ergm (version 3.0-3)

edgelist.ergm: Return edgelist in standard ergm format

Description

edgelist.ergm returns an edgelist for a network in a format that is expected by many of the routines of the ergm package.

Usage

## S3 method for class 'default':
edgelist.ergm(x,\dots)
## S3 method for class 'network':
edgelist.ergm(x, \dots)
## S3 method for class 'matrix':
edgelist.ergm(x, directed=TRUE, check.uniqueness=TRUE,
                               check.sorted=TRUE, \dots)

Arguments

x

an Robject. Either a network or a matrix of some sort.

directed

logical: Are the edges directed? If x is a square matrix with NROWS(x)!=2, equal to !all(x==t(x))

check.uniqueness

An edgelist should have unique rows. By default, therefore, uniqueness is checked. However, if the input is known to have unique rows already, then setting this option to FALSE will save computing time

check.sorted

An edgelist should have its rows sorted in dictionary order. By default, therefore, the matrix is checked to see whether it is sorted. However, if the input is known to be sorted already, then setting this option to FALSE will save computing time.

...

Additional arguments, to be passed to lower-level functions in the future.

Value

• A matrix with two rows, in the format described under "Details"

Details

The function takes a network or an (adjacency or edgelist) matrix, then returns an edgelist (of class "matrix") in standard format. If x is a network, the value returned equals edgelist.ergm(as.matrix(x, "edgelist"), directed=is.directed(x)). The standard format is as follows:

1. The matrix has two columns

2. No row has two identical entries

3. Each row is unique

4. The rows are in dictionary order: They are sorted by the first column, then by the second in case of ties 5. If directed=TRUE, the element in the first column is always smaller than the element in the second column (otherwise, the entries in that row are switched before sorting).

See Also

as.matrix.network