Use this if you are using igraph from R
disjoint_union {igraph} | R Documentation |
The union of two or more graphs are created. The graphs are assumed to have disjoint vertex sets.
disjoint_union(...)
x %du% y
... |
Graph objects or lists of graph objects. |
x, y |
Graph objects. |
disjoint_union
creates a union of two or more disjoint graphs.
Thus first the vertices in the second, third, etc. graphs are relabeled to
have completely disjoint graphs. Then a simple union is created. This
function can also be used via the %du% operator.
graph.disjont.union
handles graph, vertex and edge attributes. In
particular, it merges vertex and edge attributes using the basic c()
function. For graphs that lack some vertex/edge attribute, the corresponding
values in the new graph are set to NA
. Graph attributes are simply
copied to the result. If this would result a name clash, then they are
renamed by adding suffixes: _1, _2, etc.
Note that if both graphs have vertex names (ie. a name
vertex
attribute), then the concatenated vertex names might be non-unique in the
result. A warning is given if this happens.
An error is generated if some input graphs are directed and others are undirected.
A new graph object.
Gabor Csardi csardi.gabor@gmail.com
## A star and a ring
g1 <- make_star(10, mode="undirected")
V(g1)$name <- letters[1:10]
g2 <- make_ring(10)
V(g2)$name <- letters[11:20]
print_all(g1 %du% g2)