# Add math formulae with LaTeX

**Warning: this guide is recommended for advanced users and math students only! Here be LaTeX dragons.**

Coggle supports the LaTeX math syntax (via MathJax) for adding math formulae and expressions to Coggle diagrams. This guide introduces some simple examples, we'd recommend the LaTeX Mathematics wikibook for a more advanced guide to LaTeX.

Note that Coggle only supports LaTeX math expressions, not text-mode commands.

### Simple Math Expressions

Here’s a really simple math expression to get started:

Here the whole expression is actually entered into the text box asa simple LaTeX formula:

\\( \pi = 3.14159... \\)That looks quite different to what’s displayed, but we’ll break it down. Firstly, the

`\\(`

and
`\\)`

at the start and end mark the beginning and end of the block of math, that leaves us with:
\pi = 3.14159...

inside the math block. The next thing we get to is `\pi`

, which is just the LaTeX way of writing the greek letter pi. You’ll notice that the backslash \ is used to start almost all special LaTeX expressions. Finally, we just have a plain equals sign, number, and some periods, which are all included in the displayed text with no special interpretation.

### Matrices

Here’s a more complex example of how to display a matrix, we’ll explain the syntax below:

The syntax looks like this:

\\( \begin{pmatrix} 1 & 0 \\\ 0 & 1 \\\ \end{pmatrix} \\)

As before, all the text within `\\( \\)`

is interpreted as LaTeX. the `\begin{matrix} ... \end{pmatrix}`

block defines the sort of matrix that will be displayed (here’s a list of others). `&`

separates the columns of the matrix, and `\\\`

ends each row of the matrix. Note that there’s a small difference here to standard LaTeX: for technical reasons you need to use `\\\`

( **three** backwards slashes) to end a line instead of the normal two.

### Something More Complex

Finally, let’s look at something more complex. Here’s something that’s important to lots of science and maths students because of it’s so widely applicable in statistics: the Normal Distribution.

Pretty complex! Here’s the text to produce the 2D normal distribution:

\\[ \int_{-\infty}^{x} e^{\frac{-(t-\mu)^2}{2 \sigma^2}} \mathrm{d}t \\]And the text to produce the N-Dimensional normal distribution:

\\[ (2\pi)^{-\frac{k}{2}} |\boldsymbol\Sigma|^{-\frac{1}{2}} e^{ -\frac{1}{2}(\mathbf{x}-\boldsymbol\mu)'\boldsymbol\Sigma^{-1}(\mathbf{x}-\boldsymbol\mu) } \\]

Immediately you’ll notice that we’ve used `\\[`

and `\\]`

to start the math block, instead of `\\(`

and `\\)`

– this means the LaTeX is interpreted as if it’s on its own line, rather than sharing a line with other text. (Try adding text outside the maths blocks to see the effect of this). We’ll leave a full explanation of the syntax to the reader, (you’ll find the LaTeX/Mathematics wikibook very helpful!), but the best way to get started is just to copy and paste one of the expressions into a new Coggle of your own, edit the text and see what happens!

For the really interested, a full list of the supported LaTeX commands is available at mathjax.org, and you can see one of the Coggle team’s math demo Coggles here.