posum simulation {posum}R Documentation

Simulating Population Surface Models

Description

Routines that specify per capita death rate and recruitment functions for simulating population surface data

Usage

pcdr(a,t)

rec(t)

Arguments

a array of ages at which per capita death rates is required.
t array of times at which per capita death rates or recruitment rates are required.

Details

These functions are called by routines survival and population in order to calculate the population per unit age interval that they imply at any given age and time. The user should modify these functions in order to simulate from a different model. Note that they take array arguments.

Value

The functions returns arrays of recruitment rates or per capita death rates at the specified times or ages and times.

WARNING

Author(s)

Simon N. Wood snw@st-and.ac.uk

References

http://www.ruwpa.st-and.ac.uk/simon.html

See Also

death.surface, population, population.data, population.surface, sim.age.bound, survival,

Examples

old.pcdr<-pcdr;old.rec<-rec
pcdr<-function(a,t) {0*a+0.01} # constant pcdr function
rec<-function(t) {r<-t;r[t<0]<-1;r[t>=0]<-exp(-0.02*t[t>=0]);r} 
population.surface(10,10,30,con=TRUE)
death.surface(10,10,30,con=TRUE) 
rec<-old.rec;pcdr<-old.pcdr

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