# Adding index entries

To add entries to the index, they must be manually specified within the `md` files.

There are two types [](style:index:inline) and [](style:index:directive)

(style:index:inline)=
## Inline

`:index:` should be used when adding unchanged keywords to the index. 

For example, to add an occurrence of `bellman equation` to the index within a paragraph you would simply wrap the words in an inline sphinx statement such as:

```
This is an example of adding {index}`bellman equation` to the index of a document
```

(style:index:directive)=
## Directives

```{note}
There is currently limited support for specifying multiple arguments in `jupyter book` for the `index` directive.
See [this issue](https://github.com/executablebooks/sphinx-tomyst/issues/36) for the latest update.
```

Directives are useful when adding more complex arangements to an index (such as nested entries) in addition
to times when using the inline syntax reduces readability of the `md` file. 

The directive attaches itself to the position of the next paragraph in the file. 

Adding a simple item to the index can be done by writing:

````
```{index} single: Bellman Equation
```
````

However more complex arrangements can also be specified, such as

````
```{index} single: Dynamic Programming; Bellman Equation
```
````

This would add `Bellman Equation` (with its associated page reference) underneath `Dynamic Programming` in the index.

## Additional info

Additional documentation can be found here: [http://sphinx-doc.org/markup/misc.html#index-generating-markup](http://sphinx-doc.org/markup/misc.html#index-generating-markup)

```{note}
Index items are case sensitive so care should be taken to be case consistent when specifying labels.
```