`(graph-vertex-update (G <graph>) vertex [#!rest attr])`method`(graph-vertex-update! (G <graph>) vertex [#!rest attr])`methodUpdates the vertex attributes for a vertex in graph G. Raises an error if the vertex does not exist within the graph.

- G
- the graph to update
- vertex
- the vertex whose attributes you wish to modify
- attr
- a series of keyword / value pairs which describe attributes to add to the vertex

E.g.:

(graph-vertex-update G 'a colour: "red" size: 4)