`link.vertex(index)`

Return the vertex at `index`

.

`link.vertex(index, vertex [, opt])`

Update the vertex at `index`

with value of `vertex`

. By default the new value is merged into the old value. Pass the `{ rewrite: true }`

option along to disregard the old value.

A vertex has only two properties, `x`

and `y`

. It may be defined as a g.Point object.

Example vertex:

```
link.vertex(0, {
x: 100,
y: 200
});
```

Note that all vertices are stored in an array on the link model under the attribute `vertices`

. Use the `link.vertices`

function to access the array.