LaTeX — Practical Notes#

# Ubuntu / WSL: full install, large but easiest
sudo apt update
sudo apt install texlive-full pandoc -y

# Lighter install
sudo apt install texlive-latex-recommended texlive-fonts-recommended texlive-latex-extra pandoc -y

# Check installation
pdflatex --version
pandoc --version

\documentclass[11pt]{article}

\usepackage[a4paper,margin=1in]{geometry}
\usepackage{hyperref}
\usepackage{graphicx}
\usepackage{amsmath,amssymb}

\title{My First LaTeX Report}
\author{Your Name}
\date{\today}

\begin{document}

\maketitle

\section{Introduction}

LaTeX is useful for writing clean PDFs with \textbf{math}, figures, tables, and references.

\section{Math}

Inline math: $E = mc^2$.

Display math:

\[
\sum_{i=1}^{n} i = \frac{n(n+1)}{2}
\]

\section{Link}

Visit \url{https://iitm.ac.in}.

\end{document}

pdflatex hello.tex

# Run twice when using references, table of contents, labels, etc.
pdflatex hello.tex

latexmk -pdf hello.tex

# Clean generated files
latexmk -C

\documentclass{article}

\usepackage{amsmath}     % math
\usepackage{graphicx}    % images
\usepackage{hyperref}    % clickable links

\begin{document}

\title{Title}
\author{Name}
\date{\today}
\maketitle

\tableofcontents

\section{Main heading}
\subsection{Sub heading}

\end{document}

\textbf{bold text}

\textit{italic text}

\texttt{code style}

\emph{important text}

This is a footnote.\footnote{Extra explanation at bottom of page.}

\%   % percent
\&   % ampersand
\$   % dollar
\#   % hash
\_   % underscore
\{ \} % braces

accuracy_score

accuracy\_score

The model predicts $\hat{y}$ from input $x$.

\[
P(y \mid x) = \frac{P(x \mid y)P(y)}{P(x)}
\]

\frac{a}{b}          % fraction

x^2                 % superscript

x_i                 % subscript

\sqrt{x}            % square root

\sum_{i=1}^{n} x_i  % summation

\int_a^b f(x)\,dx   % integral

\alpha \beta \gamma % Greek letters

\leq \geq \neq \approx

\[
A =
\begin{pmatrix}
1 & 2 \\
3 & 4
\end{pmatrix}
\]

project/
├── main.tex
└── figures/
    └── loss.png

\usepackage{graphicx}

\begin{figure}[h]
  \centering
  \includegraphics[width=0.75\linewidth]{figures/loss.png}
  \caption{Training loss over epochs.}
  \label{fig:loss}
\end{figure}

As shown in Figure~\ref{fig:loss}, loss decreases.

\begin{table}[h]
  \centering
  \begin{tabular}{lrr}
    \hline
    Model & Accuracy & F1 \\
    \hline
    BM25 & 0.72 & 0.69 \\
    Dense & 0.81 & 0.78 \\
    Hybrid & \textbf{0.86} & \textbf{0.84} \\
    \hline
  \end{tabular}
  \caption{Retrieval results.}
  \label{tab:results}
\end{table}

l = left
c = center
r = right

\usepackage{booktabs}

\begin{tabular}{lrr}
\toprule
Model & Accuracy & F1 \\
\midrule
BM25 & 0.72 & 0.69 \\
Dense & 0.81 & 0.78 \\
Hybrid & 0.86 & 0.84 \\
\bottomrule
\end{tabular}

@article{vaswani2017attention,
  title={Attention Is All You Need},
  author={Vaswani, Ashish and others},
  journal={NeurIPS},
  year={2017}
}

Transformers were introduced by \cite{vaswani2017attention}.

\bibliographystyle{plain}
\bibliography{references}

pdflatex main.tex
bibtex main
pdflatex main.tex
pdflatex main.tex

latexmk -pdf main.tex

---
title: "TDS Report"
author: "Your Name"
date: today
---

# Introduction

This report was written in Markdown and converted to PDF.

## Equation

The sum is:

$$
\sum_{i=1}^{n} i = \frac{n(n+1)}{2}
$$

pandoc report.md -o report.pdf

# Better Unicode/font support
pandoc report.md -o report.pdf --pdf-engine=xelatex

# With useful report options
pandoc report.md -o report.pdf \
  --pdf-engine=xelatex \
  --toc \
  --number-sections \
  -V geometry:margin=1in \
  -V fontsize=11pt \
  -V colorlinks=true

latex-report/
├── main.tex
├── references.bib
├── figures/
│   └── architecture.png
├── sections/
│   ├── intro.tex
│   ├── method.tex
│   └── results.tex
└── Makefile

\documentclass{article}

\usepackage[a4paper,margin=1in]{geometry}
\usepackage{graphicx}
\usepackage{amsmath}
\usepackage{hyperref}

\title{Project Report}
\author{Your Name}
\date{\today}

\begin{document}

\maketitle
\tableofcontents

\input{sections/intro}
\input{sections/method}
\input{sections/results}

\bibliographystyle{plain}
\bibliography{references}

\end{document}

main.pdf: main.tex sections/*.tex references.bib
	latexmk -pdf main.tex

clean:
	latexmk -C

make
make clean

Mistake: forgetting to escape _ % & #
Fix: use \_ \% \& \#

Mistake: image not found
Fix: check folder path and file extension

Mistake: citations show [?]
Fix: run latexmk -pdf or compile BibTeX sequence

Mistake: table/figure appears somewhere else
Fix: LaTeX floats figures/tables; use labels and references, not “below image”

Mistake: writing everything in LaTeX when Markdown is enough
Fix: use Markdown for notes, LaTeX for serious PDFs/math-heavy documents

Mistake: package missing
Fix: install missing TeX package or use texlive-full if disk space is okay

mkdir latex-small-demo
cd latex-small-demo

cat > main.tex <<'TEX'
\documentclass[11pt]{article}

\usepackage[a4paper,margin=1in]{geometry}
\usepackage{amsmath}
\usepackage{hyperref}
\usepackage{booktabs}

\title{Small LaTeX Demo}
\author{Your Name}
\date{\today}

\begin{document}

\maketitle

\section{Goal}

This PDF shows text, math, table, and link usage.

\section{Math}

The average of $n$ values is:

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

\section{Result Table}

\begin{table}[h]
\centering
\begin{tabular}{lr}
\toprule
Method & Score \\
\midrule
Baseline & 72 \\
Improved & \textbf{86} \\
\bottomrule
\end{tabular}
\caption{Simple experiment result.}
\end{table}

\section{Link}

Course website: \url{https://tds.s-anand.net}

\end{document}
TEX

latexmk -pdf main.tex

[ ] I know LaTeX is best for math-heavy PDF reports.
[ ] I can create a .tex file and compile it.
[ ] I know inline math uses $...$.
[ ] I know display math uses \[...\].
[ ] I can add sections, tables, images, and citations.
[ ] I know special characters like _ and % need escaping.
[ ] I know latexmk is easier than manual multiple compiles.
[ ] I can use Pandoc to convert Markdown to PDF.
[ ] I use Markdown for simple notes and LaTeX for polished reports.