Gives how to create the adjacency matrix for undirected
graphs. It is ignored for directed graphs. Possible values:
upper: the upper right triangle of the matrix is used,
lower: the lower left triangle of the matrix i
attr
Either NULL or a character string giving an edge
attribute name. If NULL a traditional adjacency matrix is
returned. If not NULL then the values of the given edge
attribute are included in the adjacency m
names
Logical constant.
For graph.adjacenct it gives whether to assign row and column names
to the matrix. These are only assigned if the name vertex
attribute is present in the graph.
for get.edgelist it
binary
Logical, whether to return a binary matrix. This argument
is ignored if attr is not NULL.
sparse
Logical scalar, whether to create a sparse matrix. The
Matrix package must be installed for creating sparse
matrices.
Value
A vcount(graph) by vcount(graph) (usually) numeric
matrix for get.adjacency. (This can be huge!) Note that a
non-numeric matrix might be returned if attr is a non-numeric
edge attribute.
A ecount(graph) by 2 numeric matrix for get.edgelist.
concept
Edge list
Adjacency list
Details
get.adjacency returns the adjacency matrix of a graph, a
regular Rmatrix if sparse is FALSE, or a sparse
matrix, as defined in the Matrix package, if
sparse if TRUE.
get.edgelist returns the list of edges in a graph.