cranet: Build and Analyze Network of R Packages

#' Snapshot of CRAN packages
#'
#' Snapshot of CRAN packages made on 2016-08-12
#'
#' @format 
#' The network object is of class \code{igraph}. It is a directed network which
#' contains \Sexpr{igraph::vcount(cranet::crannet)} packages (vertices) and 
#' \Sexpr{igraph::ecount(cranet::crannet)} inter-package relations (edges). The
#' network, together with vertex and edge attributes is build from the matrix as
#' returned by \code{\link{available.packages}}, which in turn is based on
#' package DESCRIPTION files.
#' 
#' Available edge attributes: 
#' \Sexpr{paste( igraph::list.edge.attributes(cranet::crannet), collapse=", ")}
#' 
#' Available vertex attributes:
#' \Sexpr{paste( igraph::list.vertex.attributes(cranet::crannet), collapse=", ")}. 
#' 
#' The network is a multi-graph, i.e. there may be multiple edges between a 
#' given pair of nodes. This corresponds to the fact, that package X may, for 
#' example, both depend and import package Y.  To disentangle the types of 
#' relations one can use edge attribute \code{type} which identifies a type of 
#' inter-package relation. Possible values are of this attribute are: 
#' \Sexpr{paste( sort(unique(igraph::E(cranet::crannet)$type)), collapse=", ")}.
#' They come from the respective columns in the matrix returned by
#' \code{\link{available.packages}}.
#' 
#' See \code{\link{available.packages}} for the description of the attributes
#' and types of inter-package relations.
#'
#' @source Fetched from \url{http://cran.at.r-project.org} on August 12, 2016.
#' @keywords datasets
#' @docType data
#' @name crannet
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