| graph.data.frame {igraph} | R Documentation |
This function creates an igraph graph from one or two data frames containing the (symbolic) edge list and edge/vertex attributes.
graph.data.frame(d, directed=TRUE, vertices=NULL)
d |
A data frame containing a symbolic edge list in the first two columns. Additional columns are considered as edge attributes. |
directed |
Logical scalar, whether or not to create a directed graph. |
vertices |
A data frame with vertex metadata, or NULL. See
details below. |
graph.data.frame creates igraph graphs from one or two data
frames. It has two modes of operatation, depending whether the
vertices argument is NULL or not.
If vertices is NULL, then the first two columns of
d are used as a symbolic edge list and additional columns as
edge attributes. The names of the attributes are taken from the names
of the columns.
If vertices is not NULL, then it must be a data frame
giving vertex metadata. The first column of vertices is assumed
to contain symbolic vertex names, this will be added to the graphs as
the ‘name’ vertex attribute. Other columns will be added
as additional vertex attributes. If vertices is not NULL
then the symbolic edge list given in d is checked to contain
only vertex names listed in vertices.
Typically, the data frames are exported from some speadsheat software
like Excel and are imported into R via read.table,
read.delim or read.csv.
An igraph graph object.
Gabor Csardi csardi@rmki.kfki.hu
graph.constructors and
graph.formula for other ways to create graphs,
read.table to read in tables from files.
## A simple example with a couple of actors
## The typical case is that these tables are read in from files....
actors <- data.frame(name=c("Alice", "Bob", "Cecil", "David",
"Esmeralda"),
age=c(48,33,45,34,21),
gender=c("F","M","F","M","F"))
relations <- data.frame(from=c("Bob", "Cecil", "Cecil", "David",
"David", "Esmeralda"),
to=c("Alice", "Bob", "Alice", "Alice", "Bob", "Alice"),
same.dept=c(FALSE,FALSE,TRUE,FALSE,FALSE,TRUE),
friendship=c(4,5,5,2,1,1), advice=c(4,5,5,4,2,3))
g <- graph.data.frame(relations, directed=TRUE, vertices=actors)
print(g, e=TRUE, v=TRUE)