Can't set limits with coord_trans

Question

I have some data that show a geometric relationship, but have outliers. For example:

x = seq(0.1, 1, 0.01)
dat = data.frame(x=x, y=10^x)
dat[50:60, 2] = 10

         


        

Answer 1

This may be a slightly simpler work-around:

library(ggplot2)

x = seq(0.1, 1, 0.01)
dat = data.frame(x=x, y=10^x)
dat[50:60, 2] = 10

plot_1 = ggplot(dat, aes(x=x, y=y)) +
         geom_line() +
         coord_cartesian(ylim=c(2, 8)) +
         scale_y_log10(breaks=c(2, 4, 6, 8), labels=c("2", "4", "6", "8"))

png("plot_1.png")
print(plot_1)
dev.off()

Answer 2

I had the same issue and struggled to solve it until looking more closely at ?coord_trans (in v1.0.0 of ggplot2):

Usage

coord_trans(xtrans = "identity", ytrans = "identity", limx = NULL, limy = NULL)

So you can set the transformations and the limits at the same time, like this:

ggplot(dat, aes(x=x, y=y)) + geom_line() +
  coord_trans(ytrans="log10", limy=c(2,8))