Get Tracked Attributes at a Given Time Step

Reconstructs the state of all tracked attributes at a specific time step from the delta-compressed attribute history. Returns a tibble with one row per active node and one column per tracked attribute.

Usage

get_attr_at(sim, at, sim_num = 1, compute_age = FALSE)

Arguments

sim

An EpiModel object of class netsim.

at

The time step at which to reconstruct attributes, on the time step labels of sim (see truncate_sim()). It must lie between the start of the attribute history and the last time step. The history starts at the first time step for a new simulation, and at start - 1 for a restarted one, whose history starts again from a full snapshot of the state it restarted from.

sim_num

The simulation number to use (default 1).

compute_age

If TRUE and age is tracked, compute the age of nodes at at from their last recorded age, assuming age in years and 364 days in a year. This needs a time.unit parameter (the number of days in a time step) in sim$param, passed to param.net or set by the initialization module (as EpiModelHIV does from its epistats).

Value

A tibble with columns unique_id, active, and one column per tracked attribute, containing the most recent value at or before at for each active node.

See also

record_attr_history(), get_attr_history()

Examples

# \donttest{
nw <- network_initialize(n = 100)
est <- netest(nw, formation = ~edges, target.stats = 50,
              coef.diss = dissolution_coefs(~offset(edges), 10),
              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.
control <- control.net(type = "SI", nsteps = 20, nsims = 1,
                       tracked.attributes = "status", verbose = FALSE)
sim <- netsim(est, param.net(inf.prob = 0.3, act.rate = 1),
              init.net(i.num = 10), control)

# The status of every node at time step 10
at10 <- get_attr_at(sim, at = 10)
head(at10)
#> # A tibble: 6 × 3
#>   unique_id active status
#>       <int>  <int> <chr> 
#> 1         1      1 i     
#> 2         2      1 i     
#> 3         3      1 i     
#> 4         4      1 s     
#> 5         5      1 s     
#> 6         6      1 s     
table(at10$status)
#> 
#>  i  s 
#> 36 64 
# }