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% Generated by roxygen2: do not edit by hand
% Please edit documentation in R/iterators.R
\name{igraph-es-attributes}
\alias{igraph-es-attributes}
\alias{[[<-.igraph.es}
\alias{[<-.igraph.es}
\alias{$.igraph.es}
\alias{$<-.igraph.es}
\alias{E<-}
\title{Query or set attributes of the edges in an edge sequence}
\usage{
\method{[[}{igraph.es}(x, i) <- value
\method{[}{igraph.es}(x, i) <- value
\method{$}{igraph.es}(x, name)
\method{$}{igraph.es}(x, name) <- value
E(x, path = NULL, P = NULL, directed = NULL) <- value
}
\arguments{
\item{x}{An edge sequence. For \verb{E<-} it is a graph.}
\item{i}{Index.}
\item{value}{New value of the attribute, for the edges in the edge
sequence.}
\item{name}{Name of the edge attribute to query or set.}
\item{path}{Select edges along a path, given by a vertex sequence See
\code{\link[=E]{E()}}.}
\item{P}{Select edges via pairs of vertices. See \code{\link[=E]{E()}}.}
\item{directed}{Whether to use edge directions for the \code{path} or
\code{P} arguments.}
}
\value{
A vector or list, containing the values of the attribute
\code{name} for the edges in the sequence. For numeric, character or
logical attributes, it is a vector of the appropriate type, otherwise
it is a list.
}
\description{
The \code{$} operator is a syntactic sugar to query and set
edge attributes, for edges in an edge sequence.
}
\details{
The query form of \code{$} is a shortcut for \code{\link[=edge_attr]{edge_attr()}},
e.g. \code{E(g)[idx]$attr} is equivalent to \code{edge_attr(g, attr, E(g)[idx])}.
The assignment form of \code{$} is a shortcut for
\code{\link[=set_edge_attr]{set_edge_attr()}}, e.g. \code{E(g)[idx]$attr <- value} is
equivalent to \code{g <- set_edge_attr(g, attr, E(g)[idx], value)}.
}
\examples{
# color edges of the largest component
largest_comp <- function(graph) {
cl <- components(graph)
V(graph)[which.max(cl$csize) == cl$membership]
}
g <- sample_(
gnp(100, 1 / 100),
with_vertex_(size = 3, label = ""),
with_graph_(layout = layout_with_fr)
)
giant_v <- largest_comp(g)
E(g)$color <- "orange"
E(g)[giant_v \%--\% giant_v]$color <- "blue"
plot(g)
}
\seealso{
Other vertex and edge sequences:
\code{\link{E}()},
\code{\link{V}()},
\code{\link{as_ids}()},
\code{\link{igraph-es-indexing}},
\code{\link{igraph-es-indexing2}},
\code{\link{igraph-vs-attributes}},
\code{\link{igraph-vs-indexing}},
\code{\link{igraph-vs-indexing2}},
\code{\link{print.igraph.es}()},
\code{\link{print.igraph.vs}()}
}
\concept{vertex and edge sequences}
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