Function rate

rate(json?): void
Set the speed of animation when the play button is pressed.

The value is a multiplier applied to time expressed in seconds, so 1 is realtime, 60 is one minute per second, 3600 is on hour per second.
Parameters
- json: {
  rate: number;
  } = ...
  - rate: number
    number: 1 to at least several million, at which point everything becomes a blur.
Returns void
Example
```
{rate: 60}
```