network.edgecount {network} | R Documentation |
Return the Number of Edges in a Network Object
Description
network.edgecount
returns the number of edges within a
network
, removing those flagged as missing if desired.
Usage
## S3 method for class 'network'
network.edgecount(x, na.omit = TRUE, ...)
Arguments
x |
an object of class |
na.omit |
logical; omit edges with |
... |
additional arguments, used by extending functio |
Details
The return value is the number of distinct edges within the network object, including multiplex edges as appropriate. (So if there are 3 edges from vertex i to vertex j, each contributes to the total edge count.)
The return value network.edgecount
is in the present implementation
related to the (required) mnext
network attribute. mnext
is
an internal legacy attribute that currently indicates the index number of
the next edge to be added to a network object. (Do not modify it unless you
enjoy unfortunate surprises.) The number of edges returned by
network.edgecount
is equal to x%n%"mnext"-1
, minus the number
of NULL
edges (and missing edges, if na.omit==TRUE
). Note
that g%n%"mnext"-1
cannot, by itself, be counted upon to be an
accurate count of the number of edges! As mnext
is not part of the
API (and is not guaranteed to remain), users and developers are urged to use
network.edgecount
instead.
Value
The number of edges
Warning
network.edgecount
uses the real state of the
network object to count edges, not the state it hypothetically should have.
Thus, if you add extra edges to a non-multiplex network, directed edges to
an undirected network, etc., the actual number of edges in the object will
be returned (and not the number you would expect if you relied only on the
putative number of possible edges as reflected by the
network.indicators). Don't create network
objects with
contradictory attributes unless you know what you are doing.
Author(s)
Carter T. Butts buttsc@uci.edu
References
Butts, C. T. (2008). “network: a Package for Managing Relational Data in R.” Journal of Statistical Software, 24(2). https://www.jstatsoft.org/v24/i02/
See Also
Examples
#Create a network with three edges
m<-matrix(0,3,3)
m[1,2]<-1; m[2,3]<-1; m[3,1]<-1
g<-network(m)
network.edgecount(g)==3 #Verify the edgecount