2D scatter plot with kernel density estimation
Description
This function represents a two dimensional scatter plot of points distribution.
Densities' representation is based on the levelplot
graphic in lattice
(density's surface, filled with colors and/or contour lines).
Usage
1 2 3 
Arguments
dfxy 
a data frame used to produce the plot 
xax 
an integer (or a vector) indicating which column(s) of 
yax 
an integer (or a vector) indicating which column(s) of 
bandwidth 
bandwidth for density calculations which is passed in parameters in the 
gridsize 
grid dimension 
nrpoints 
number of points on the density image 
threshold 
a value between 0 and 1 to draw densities greater than this threshold. No density is visible whether it is equal to 1 
col 
a color or a colors vector to color densities 
contour 
a logical to draw contour lines 
region 
a logical to fill grid regions with 
nclass 
number of class for density 
facets 
a factor splitting the rows of 
plot 
a logical indicating if the graphics is displayed 
storeData 
a logical indicating if the data should be stored in
the returned object. If 
add 
a logical. If 
pos 
an integer indicating the position of the
environment where the data are stored, relative to the environment
where the function is called. Useful only if 
... 
additional graphical parameters (see

Details
Density calculation is made using the kde2d
function of the KernSmooth
package.
Value
An object of class ADEg
(subclass S2.density
) or ADEgS
(if add
is TRUE
and/or
if facets or vectors for xax
/yax
are used).
The result is displayed if plot
is TRUE
.
Author(s)
Alice JulienLaferriere, Aurelie Siberchicot aurelie.siberchicot@univlyon1.fr and Stephane Dray
See Also
S2.density
ADEg.S2
Examples
1 2 3 4 5  xx2 < c(rnorm(50000, 1, 1), rnorm(50000, 1, 1))
yy2 < c(rnorm(50000, 1, 0.5), rnorm(50000, 1, 0.5))
s.density(cbind(xx2, yy2), paxes.draw = TRUE, gridsize = c(200, 200), region = TRUE,
contour = TRUE, plabels.cex = 0, threshold = 0.05, nclass = 3,
col = colorRampPalette(c("lightgrey", "black"))(100))
