Plotting axes in R

Question

I am supposed to plot the following function:

h <- function(x) 0.08-0.06*(1-exp((-x)/(1.5)))/((x)/(1.5))-0.3*((1-exp((-x)/(1.5)))/((x)/(1.5))-exp(-((x)/(1.5)))+0.6*((1-exp((-x)/(0.5)))/((x)/(0.5))-exp(-((x)/(0.5)))))

So I did:

plot(-1:24, h(-1:24), type="l")

and it would be for x-axes. But I do not know how to change it for y.

For x I want to draw it from -1 to 24 and for y from -0.5 to 0.2.

Can anybody help?

Answer 1

An issue with your function is that it is undefined at 0, so you get a single point at x == -1 followed by a gap until x == 1. You'll get a better plot with more points, e.g.

x <- seq(-1, 24, len=200)
plot(x, h(x), type = "l")

(which never evaluates it at exactly zero, so the gap doesn't appear).

If you still want to change the axis limits, use

x <- seq(-1, 24, len=200)
plot(x, h(x), type = "l", ylim = c(-0.5, 2))

Answer 2

With ggplot2 you can do:

library(ggplot2)
data = data.frame(x = -1:24)
ggplot(data, aes(x=x)) + stat_function(fun=h) + ylim(-0.5,2)

Or

data = data.frame(x = -1:24, y = h(-1:24))
ggplot(data, aes(x=x, y=y)) + geom_line() + ylim(-0.5,2)

But a solution with plot is probably easier as its a very simple thing, ggplot is kinda overkill i guess.