Nodes are the vertices in the graph that are shared by "arcs".
sc_node(x, ...)
# S3 method for SC
sc_node(x, ...)
# S3 method for SC0
sc_node(x, ...)
# S3 method for default
sc_node(x, ...)
# S3 method for PATH
sc_node(x, ...)
# S3 method for ARC
sc_node(x, ...)
input object
arguments for methods
data frame of the nodes