R facet with geom_col?

Question

I have imported the below excel file into the RStudio

My goal is to display in a facet of 4 different barplots with x axis representing the categorical variable of algorithms, and y displays the percentages each time as they are counted already in columns Question_1,2,3,4. I use this simple R code to plot just one barplot

ggplot(data = R_Analysis_draft, mapping = aes(x = algorithms,y = Question_1)) +
     geom_col()

How can I display all 4 in the same facet since they all have the same categorical variable algorithms putting a header on top of each one different Question and using the percentages?

Answer 1

You can use

library(tidyverse)

df %>% 
  pivot_longer(-algorithms) %>% 
  ggplot(aes(x = algorithms, y = value, fill = name)) +
  geom_col()

or

df %>% 
  pivot_longer(-algorithms) %>% 
  ggplot(aes(x = algorithms, y = value, fill = name)) +
  geom_col(position = position_dodge())

For faceted plotting use

df %>% 
  pivot_longer(-algorithms) %>% 
  ggplot(aes(x = algorithms, y = value)) +
  geom_col(position = position_dodge()) + 
  facet_wrap(name~.)

Data

df = structure(list(algorithms = c("Alg_1", "Alg_2", "Alg_3", "Alg_4", 
"Alg_5"), Question_1 = c(51L, 43L, 48L, 48L, 54L), Question_2 = c(49L, 
35L, 53L, 39L, 63L), Question_3 = c(55L, 42L, 54L, 48L, 47L), 
    Question_4 = c(52L, 36L, 46L, 48L, 55L)), class = "data.frame", row.names = c(NA, 
-5L))