graph_from_incidence_matrix()
creates a bipartite igraph graph from an incidence
matrix.
Usage
graph_from_incidence_matrix(
incidence,
directed = FALSE,
mode = c("all", "out", "in", "total"),
multiple = FALSE,
weighted = NULL,
add.names = NULL
)
from_incidence_matrix(...)
Arguments
- incidence
The input incidence matrix. It can also be a sparse matrix from the
Matrix
package.- directed
Logical scalar, whether to create a directed graph.
- mode
A character constant, defines the direction of the edges in directed graphs, ignored for undirected graphs. If ‘
out
’, then edges go from vertices of the first kind (corresponding to rows in the incidence matrix) to vertices of the second kind (columns in the incidence matrix). If ‘in
’, then the opposite direction is used. If ‘all
’ or ‘total
’, then mutual edges are created.- multiple
Logical scalar, specifies how to interpret the matrix elements. See details below.
- weighted
This argument specifies whether to create a weighted graph from the incidence matrix. If it is
NULL
then an unweighted graph is created and themultiple
argument is used to determine the edges of the graph. If it is a character constant then for every non-zero matrix entry an edge is created and the value of the entry is added as an edge attribute named by theweighted
argument. If it isTRUE
then a weighted graph is created and the name of the edge attribute will be ‘weight
’.- add.names
A character constant,
NA
orNULL
.graph_from_incidence_matrix()
can add the row and column names of the incidence matrix as vertex attributes. If this argument isNULL
(the default) and the incidence matrix has both row and column names, then these are added as the ‘name
’ vertex attribute. If you want a different vertex attribute for this, then give the name of the attributes as a character string. If this argument isNA
, then no vertex attributes (other than type) will be added.- ...
Passed to
graph_from_incidence_matrix()
.
Details
Bipartite graphs have a ‘type
’ vertex attribute in igraph,
this is boolean and FALSE
for the vertices of the first kind and
TRUE
for vertices of the second kind.
graph_from_incidence_matrix()
can operate in two modes, depending on the
multiple
argument. If it is FALSE
then a single edge is
created for every non-zero element in the incidence matrix. If
multiple
is TRUE
, then the matrix elements are rounded up to
the closest non-negative integer to get the number of edges to create
between a pair of vertices.
See also
make_bipartite_graph()
for another way to create bipartite
graphs
Author
Gabor Csardi csardi.gabor@gmail.com