, the booktabs style (\toprule, \midrule, \bottomrule, no vertical lines) looks more professional.

Figures, tables and code

Tables (cont.)

Figures, tables and code

Algorithms and code listings

\usepackage{algorithm}
\usepackage{algpseudocode}
...
\begin{algorithm}
\caption{Withdraw cash}
\begin{algorithmic}[1]   % [1] = number every line
\State $i \gets 10$
\If{$i \geq 5$}
    \State $i \gets i - 1$
\Else
    \If{$i \leq 3$}
        \State $i \gets i + 2$
    \EndIf

Figures, tables and code

Algorithms and code listings (cont.)

\EndIf
\end{algorithmic}
\end{algorithm}

Figures, tables and code

Algorithms and code listings (cont.)

\If, \Else and \EndIf print the bold keywords and indent the lines for you.

Command names are title-cased: \State, \While, \EndWhile, \For, \Return. The algorithm float adds a caption and number. For real source code, use the listings package instead:

\usepackage{listings}
\begin{lstlisting}[language=Python]
def incmatrix(genl1, genl2):
    m = len(genl1)
    ...
\end{lstlisting}

Interactive

Try it: figures, tables and algorithms

Interactive

Try it: figures, tables and algorithms (cont.)

Swap the two subfigures, add a row to the table or a \State to the algorithm, and watch the numbers and layout follow.

Concept 21 of 23

Citations with BibTeX and biblatex

1. Create a reference file with the .bib extension (Overleaf: New file → citation.bib).
2. Find the paper, journal or book in Google Scholar.
3. Click Cite → BibTeX to get the entry.
4. Paste the entry into the .bib file.
5. In the preamble: \usepackage{biblatex} and \addbibresource{citation.bib}.
6. In the text: \cite{key}; where the list should go: \printbibliography.
7. Compile (Overleaf runs biber and LaTeX again for you).

Concept 21 of 23

Citations with BibTeX and biblatex (cont.)

@article{guyot2002high,
  title={High solid content latexes},
  author={Guyot, A and Chu, F and Schneider, M and Graillat, C and McKenna, TF},
  journal={Progress in Polymer Science},
  volume={27}, number={8}, pages={1573--1615},
  year={2002}, publisher={Elsevier}
}

Concept 21 of 23

Citations with BibTeX and biblatex (cont.)

Concept 21 of 23

Citations with BibTeX and biblatex (cont.)

Interactive

Build a BibTeX entry

Concept 23 of 23

Writing the technical report

Worked example 1 of 3

Worked example 1

The profit was 25\% higher \& the cost fell by \$2,000
(see Table~\ref{tab:cost}).

Worked example 2 of 3

Worked example 2

\begin{equation}
x = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a}
\label{eq:quadratic}
\end{equation}
Equation~\eqref{eq:quadratic} gives both roots.

Worked example 3 of 3

Worked example 3

Practice

Practice (1 of 2)

Try each one on paper first, then check your answer.

\begin{tabular}{lcr}
\hline
Name & Qty & Price \\
\hline
Pen & 2 & 20 \\
\end{tabular}

Practice

Practice (2 of 2)

Try each one on paper first, then check your answer.

\begin{equation*}
S_n = \frac{1}{n}\sum_{i=1}^{n} X_i
\end{equation*}

Check yourself

Quiz

Resources

Further learning

Hand-picked material to go deeper. Links open in a new tab.

Resources

Further learning (cont.)

Summary

Summary

• LaTeX separates content from style and numbers everything automatically; Overleaf compiles it online.
• Escape the special characters # $ % & _ { } ~ ^ \; fix the first error first.
• Maths goes in $…$ inline or equation/equation*/align* on its own line (amsmath).
• Load extra features with \usepackage in the preamble.
• Structure with \section; refer with \label + \ref/\eqref — never type numbers.
• Figures and tables are floats with \caption then \label; tables use & and \\.
• Cite with BibTeX: .bib file, \addbibresource, \cite, \printbibliography.