Fieldnotesv1.1.2
  1. Docs
  2. Writing

Maths and code

Formulas with MathJax, and code in your colour scheme’s colours.

Turning maths on

Two things: Markdown must leave formulas alone, and the page must load MathJax.

The first is the passthrough setting in hugo.toml, part of the starter settings:

hugo.toml 
[markup.goldmark.extensions.passthrough]
  enable = true
  [markup.goldmark.extensions.passthrough.delimiters]
    block = [['\[', '\]'], ['$$', '$$']]
    inline = [['\(', '\)']]

The second, per page in its front matter:

md 
---
title: "Error estimates"
math: true
---

or for every page with params.math = true in hugo.toml (a page can then say math: false). MathJax loads only on pages with maths turned on.

Writing formulas

LaTeX, between \( and \) in a sentence, and between $$ lines on its own:

md 
Euler's identity \(e^{i\pi} + 1 = 0\) and an integral:

$$
\int_0^1 x^2 \, dx = \frac{1}{3}
$$

\[ and \] work for formulas on their own line too. Dollar signs in a sentence ($x$) don’t, so prices like $5 stay prices.

Long formulas on phones

In a sentence, a formula breaks across lines like words. A formula on its own line that is too wide for a phone scrolls sideways in its own box, and so does one in a sentence that can’t break, so the page never scrolls sideways.

Code

md 
```python
def trapezoid(f, a, b, n):
    h = (b - a) / n
    return h * (f(a) / 2 + sum(f(a + i * h) for i in range(1, n)) + f(b) / 2)
```

Code takes its colours from the colour scheme: comments in its secondary colour, keywords in its primary colour, strings and numbers in its accent. Every code block has a copy button in its top-right corner (on hover with a mouse, always on touch screens).

Hugo’s options for code work, for example highlighted lines and line numbers:

md 
```go {hl_lines=[2] linenos=true}
func main() {
	fmt.Println("hello")
}
```

Hugo highlights hundreds of languages.