R: Two columns and trying to make a density or boxplot. How do I stack them

Question

I have a dataframe that essentially looks like the following

score1   score2
1        1
2        2
3        3
4        4
5        5

They represent two different groups and I am trying to create a boxplot to compare them side by side. Is there a) a way of generating a boxplot or density plot with this data or b) a way of stacking them on top of each other to generate a dataframe that can be used to make such a plot? Here is the dataframe:

score1 <- c(1,2,3,4,5)
score2 <- c(1,2,3,4,5)
df <- data.frame(score1, score2)

Answer 1

Here's a tidyverse approach. Make the score labels and values into separate columns with pivot_longer . Then overlay or facet plots for comparison.

Overlay

library(tidyverse)

df %>% 
  pivot_longer(everything()) %>% 
  ggplot(aes(value, color = name)) +
  geom_density() # changed score2 to c(1,2,3,4,8) to show differences

Facet

df %>% 
  pivot_longer(everything()) %>% 
  ggplot(aes(value)) +
  geom_density() +
  facet_wrap(~name)

Answer 2

You can use the stack() function

boxplot(values~ind, stack(df))