Henk Henk - 3 months ago 15
R Question

ggplot color legend shape mixes alphanumeric and shape

The inclusion of ggrepel in a ggplot leads to a funny shape in the legend:

enter image description here.

Q: How do I replace this with a normal shape?

Sample code:

data(mtcars)
library(ggplot2)
library(ggrepel)

ggplot(mtcars, aes(x = mpg, y = wt, color = factor(vs), size = factor(cyl))) +
geom_point() +
geom_text_repel(aes(label = rownames(mtcars)), size = 5)


sessionInfo:

R version 3.2.3 (2015-12-10)
Platform: x86_64-pc-linux-gnu (64-bit)
Running under: Ubuntu 16.04.1 LTS

locale:
[1] LC_CTYPE=en_US.UTF-8 LC_NUMERIC=C LC_TIME=nl_NL.UTF-8 LC_COLLATE=en_US.UTF-8 LC_MONETARY=nl_NL.UTF-8 LC_MESSAGES=en_US.UTF-8 LC_PAPER=nl_NL.UTF-8
[8] LC_NAME=C LC_ADDRESS=C LC_TELEPHONE=C LC_MEASUREMENT=nl_NL.UTF-8 LC_IDENTIFICATION=C

attached base packages:
[1] stats graphics grDevices utils datasets methods base

other attached packages:
[1] magrittr_1.5 ggrepel_0.5 ggplot2_2.1.0.9000

loaded via a namespace (and not attached):
[1] labeling_0.3 colorspace_1.2-6 scales_0.4.0 assertthat_0.1 plyr_1.8.4 rsconnect_0.4.3 tools_3.2.3 gtable_0.2.0 tibble_1.1 Rcpp_0.12.6 grid_3.2.3 digest_0.6.10
[13] munsell_0.4.3

Answer

ggrepel has show.legend argument, so we need show.legend = FALSE as below:

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.

ggplot(mtcars, aes(x = mpg, y = wt, color = factor(vs), size = factor(cyl))) +
  geom_point() +
  geom_text_repel(aes(label = rownames(mtcars)), size = 5, show.legend = FALSE)

As a side note, prepare the data outside ggplot for clarity:

#fix the data
plotDat <- mtcars
plotDat$vs <- as.factor(plotDat$vs)
plotDat$cyl <- as.numeric(as.factor(plotDat$cyl))
plotDat$myLabel <- rownames(plotDat)

#then plot
ggplot(plotDat, aes(x = mpg, y = wt,
                    color = vs, size = cyl,
                    label = myLabel)) +
  geom_point() +
  geom_text_repel(size = 5, show.legend = FALSE)

enter image description here