\name{graphAM-class}
\docType{class}
\alias{graphAM-class}
\alias{addEdge,character,character,graphAM,missing-method}
\alias{addNode,character,graphAM,missing-method}
\alias{clearNode,character,graphAM-method}
\alias{coerce,graphAM,graphNEL-method}
\alias{coerce,graphAM,matrix-method}
\alias{coerce,matrix,graphAM-method}
\alias{coerce,graphAM,graphBAM-method}
\alias{edges,graphAM,missing-method}
\alias{edges,graphAM,character-method}
\alias{initialize,graphAM-method}
\alias{inEdges,missing,graphAM-method}
\alias{inEdges,character,graphAM-method}
\alias{inEdges,graphAM,missing-method}
\alias{isAdjacent,graphAM,character,character-method}
\alias{nodes<-,graphAM,character-method}
\alias{nodes,graphAM-method}
\alias{numEdges,graphAM-method}
\alias{numNodes,graphAM-method}
\alias{removeEdge,character,character,graphAM-method}
\alias{removeNode,character,graphAM-method}

\title{Class "graphAM"}

\description{
  A graph class where node and edge information is represented as an
  adjacency matrix.  The adjacency matrix is square and element
  \code{adjMat[i, j]} is one if there is an edge from node i to
  node j and zero otherwise.
}

\details{
  The non-zero matrix values can be used to initialize an edge
  attribute.  If this is desired, use the \code{values} argument in the
  call to \code{new} and provide a list with a single named element.
  The name determines the attributes and the value provides the default
  value for that attribute.
}

\section{Objects from the Class}{
Objects can be created by calls of the form \code{new("graphAM", adjMat, edgemode, values)}.
}
\section{Slots}{
  \describe{
    \item{\code{adjMat}:}{An adjacency \code{"matrix"} describing the
    graph structure.  The \code{\link{colnames}} of the matrix will be used as
    node names for the graph if present.}
    \item{\code{edgeData}:}{Storage for edge attributes.}
    \item{\code{nodeData}:}{Storage for node attributes.}
  }
}
\section{Extends}{
Class \code{"graph"}, directly.
}
\section{Methods}{
  \describe{
    \item{addEdge}{\code{signature(from = "character", to = "character", graph = "graphAM", weights = "missing")}: ... }
    \item{addNode}{\code{signature(object = "graphAM", nodes = "character")}: ... }
    \item{clearNode}{\code{signature(node = "character", object = "graphAM")}: ... }
    \item{coerce}{\code{signature(from = "graphAM", to = "graphNEL")}: ... }
    \item{coerce}{\code{signature(from = "graphAM", to = "graphBAM")}: ... }
    \item{coerce}{\code{signature(from = "graphAM", to = "matrix")}: In
      converting to a \code{matrix}, if an edge attribute named
      \code{"weight"} is defined, the non-zero elements of the matrix
      will contain the corresponding attribute value.  For more flexible
      matrix conversion, see \code{toMatrix}.}
    \item{coerce}{\code{signature(from = "matrix", to = "graphAM")}:
      This coerce method exists for symmetry.  In most cases, creating a
      new \code{graphAM} instance using \code{new} gives one more
      control over the resulting graph.}
    \item{edges}{\code{signature(object = "graphAM", which = "missing")}: ... }
    \item{edges}{\code{signature(object = "graphAM", which = "character")}: ... }
    \item{initialize}{\code{signature(.Object = "graphAM")}: ... }
    \item{inEdges}{\code{signature(node = "character", object =
        "graphNEL")}: Return the incoming edges for the specified
      nodes.  See \code{\link{inEdges}}.}
    \item{isAdjacent}{\code{signature(object = "graphAM", from = "character", to = "character")}: ... }
    \item{nodes<-}{\code{signature(object = "graphAM", value = "character")}: ... }
    \item{nodes}{\code{signature(object = "graphAM")}: ... }
    \item{numEdges}{\code{signature(graph = "graphAM")}: ... }
    \item{numNodes}{\code{signature(object = "graphAM")}: ... }
    \item{removeEdge}{\code{signature(from = "character", to = "character", graph = "graphAM")}: ... }
    \item{removeNode}{\code{signature(node = "character", object = "graphAM")}: ... }
  }
}
\author{Seth Falcon}

\seealso{
  \code{\link{graph-class}}, \code{\link{graphNEL-class}}
}
\examples{
mat <- rbind(c(0, 0, 1, 1),
             c(0, 0, 1, 1),
             c(1, 1, 0, 1),
             c(1, 1, 1, 0))
rownames(mat) <- colnames(mat) <- letters[1:4]
g1 <- new("graphAM", adjMat=mat)
stopifnot(identical(mat, as(g1, "matrix")), validObject(g1))

## now with weights:
mat[1,3] <- mat[3,1] <- 10
gw <- new("graphAM", adjMat=mat, values=list(weight=1))

## consistency check:
stopifnot(identical(mat, as(gw, "matrix")),
          validObject(gw),
          identical(gw, as(as(gw, "graphNEL"), "graphAM")))
}
\keyword{graphs}
\keyword{classes}