deathFunction {rSHAPE}

This allows SHAPE to simulate the death process as a deterministic value, and may be density dependent.

Description

This allows SHAPE to simulate the death process as a deterministic value, and may be density dependent.

Usage

deathFunction(func_inSize, func_inProb = 0, func_roundValues = TRUE,
  func_depDensity = FALSE, func_densityMax = NULL,
  func_densityPower = 4)

Arguments

func_inSize

This is the vector of population sizes within the community

func_inProb

This is the general death probability defined for this run of SHAPE

func_roundValues

This is a logical toggle to define if the number of births and deaths are forced to be tracked as integer values. If TRUE, then any fractional amounts will be stochastically rounded to the nearest integer with a probability of being rounded up equal to the decimal value – ie: 0.32 means 32% chance of being rounded up –

func_depDensity

This is a logical toggle as to whether or not the calculation is density dependent. If TRUE, then func_densityMax reuqires a value.

func_densityMax

This is the community size at which maximum density dependent deaths (ie: 100% of func_inSize) occur.

func_densityPower

This is a scaling factor that controls the rate of transition between minimal and maximal values of the density dependent deaths. Higher values mean a steeper transition such that there are fewer deaths until higher densities are reached.

Value

A vector of the number of deaths caluclated for each of the populations represented by the func_inSize vector

Examples

# Imagine you've got an evolving community of three populations where in each time step
# 100% of individuals die.
deathFunction(func_inSize = c(100,50,200), func_inProb = 1)
# What if their deaths were scaled based on population density,
# or an environmental carrying capacity?
deathFunction(func_inSize = c(100,50,200), func_inProb = 1,
              func_depDensity = TRUE, func_densityMax = 400)
deathFunction(func_inSize = c(100,50,200), func_inProb = 1,
              func_depDensity = TRUE, func_densityMax = 500)
deathFunction(func_inSize = c(100,50,200), func_inProb = 1,
              func_depDensity = TRUE, func_densityMax = 350)