| image.asc {adehabitat} | R Documentation |
These functions display a raster matrix of class asc.
## S3 method for class 'asc': image(x, col = gray((240:1)/256), clfac = NULL, ...) ## S3 method for class 'asc': contour(x, ...) ## S3 method for class 'asc': persp(x, ...) ## S3 method for class 'asc': plot(x, ...)
x |
a matrix of class asc |
col |
for maps of type "numeric", the colors to be used
(see help(par)) |
clfac |
for maps of type "factor", a character vector giving
the names of colors for each level of the factor (see
help(colasc)) |
... |
additional arguments to be passed to the generic
function image, persp, contour, and
filled.contour (but see below) |
The function plot.asc uses the function
filled.contour. The output produced by filled.contour is
actually a combination of two plots; one is the filled contour and one
is the legend. Two separate coordinate systems are set up for these
two plots, but they are only used internally - once the function has
returned these coordinate systems are lost. If you want to annotate
the main contour plot, for example to add points, you can specify
graphics commands in the plot.axes argument of the function
filled.contour (this argument is to be passed to the function
plot.asc).
An example is given below.
Clement Calenge clement.calenge@oncfs.gouv.fr
image, contour,
persp, filled.contour,
asc
data(puechabon)
# Case of a continuous variable: the elevation
my.map <- getkasc(puechabon$kasc, "Elevation")
image(my.map, main = "Elevation in Puechabon")
contour(my.map, add = TRUE)
# use of the function plot.asc: adding points on the map
plot(my.map, plot.axes = {points(puechabon$locs[,c("X","Y")])},
main = "Elevation")
# Case of a factor: the aspect
asp <- getkasc(puechabon$kasc, "Aspect")
cl <- colasc(asp, NorthEast = "blue", SouthEast = "red",
SouthWest = "orange", NorthWest = "green")
## graphical display
image(asp, clfac = cl, main = "Aspect", xlab = "Lambert X",
ylab = "Lambert Y")
legend(706500, 3162000, legend = levels(asp), fill = cl,
cex = 0.7)
opar<-par(mar = c(0,0,3,0), bg = "slategray")
persp(my.map, scale = FALSE, box = FALSE, border = NA, shade = 0.75,
col = "darkolivegreen3", expand = 2, theta = -60, phi = 30,
main = "The topography of Puechabon")
par(opar)