Fast Version of network::add.vertices for Edgelist-formatted Network

This function performs a simple operation of updating the edgelist attribute n that tracks the total network size implicit in an edgelist representation of the network.

Usage

add_vertices(el, nv)

Arguments

el

A two-column matrix of current edges (edgelist) with an attribute variable n containing the total current network size.

nv

A integer equal to the number of nodes to add to the network size at the given time step.

Value

Returns the matrix of current edges, el, with the population size attribute updated based on the number of new vertices specified in nv.

Details

This function is used in EpiModel modules to add vertices (nodes) to the edgelist object to account for entries into the population (e.g., births and in-migration).

Examples

library("EpiModel")
nw <- network_initialize(100)
formation <- ~edges
target.stats <- 50
coef.diss <- dissolution_coefs(dissolution = ~offset(edges), duration = 20)
x <- netest(nw, formation, target.stats, coef.diss, verbose = FALSE)
#> Starting simulated annealing (SAN)
#> Iteration 1 of at most 4
#> Finished simulated annealing
#> Starting maximum pseudolikelihood estimation (MPLE):
#> Obtaining the responsible dyads.
#> Evaluating the predictor and response matrix.
#> Maximizing the pseudolikelihood.
#> Finished MPLE.

param <- param.net(inf.prob = 0.3)
init <- init.net(i.num = 10)
control <- control.net(type = "SI", nsteps = 100, nsims = 5,
                       tergmLite = TRUE, resimulate.network = TRUE)

# Edgelist representation after initialization
crosscheck.net(x, param, init, control)
dat <- initialize.net(x, param, init, control, s = 1)
el <- get_edgelist(dat, network = 1)

# Check current network size
attributes(el)$n
#> [1] 100

# Add 10 vertices
el <- add_vertices(el, 10)

# Check new network size
attributes(el)$n
#> [1] 110