stat_density2d {ggplot2} | R Documentation |
Density estimation, 2D
stat_density2d(mapping=NULL, data=NULL, geom="density2d", position="identity", na.rm=FALSE, contour=TRUE, ...)
mapping |
mapping between variables and aesthetics generated by aes |
data |
dataset used in this layer, if not specified uses plot dataset |
geom |
geometric used by this layer |
position |
position adjustment used by this layer |
na.rm |
NULL |
contour |
NULL |
... |
ignored |
This page describes stat_density2d, see layer
and qplot
for how to create a complete plot from individual components.
A layer
The following aesthetics can be used with stat_density2d. Aesthetics are mapped to variables in the data with the aes
function: stat\_density2d(\code{aes}(x = var))
x
: x position (required)
y
: y position (required)
colour
: border colour
size
: size
group
: how observations are divided into different groups
Hadley Wickham, http://had.co.nz/
## Not run: m <- ggplot(movies, aes(x=rating, y=length)) + geom_point() + scale_y_continuous(limits=c(1, 500)) m + geom_density2d() dens <- MASS::kde2d(movies$rating, movies$length, n=100) densdf <- data.frame(expand.grid(rating = dens$x, length = dens$y), z=as.vector(dens$z)) m + geom_contour(aes(z=z), data=densdf) m + geom_density2d() + scale_y_log10() m + geom_density2d() + coord_trans(y="log10") m + stat_density2d(aes(fill = ..level..), geom="polygon") qplot(rating, length, data=movies, geom=c("point","density2d"), ylim=c(1, 500)) # If you map an aesthetic to a categorical variable, you will get a # set of contours for each value of that variable qplot(rating, length, data = movies, geom = "density2d", colour = factor(Comedy), ylim = c(0, 150)) qplot(rating, length, data = movies, geom = "density2d", colour = factor(Action), ylim = c(0, 150)) qplot(carat, price, data = diamonds, geom = "density2d", colour = cut) # Another example ------ d <- ggplot(diamonds, aes(carat, price)) + xlim(1,3) d + geom_point() + geom_density2d() # If we turn contouring off, we can use use geoms like tiles: d + stat_density2d(geom="tile", aes(fill = ..density..), contour = FALSE) last_plot() + scale_fill_gradient(limits=c(1e-5,8e-4)) # Or points: d + stat_density2d(geom="point", aes(size = ..density..), contour = FALSE) ## End(Not run)