mrip - 5 months ago 49

R Question

I have a plot of a bunch of values between -1 and 1. Let's say it looks like this:

`data <- data.frame(x=1:20,y=runif(20)*2-1)`

p <- ggplot(data=data,aes(x=x,y=y)) + geom_line() + scale_y_continuous(breaks=seq(-1,1,0.5),limits=c(-1,1))

p

What I want is for the horizontal line with y=0, to be thicker than all the other gridlines. Is there a simple way to do this?

Answer

You can add a line at y = 0 via `geom_hline`

. Put this layer before `geom_line`

so it is behind the rest of the plot.

```
ggplot(data=data,aes(x=x,y=y)) +
geom_hline(yintercept = 0, color = "white", size = 2) +
geom_line() +
scale_y_continuous(breaks=seq(-1,1,0.5),limits=c(-1,1))
```