So I am creating density plot for Sepal.Length for two species of the iris-dataset. The graph looks like this:
As you can see, I added two measures of central tendency to the graph (Median and Mean). However, right now they are colored depending on the measure (i.e., Median = black, Mean = grey).
I want to change the colors so that mean and median for Setosa/Versicolor have the same color. Furthermore, I want to add a legend indicating color and linetype for mean/median of setosa/versicolor. So in the end I would have a legend with four parts: Median Setosa, Mean Setosa, Median Versicolor, Mean Versiocolor.
Does anyone know how to do this? Please see code for reproduction below:
library(ggplot2)
library(tidyverse)
iris <- iris %>%
filter(Species == c("setosa", "versicolor"))
temp <- iris %>%
group_by(Species) %>%
dplyr::summarize(Mean = mean(Sepal.Length, na.rm=TRUE))
temp_2 <- iris %>%
group_by(Species) %>%
dplyr::summarize(Median = median(Sepal.Length, na.rm=TRUE))
ggplot(iris, aes(x = Sepal.Length, fill = factor(Species))) +
geom_density(alpha = 0.5) +
theme_minimal() +
geom_vline(data=temp, aes(xintercept=Mean, color="Mean"),
linetype="dotted",
lwd=1) +
geom_vline(data=temp_2, aes(xintercept=Median, color="Median"),
linetype="dashed",
lwd=1) +
scale_color_manual(name = "Statistics", values = c(Median = "black", Mean = "grey50")) +
labs(title = "Distribution of Sepal.Length",
x = "Sepal.Length",
y = "Density",
fill = "Species")
This is relatively complex. You would need to map the linetype and color of the lines to the interaction of Species
and a string denoting median or mean, than specify manual scales appropriately:
ggplot(iris, aes(x = Sepal.Length, fill = factor(Species))) +
geom_density(alpha = 0.5) +
theme_minimal() +
geom_vline(data=temp, aes(xintercept=Mean,
color = interaction(Species, 'Mean'),
linetype = interaction(Species, 'Mean')),
lwd = 1, key_glyph = draw_key_path) +
geom_vline(data=temp_2, aes(xintercept=Median,
color = interaction(Species, 'Median'),
linetype = interaction(Species, 'Median')),
lwd=1, key_glyph = draw_key_path) +
scale_linetype_manual(values = c(setosa.Mean = 'dotted',
setosa.Median = 'dashed',
versicolor.Mean = 'dotted',
versicolor.Median = 'dashed'),
name = 'Averages') +
scale_color_manual(values = c(setosa.Mean = "#F8766D",
setosa.Median = "#F8766D",
versicolor.Mean = "#00BFC4",
versicolor.Median = "#00BFC4"),
name = 'Averages') +
labs(title = "Distribution of Sepal.Length",
x = "Sepal.Length",
y = "Density",
fill = "Species") +
theme(legend.key.width = unit(15, 'mm'))