A kernel density estimate, useful for display the distribution of variables with underlying smoothness.
Usage
geom_density(
mapping = NULL,
data = NULL,
stat = "density",
position = "identity",
...,
na.rm = FALSE,
show.legend = NA,
inherit.aes = TRUE
)
stat_density(
mapping = NULL,
data = NULL,
geom = "area",
position = "stack",
...,
bw = "nrd0",
adjust = 1,
kernel = "gaussian",
trim = FALSE,
na.rm = FALSE,
show.legend = NA,
inherit.aes = TRUE
)
Arguments
- mapping
Set of aesthetic mappings created by
aes
oraes_
. If specified andinherit.aes = TRUE
(the default), it is combined with the default mapping at the top level of the plot. You must supplymapping
if there is no plot mapping.- data
The data to be displayed in this layer. There are three options:
If
NULL
, the default, the data is inherited from the plot data as specified in the call toggplot
.A
data.frame
, or other object, will override the plot data. All objects will be fortified to produce a data frame. Seefortify
for which variables will be created.A
function
will be called with a single argument, the plot data. The return value must be adata.frame.
, and will be used as the layer data.- position
Position adjustment, either as a string, or the result of a call to a position adjustment function.
- ...
other arguments passed on to
layer
. These are often aesthetics, used to set an aesthetic to a fixed value, likecolor = "red"
orsize = 3
. They may also be parameters to the paired geom/stat.- na.rm
If
FALSE
(the default), removes missing values with a warning. IfTRUE
silently removes missing values.- show.legend
logical. Should this layer be included in the legends?
NA
, the default, includes if any aesthetics are mapped.FALSE
never includes, andTRUE
always includes.- inherit.aes
If
FALSE
, overrides the default aesthetics, rather than combining with them. This is most useful for helper functions that define both data and aesthetics and shouldn't inherit behaviour from the default plot specification, e.g.borders
.- geom, stat
Use to override the default connection between
geom_density
andstat_density
.- bw
the smoothing bandwidth to be used, see
density
for details- adjust
adjustment of the bandwidth, see
density
for details- kernel
kernel used for density estimation, see
density
for details- trim
This parameter only matters if you are displaying multiple densities in one plot. If
FALSE
, the default, each density is computed on the full range of the data. IfTRUE
, each density is computed over the range of that group: this typically means the estimated x values will not line-up, and hence you won't be able to stack density values.
Aesthetics
geom_density
understands the following aesthetics (required aesthetics are in bold):
x
y
alpha
colour
fill
linetype
size
weight
Computed variables
- density
density estimate
- count
density * number of points - useful for stacked density plots
- scaled
density estimate, scaled to maximum of 1
See also
See geom_histogram
, geom_freqpoly
for
other methods of displaying continuous distribution.
See geom_violin
for a compact density display.
Examples
ggplot(diamonds, aes(carat)) +
geom_density()
ggplot(diamonds, aes(carat)) +
geom_density(adjust = 1/5)
ggplot(diamonds, aes(carat)) +
geom_density(adjust = 5)
ggplot(diamonds, aes(depth, colour = cut)) +
geom_density() +
xlim(55, 70)
#> Warning: Removed 45 rows containing non-finite values (stat_density).
ggplot(diamonds, aes(depth, fill = cut, colour = cut)) +
geom_density(alpha = 0.1) +
xlim(55, 70)
#> Warning: Removed 45 rows containing non-finite values (stat_density).
# \donttest{
# Stacked density plots: if you want to create a stacked density plot, you
# probably want to 'count' (density * n) variable instead of the default
# density
# Loses marginal densities
ggplot(diamonds, aes(carat, fill = cut)) +
geom_density(position = "stack")
# Preserves marginal densities
ggplot(diamonds, aes(carat, ..count.., fill = cut)) +
geom_density(position = "stack")
# You can use position="fill" to produce a conditional density estimate
ggplot(diamonds, aes(carat, ..count.., fill = cut)) +
geom_density(position = "fill")
# }