Returns a population of individuals alive.
# S3 method for population
population_alive(object, t, a1 = 0, a2 = Inf, ...)
The function returns a population data frame containing all individuals alive at time t
and of age in [a1,a2)
.
A population data frame containing at least a column birth
and death
.
A numeric indicating the time.
0 by default. All individuals of age over a1
at t
are selected.
Inf by default. All individuals of age below a2
at t
are selected.
Additional params.