LaTeX and Technical Documents

LaTeX is a typesetting system that turns plain-text source into beautifully formatted documents, and it is the de facto standard for anything math-heavy. If you write equations, you will get cleaner, more consistent results with LaTeX than with a word processor, and the same math syntax works inside R Markdown, Quarto, and Jupyter.

Why LaTeX for Math?

Equations render precisely and consistently, no fighting an equation editor.
The source is plain text, so it version-controls and diffs cleanly.
The same math notation is portable across papers, slides, notebooks, and websites (via KaTeX/MathJax).

Inline vs. Display Math

Wrap math in dollar signs. A single $...$ is inline (flows within a sentence); double $...$ is display (centered on its own line).

The estimator  $\hat{\beta}$  is unbiased when the errors have mean zero.

 $\hat{\beta} = (X^\top X)^{-1} X^\top y$

Do use inline math for symbols mentioned in prose. Don’t put large multi-line equations inline, they crowd the text; use display math.

Common Constructs

Source	Meaning
`\frac{a}{b}`	fraction $\frac{a}{b}$
`\sum_{i=1}^{n} x_i`	sum from 1 to n
`\alpha, \beta, \gamma, \mu, \sigma`	Greek letters
`x_i` / `x^2`	subscript / superscript
`X \sim N(\mu, \sigma^2)`	“distributed as” ( $\sim$ )
`\bar{x}`, `\hat{\theta}`	bar and hat accents
`\begin{bmatrix} a & b \\ c & d \end{bmatrix}`	a matrix

An example combining several of these:

 $\bar{x} = \frac{1}{n} \sum_{i=1}^{n} x_i, \qquad X_i \sim N(\mu, \sigma^2)$

A Tiny Compilable Document

A complete, minimal .tex file you can compile to PDF:

\documentclass{article}
\begin{document}

The sample mean is  $\bar{x} = \frac{1}{n}\sum_{i=1}^{n} x_i$ .

\begin{equation}
\hat{\sigma}^2 = \frac{1}{n-1}\sum_{i=1}^{n}(x_i - \bar{x})^2
\end{equation}

\end{document}

Using LaTeX from R

You do not need a system-wide LaTeX install. The tinytex R package installs a lightweight, self-contained distribution:

install.packages("tinytex")
tinytex::install_tinytex()   # one-time: sets up LaTeX for PDF rendering

With that in place, R Markdown and Quarto can render PDFs. Math goes directly in the document using the same $...$ syntax:

---
title: "My Analysis"
output: pdf_document      # R Markdown; use `format: pdf` for Quarto
---

The mean is  $\bar{x} = \frac{1}{n}\sum_{i=1}^{n} x_i$ , and we assume
 $X_i \sim N(\mu, \sigma^2)$ .

```{r}
mean(c(1, 2, 3, 4))
```

Render from the R console or the command line:

Rscript -e 'rmarkdown::render("analysis.Rmd")'
quarto render analysis.qmd --to pdf

LaTeX from Python, Jupyter, and Julia

Jupyter / Python: Markdown cells render $...$ and $...$ via MathJax, so notebooks display typeset math with no extra setup. Exporting to PDF (jupyter nbconvert --to pdf) uses LaTeX under the hood.
Julia: Quarto and Pluto/Documenter notebooks render the same LaTeX math syntax; LaTeXStrings.jl lets you put LaTeX in plot labels.

Journal Templates

For submitting to journals, the rticles R package provides ready-made LaTeX templates for many publishers (PLOS, Elsevier, IEEE, and more). You write in R Markdown and get a correctly formatted PDF, no need to reverse-engineer a journal’s style file.

install.packages("rticles")
# In RStudio: New R Markdown -> From Template -> pick a journal