rblnd {lacunaritycovariance}

Simulate a Boolean model of discs with log normal disc radii

Description

Simulates a Boolean model of discs with log normal radii by first simulating a Poisson point process and then placing discs of random radii around each point (the radii are generated using a log normal distribution).

Usage

rblnd(obswin, bufferdist, lambda, meanlog, sdlog, seed = NULL)

Arguments

obswin

An owin object specifying the desired simulation region

bufferdist

A distance to expand obswin so that discs with centres near obswin are also simulated.

lambda

Intensity of the Poisson point process, passed to rpoispp. It could be either a single positive number, or any other object that rpoispp can understand.

meanlog

For the distribution of radii. The logarithm of the distribution is set to have mean meanlog.

sdlog

For the distribution of radii. The logarithm of the distribution is set to have standard deviation sdlog

seed

Optional input (default is NULL). Is an integer passed to set.seed. Used to reproduce patterns exactly.

Details

The point process needs to be simulated in a larger region than the desired observation window to account for the possibility of discs that intersect the observation window, but have germs outside the observation window.

The point process of germs is generated using spatstat's rpoispp.

Value

Returns an owin object cropped to obswin.

Warning

A good choice of bufferdist is required and will be sensitive to the distribution of radii.

Examples

w <- owin(xrange = c(0, 10), yrange = c(0, 10))
xi <- rblnd(w, 2, 0.3, -1, 0.2)