This is a helper function that simplifies adding and deleting vertices to/from graphs.
Value
A special object that can be used with together with igraph graphs and the plus and minus operators.
Details
vertices() is an alias for vertex().
When adding vertices via +, all unnamed arguments are interpreted
as vertex names of the new vertices. Named arguments are interpreted as
vertex attributes for the new vertices.
When deleting vertices via -, all arguments of vertex() (or
vertices()) are concatenated via c() and passed to
delete_vertices().
See also
Other functions for manipulating graph structure:
+.igraph(),
add_edges(),
add_vertices(),
complementer(),
compose(),
connect(),
contract(),
delete_edges(),
delete_vertices(),
difference(),
difference.igraph(),
disjoint_union(),
edge(),
igraph-minus,
intersection(),
intersection.igraph(),
path(),
permute(),
rep.igraph(),
reverse_edges(),
simplify(),
union(),
union.igraph()
Examples
g <- make_(ring(10), with_vertex_(name = LETTERS[1:10])) +
vertices("X", "Y")
g
#> IGRAPH 4bad29e UN-- 12 10 -- Ring graph
#> + attr: name (g/c), mutual (g/l), circular (g/l), name (v/c)
#> + edges from 4bad29e (vertex names):
#> [1] A--B B--C C--D D--E E--F F--G G--H H--I I--J A--J
plot(g)
