TeX formulae

Quarkdown natively supports TeX math equations and formulae. When rendering to HTML, this feature is powered by KaTeX.

Inline

Inline equations can be created by wrapping text between two $ symbols. Both delimiters must be preceded and followed by a whitespace (or beginning/end of the line).

Example 1

Let $ \overline v = \frac {\Delta x} {\Delta t} $ be the **average velocity** of an object.

Let \overline v = \frac {\Delta x} {\Delta t} be the average velocity of an object.

One-line block

Block equations are usually visually centered and share the same syntax as inline ones, but need to be isolated from other content:

Example 2

The following function is a **Fourier Transform**:

$ F(u) = \int^{+\infty}_{-\infty} f(x) e^{-i 2\pi x} dx $

The following function is a Fourier Transform:

F(u) = \int^{+\infty}_{-\infty} f(x) e^{-i 2\pi x} dx

This syntax does not interrupt paragraphs, so make sure to space blocks properly. If the paragraph is not interrupted, the formula is recognized as inline due to Markdown’s lazy lines.
Example 3
The following function is a **Fourier Transform**:
$ F(u) = \int^{+\infty}_{-\infty} f(x) e^{-i 2\pi x} dx $
The following function is a Fourier Transform: F(u) = \int^{+\infty}_{-\infty} f(x) e^{-i 2\pi x} dx

Multiline block

A block formula can span over multiple lines thanks to a syntax similar to fenced code blocks, using three $ symbols as delimiters.

Example 4

$$$
f(x) =
\begin{cases}
    0 & \text{if } x = 0 \\
    1 & \text{if } x \neq 0
\end{cases}
$$$

f(x) = \begin{cases} 0 & \text{if } x = 0 \\ 1 & \text{if } x \neq 0 \end{cases}

The `.math` function

Equations can also be created via the .math primitive function. This is useful when the equation content is computed from other functions, or when you want to apply styling to a specific formula.

Example 5

.math
    E = mc^2

<!-- or, equivalently -->

.math {E = mc^2}

E = mc^2E = mc^2

By default, .math produces a block formula when produced by a block function call. You can force one or the other via the block parameter:

Example 6

Inline: .math {2 + 2}

Inline: 2 + 2

The content is evaluated as Quarkdown, so nested function calls are evaluated, contrary to the $-based syntax.

Example 7

.var {n} {5}

.math
    f(.n) = .n::multiply {2}

f(5) = 10

Styling

Both inline and block equations accept the same styling properties as containers.

Example 8

.math fontsize:{larger}
    \pi \approx 3.14

\pi \approx 3.14

Extending

.math backs the standard $ ... $ syntax, so extending it affects every equation in the document at once.

Example 9

.extend {math}
    .super foreground:{skyblue}

.extend {math} where:{block: .block}
    .super fontsize:{larger}

$ a^2 + b^2 = c^2 $

Inline: $ a^2 + b^2 = c^2 $

a^2 + b^2 = c^2

Inline: a^2 + b^2 = c^2

Macros

Quarkdown supports the creation of TeX macros via the .texmacro function. See TeX macros for more information.