| dispersal {pop} | R Documentation |
dispersal transfun
Description
Create a transfun object representing a relative probability of
dispersal between patches. Typically used inside a call to
transition
Usage
dispersal(value)
d(value)
is.dispersal(x)
Arguments
value |
the (positive) exponential rate of decay of dispersal probabilities. Large values imply shorter range dispersal. |
x |
an object to be tested as a dispersal transfun object |
Details
d() is a shorthand for dispersal(). The
transfun object returned, when applied to a landscape object,
produces a square symmetric matrix, with zero diagonal and off-diagonals
giving the relative between patch dispersal probability. This implies that
all individuals in the state will try to disperse. The
fraction remaining in the patch depends on value. To have only some
fraction try to disperse, a dispersal transfun can be multiplied by a
probability transfun indicating the probability of attempting dispersal.
The relative dispersal probability is given by exp(-d * value),
where d is the Euclidean distance between the origin and
destination patch.
Examples
# these are equivalent
disp <- dispersal(3)
disp <- d(3)
is.dispersal(disp)