This function returns another function that can extract nodes from a
ggraph_layout object. As a ggraph_layout object is essentially a data.frame
of nodes it might seem useless to provide this function, but since the node
data is not necessarily available until after the ggraph()
call it
can be beneficial to be able to add information to the node data on a
per-layer basis. Unlike get_edges()
the use of get_nodes
is not
mandatory and is only required if additional data should be added to selected
node layers.
get_sf_nodes()
get_nodes(...)
Additional data that should be cbind'ed together with the node data. Accepts expressions that will be evaluated on the node data in it's original order (irrespective of any reordering by the layout)
A data.frame with the node data as well of any additional data
supplied through ...