getMeanSD(xy)
maskarea(mask, sessnum = 1)
masklength(mask, sessnum = 1)
edist(xy1, xy2)
nedist(xy1, xy2, mask, inf = Inf, ...)
transition
getMeanSD
, a dataframe with columns `x' and `y' and two
rows, mean and SD.
For maskarea
, the summed area of mask cells in hectares (ha).
For masklength
, the summed length of mask cells in kilometers (km).
For edist
and nedist
, a matrix with dim = c(nrow(xy1), nrow(xy2)).getmeanSD
is used by make.mask
to standardize
mask coordinates.
For masklength
the input should be a linear mask from edist
computes the Euclidean distance between each point in xy1
and each point in xy2. (This duplicates the functionality of `rdist'
in package nedist
computes the non-Euclidean distance between each point
in xy1 and each point in xy2, in two dimensions. The calculation uses
mask
. By default, points within a 16-point
neighbourhood are considered `adjacent'. Distances are obtained by
Dijkstra's (1959) algorithm as least cost paths through the graph of
all points in the mask.
nedist
has some subtle options. If `mask' is missing then the
transition layer will be formed from `xy2'. If `mask' has a covariate
named `noneuc' then this will be used to weight distances. The ...argument of nedist
allows the user to vary arguments of
transition
(defaults transitionFunction =
mean and directions = 16). Be warned this can lead to unexpected
results! Point pairs that are completely separated receive the
distance +Inf unless a finite value is provided for the argument
`inf'. See
nedist
.