Difference of graphsSource:
The difference of two graphs are created.
# S3 method for igraph difference(big, small, byname = "auto", ...)
The left hand side argument of the minus operator. A directed or undirected graph.
The right hand side argument of the minus operator. A directed ot undirected graph.
A logical scalar, or the character scalar
auto. Whether to perform the operation based on symbolic vertex names. If it is
auto, that means
TRUEif both graphs are named and
FALSEotherwise. A warning is generated if
autoand one graph, but not both graphs are named.
Ignored, included for S3 compatibility.
difference() creates the difference of two graphs. Only edges
present in the first graph but not in the second will be be included in the
new graph. The corresponding operator is
byname argument is
auto and the graphs
are all named), then the operation is performed based on symbolic vertex
names. Otherwise numeric vertex ids are used.
difference() keeps all attributes (graph, vertex and edge) of the
small must both be directed or both be
undirected, otherwise an error message is given.
Other functions for manipulating graph structure:
Gabor Csardi email@example.com
## Create a wheel graph wheel <- union( make_ring(10), make_star(11, center = 11, mode = "undirected") ) V(wheel)$name <- letters[seq_len(vcount(wheel))] ## Subtract a star graph from it sstar <- make_star(6, center = 6, mode = "undirected") V(sstar)$name <- letters[c(1, 3, 5, 7, 9, 11)] G <- wheel %m% sstar print_all(G) #> IGRAPH e5cfa2f UN-- 11 15 -- #> + attr: name_1 (g/c), name_2 (g/c), mutual (g/l), circular (g/l), mode #> | (g/c), center (g/n), name (v/c) #> + edges (vertex names): #> a -- b, j #> b -- a, c, k #> c -- b, d #> d -- c, e, k #> e -- d, f #> f -- e, g, k #> g -- f, h #> h -- g, i, k #> i -- h, j #> j -- a, i, k #> k -- b, d, f, h, j plot(G, layout = layout_nicely(wheel))