I'm trying to give a dynamically assigned id for a div inside a \*ngFor. I would like the divs to be called 'wave1, wave2, wave3' etc.

```html
<li *ngFor="let episode of episodes; let i = index">
    <div id="wave{{i}}"></div>
</li>

```

However, this throws the following error:

> 
> ERROR DOMException: Failed to execute 'querySelector' on 'Document':
> '#wave[object Object]' is not a valid selector.
> 
> 
>