R/mode-counts.R

In corybrunson/bitriad: Triadic Analysis of Affiliation Networks

#' @title Count the actors and events in an affiliation network
#'   
#' @description These functions return the number of actors (nodes with 
#'   \code{type} attribute \code{FALSE}) or events (\code{TRUE}) in an 
#'   affiliation network.
#'   
#' @name mode_counts
#' @family modal queries and manipulations
#' @seealso Original \strong{igraph} functions: \code{\link[igraph]{vcount}},
#'   \code{\link[igraph]{ecount}}
#' @param graph An affiliation network.
#' @examples
#' data(chicago1960s)
#' actor_count(chicago1960s)
#' event_count(chicago1960s)
NULL

#' @rdname mode_counts
#' @export
actor_count <- function(graph) {
  stopifnot(is_an(graph))
  if (vcount(graph) == 0) return(0)
  length(which(!V(graph)$type))
}

#' @rdname mode_counts
#' @export
event_count <- function(graph) {
  stopifnot(is_an(graph))
  if (vcount(graph) == 0) return(0)
  length(which(V(graph)$type))
}

#' @rdname mode_counts
#' @export
actor.count <- actor_count

#' @rdname mode_counts
#' @export
event.count <- event_count