Delete vertices or edges from a graph
# S3 method for igraph
-(e1, e2)An igraph graph.
Left argument, see details below.
Right argument, see details below.
The minus operator (‘-’) can be used to remove vertices
or edges from the graph. The operation performed is selected based on
the type of the right hand side argument:
If it is an igraph graph object, then the difference of the
two graphs is calculated, see difference.
If it is a numeric or character vector, then it is interpreted as a vector of vertex ids and the specified vertices will be deleted from the graph. Example:
g <- make_ring(10)
V(g)$name <- letters[1:10]
g <- g - c("a", "b")If e2 is a vertex sequence (e.g. created by the
V function), then these vertices will be deleted from
the graph.
If it is an edge sequence (e.g. created by the E
function), then these edges will be deleted from the graph.
If it is an object created with the vertex (or the
vertices) function, then all arguments of vertices are
concatenated and the result is interpreted as a vector of vertex
ids. These vertices will be removed from the graph.
If it is an object created with the edge (or the
edges) function, then all arguments of edges are
concatenated and then interpreted as edges to be removed from the
graph.
Example:
g <- make_ring(10)
V(g)$name <- letters[1:10]
E(g)$name <- LETTERS[1:10]
g <- g - edge("e|f")
g <- g - edge("H")If it is an object created with the path function,
then all path arguments are concatenated and then interpreted
as a path along which edges will be removed from the graph.
Example:
g <- make_ring(10)
V(g)$name <- letters[1:10]
g <- g - path("a", "b", "c", "d")Other functions for manipulating graph structure:
+.igraph(),
add_edges(),
add_vertices(),
delete_edges(),
delete_vertices(),
edge(),
path(),
vertex()