Superimpose a function.

Usage

stat_function(mapping = NULL, data = NULL, geom = "path", position = "identity", fun, n = 101, args = list(), na.rm = FALSE, show.legend = NA, inherit.aes = TRUE, ...)

Arguments

mapping
The aesthetic mapping, usually constructed with aes or aes_string. Only needs to be set at the layer level if you are overriding the plot defaults.
data
A layer specific dataset - only needed if you want to override the plot defaults.
geom
The geometric object to use display the data
position
The position adjustment to use for overlapping points on this layer
fun
function to use
n
number of points to interpolate along
args
list of additional arguments to pass to fun
na.rm
If FALSE (the default), removes missing values with a warning. If TRUE 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, and TRUE 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.
...
other arguments passed on to layer. This can include aesthetics whose values you want to set, not map. See layer for more details.

Description

Superimpose a function.

Aesthetics

stat_function understands the following aesthetics (required aesthetics are in bold):

  • y

Computed variables

x
x's along a grid

y
value of function evaluated at corresponding x

Examples

set.seed(1492) df <- data.frame( x = rnorm(100) ) x <- df$x base <- ggplot(df, aes(x)) + geom_density() base + stat_function(fun = dnorm, colour = "red")

base + stat_function(fun = dnorm, colour = "red", arg = list(mean = 3))

# Plot functions without data # Examples adapted from Kohske Takahashi # Specify range of x-axis ggplot(data.frame(x = c(0, 2)), aes(x)) + stat_function(fun = exp, geom = "line")

# Plot a normal curve ggplot(data.frame(x = c(-5, 5)), aes(x)) + stat_function(fun = dnorm)

# To specify a different mean or sd, use the args parameter to supply new values ggplot(data.frame(x = c(-5, 5)), aes(x)) + stat_function(fun = dnorm, args = list(mean = 2, sd = .5))

# Two functions on the same plot f <- ggplot(data.frame(x = c(0, 10)), aes(x)) f + stat_function(fun = sin, colour = "red") + stat_function(fun = cos, colour = "blue")

# Using a custom function test <- function(x) {x ^ 2 + x + 20} f + stat_function(fun = test)