# How to use LaTeX Math in Draw.io & Diagrams.net models

Making publication-quality system models with complex mathematical notation can be a tedious task. In the past, I've been using Inkscape with TexText. This combination works fine and can produce great-quality images. However, I found it is not ideal for models that are basically diagrams. As the interconnections between the items and layout, in general, are hard to re-arrange.

Previously known as draw.io, diagrams.net has become a convenient tool for making complex system models. It supports has good support for mathematical typesetting that should feel familiar to anyone with a background in LaTeX.

This post will show you how to draw a system model for a downlink multi-user system with a full description of the system parameters embedded into the illustration.

Start by downloading or using the online version from diagrams.net. Choose `Change storage`

to pick the place where to save the model. For this example, I used `Device`

to store it on my laptop.

Type in the name of the file and choose the basic layout components. I used `Network`

as I will be using the predefined symbols for network diagrams.

After creating the empty diagram, enable the mathematical typesetting from `Extras -> Mathematical Typesetting`

. Diagrams.net has support for LaTeX and AsciiMath. LaTeX notation can be used inside the text elements by writing the expressions between `$$`

`$$`

or for inline version `\(`

`\)`

.

Next, we start placing the components. First, we pick the base station by using the `radio tower`

symbol. You find the symbols by using the search textbox. For the receivers, I used the `cell phone`

symbol.

This is our basic layout, which we will be filling with the mathematical notation.

You can modify the text objects from the right-hand side toolbar. For the receiver labels, I've used these settings.

Now, we plugin the math. I'll add \(g_n\) to denote the channel gains between the transmitter and the corresponding receiver. Further, I'll add SNR expression in general form and for Receiver 1 as an example.

All the math expressions are done by using conventional text elements. For instance, the general SNR expression is given by

```
$$
\gamma_n = {g_n p_n \over{ \sum_{i \neq n} g_n p_i + N_0 }}
$$
```

The model can be exported in common formats including SVG, PDF, and PNG for further processing.

It took me maybe 5 minutes to make this model. Far faster than the previous Inkscape + TexText combo.