predictFutureDistribution: Predicts continuous (e.g. size) stage distribution in the...

In wpetry/IPMpack2: Builds and analyses Integral Projection Models (IPMs).

Predicts continuous (e.g. size) stage distribution in the future giving current population's stage distribution.

Description

Function to project a population forwards using an IPM and a starting environment. The IPM may be structured by continuous (e.g. size) stage alone, or by continuous stage and environment.

Usage

predictFutureDistribution(startingSizes, IPM, n.time.steps, startingEnv = 1)

Arguments

startingSizes	vector containing the sizes of the desired starting population.
IPM	an IPMmatrix object (P matrix if only interested in survival projections, P matrix+ F matrix otherwise).
n.time.steps	a numeric defining the number of time steps for which projection is required.
startingEnv	vector defining the desired starting environment, of length one or length startingSizes; ignored if no environmental states are provided; otherwise if the length is less than startingSizes assumes all individuals start in the same environment, given by startingEnv[1].

Details

Currently this does not accept IPMs with discrete stages (e.g. seedbank).

Value

n.new.dist0	starting frequency distribution along meshpoints in IPMmatrix.
n.new.dist	final frequency distribution.

Author(s)

C. Jessica E. Metcalf, Sean M. McMahon, Roberto Salguero-Gomez, Eelke Jongejans & Cory Merow.

Examples

# Define starting population of interest
startPop <- rnorm(1000,2,1)

# Build T and F matrix
dff <- generateData()
Pmatrix <- makeIPMPmatrix(minSize = 1.1*min(dff$size, na.rm = TRUE),
maxSize = 1.1*max(dff$size, na.rm = TRUE), growObj = makeGrowthObj(dff),
survObj = makeSurvObj(dff), correction = "constant")
Fmatrix <- makeIPMFmatrix(minSize = 1.1*min(dff$size, na.rm = TRUE),
maxSize = 1.1*max(dff$size, na.rm = TRUE), 
fecObj = makeFecObj(dff, fecConstants = data.frame(est=0.7), Transform="log"), 
correction="constant")

# Make an IPMmatrix object containing P matrix + F matrix 
# by replacing the P matrix
IPM <- Pmatrix
IPM@.Data <- Pmatrix + Fmatrix

# Project population five steps
a5 <- predictFutureDistribution(startingSizes = startPop, IPM = IPM,
n.time.steps = 5, startingEnv = 1)

wpetry/IPMpack2 documentation built on Sept. 29, 2022, 9:41 a.m.