NNCH.area {adehabitat} | R Documentation |
NNCH.area
calculates the area of the homerange for different
isopleth levels.
NNCH.k.area
for Fixed k LoCoH, computes a data frame containing
the area of the generated homerange vs the value of k
used.
NNCH.r.area
for Fixed r LoCoH, computes a data frame containing
the area of the generated homerange vs the value of r
used.
NNCH.a.area
for Adaptive LoCoH, computes a data frame containing
the area of the generated homerange vs the value of a
used.
NNCH.n.area
computes a data frame containing the area of the
generated homerange vs the variable referenced by n
. Called by
NNCH.k.area
, NNCH.r.area
, and NNCH.a.area
.
NNCH.der.n.area
computes a data frame containing the derivative
area of the generated homerange vs the variable referenced by n
.
Called by NNCH.der.k.area
, NNCH.der.r.area
, and
NNCH.der.a.area
.
NNCH.der.k.area
for Fixed k LoCoH, computes a data frame
containing the derivative of the area of the generated homerange vs the
value of k
used.
NNCH.der.r.area
for Fixed r LoCoH, computes a data frame
containing the derivative of the area of the generated homerange vs the
value of r
used.
NNCH.der.a.area
for Adaptive LoCoH, computes a data frame
containing the derivative of the area of the generated homerange vs the
value of a
used.
plot.narea
plots the data frames generated by the above functions
NNCH.area(x, percent = rev(seq(10, 100, by = 10)), id = NULL, k = NULL, r = NULL, a = NULL, plotit = TRUE) NNCH.k.area(x, ...) NNCH.a.area(x, ...) NNCH.r.area(x, ...) NNCH.der.k.area(x, ...) NNCH.der.a.area(x, ...) NNCH.der.r.area(x, ...) NNCH.n.area(x, n, percent = c(100,50), id = NULL, k = NULL, r = NULL, a = NULL) NNCH.der.n.area(x, n, ...) ## S3 method for class 'narea': plot(x, ...)
x |
a home range generated using the NNCH() method |
n |
the variable to graph area against; either k , r ,
or a |
percent |
the isopleths for which to calculate the area of the home range |
id |
character string specifying a subset of x |
k,r,a |
numeric values specifying a subset of x |
plotit |
logical. Whether the plot should be drawn. |
... |
additional arguments to be passed to the functions |
NNCH.n.area
and NNCH.der.n.area
return a data frame of
class narea
.
NNCH.area
returns a data frame of class hrsize
.
These functions are useful for determining critical values of
k
, r
, and a
. Big jumps in the the area indicate
that a new chunk of data has been included. Good values of k
,
r
, and a
, usually occur before or after a large jump.
Scott Fortmann-Roe scottfr@gmail.com
Clement Calenge clement.calenge@oncfs.gouv.fr
Getz, W.M. & Wilmers, C.C. (2004). A local nearest-neighbor convex-hull construction of home ranges and utilization distributions. Ecography, in press.
NNCH
for further information about the NNCH
method
## Not run: data(chamois) xy <- chamois$locs ## Try a number of neighbours between 6 and 18 (nn <- NNCH(xy, k = seq(6, 18, by=3))) (i <- NNCH.k.area(nn, percent=100)) plot(i) (i <- NNCH.der.k.area(nn, percent=100)) plot(i) ## Try a number of neighbours between 10 and 15 (nn <- NNCH(xy, k = 10:15)) opar <- par(mfrow=c(1,2)) (i <- NNCH.k.area(nn, percent=100)) plot(i) (i <- NNCH.der.k.area(nn, percent=100)) plot(i) par(opar) ## 12 neighbours seem to be a good choice nn <- NNCH(xy, k = 12) plot(nn) ## End(Not run)