Geom_point : when using color and alpha : how to delete the alpha legend in ggplot?

Question

I have this df that is visualized as followed:

df = data.frame(x = -10:11,
                y = seq(-5,5.5,by=0.5),
                z = rep(c(1,2),11) )

df

ggplot(df)+aes(x=x,y=y,color=factor(z),alpha=z)+
  geom_point()+
  geom_hline(yintercept=0)+
  geom_vline(xintercept = 0)+
  theme_blank()

The output:

I checked all similar questions but nothing has worked out to remove the alpha legend. Thanks.

Check the most recent answer - [Remove extra legends in ggplot2](https://stackoverflow.com/questions/11714951/remove-extra-legends-in-ggplot2) — margusl, Jan 20 '23 at 13:46

score 3 · Accepted Answer · answered Jan 20 '23 at 13:46

You could add in alpha in aesthetics and use guides to remove it like this:

df = data.frame(x = -10:11,
                y = seq(-5,5.5,by=0.5),
                z = rep(c(1,2),11) )
library(ggplot2)

ggplot(df)+aes(x=x,y=y,color=factor(z), alpha=z)+
  geom_point()+
  geom_hline(yintercept=0)+
  geom_vline(xintercept = 0) +
  guides(alpha = "none")

^{Created on 2023-01-20 with reprex v2.0.2}

Geom_point : when using color and alpha : how to delete the alpha legend in ggplot?

1 Answers1