How do I plot a graph by based on 3 groups in ggplot?-CodePudding

gfg_data <- data.frame(year = c(2019, 2019, 2019, 2020, 2020, 2020, 2019, 2019, 2019, 2020, 2020, 2020),
                   city = c('Paris', 'Paris', 'Paris', 'Paris', 'Paris', 'Paris', 'Baku', 'Baku', 'Baku', 'Baku', 'Baku', 'Baku'),
                   rank = c('1-3', '1-3', '1-3', '4-6', '4-6', '4-6', '1-3', '1-3', '1-3', '4-6', '4-6', '4-6'),
                   Timings = c(5, 6, 4, 2, 3, 4, 11, 13, 15, 14, 17, 12),
                   Laps = c(1,2,3,1,2,3,1,2,3,1,2,3))

I would like to plot this data with laps on the x-axis and Timings on the y-axis. I'd like to use geom_line() and group the graph by city, rank, and year. So, I should have a line for 2019/Paris/1-3, 2019/Paris/4-6, 2020/Paris/1-3, 2020/Paris/4-6, etc. I'm unsure how I'd be able to do this using ggplot. Any help would be appreciated!

CodePudding user response：

From your description, it sounds like you need to combine year, city, and rank into a new variable.

library(tidyverse)
df <- data.frame(year = c(2019, 2019, 2019, 2020, 2020, 2020, 2019, 2019, 2019, 2020, 2020, 2020),
                       city = c('Paris', 'Paris', 'Paris', 'Paris', 'Paris', 'Paris', 'Baku', 'Baku', 'Baku', 'Baku', 'Baku', 'Baku'),
                       rank = c('1-3', '1-3', '1-3', '4-6', '4-6', '4-6', '1-3', '1-3', '1-3', '4-6', '4-6', '4-6'),
                       Timings = c(5, 6, 4, 2, 3, 4, 11, 13, 15, 14, 17, 12),
                       Laps = c(1,2,3,1,2,3,1,2,3,1,2,3)) %>%
  mutate(value = paste(year, city, rank))

ggplot(df, aes(x = Laps, y = Timings, col = value))  
  geom_point()  
  geom_line()

CodePudding user response：

For an interesting approach (though I would recommend you use whichever answer you find most straightforward), using interaction would allow grouping by those three variables without modifying the data sent to the ggplot function:

ggplot(df, aes(x = Laps, y = Timings, col = interaction(year, city, rank, sep = " ")))  
  geom_point()  
  geom_line()  
  scale_colour_discrete("Cohort")

This is little more than a "purist's" approach to ggplot - aiming to let the plotting functions do most of the work on a tidy dataset! Included here for interest.

Slight edit - you don't need to reformat labels if you use sep = " " in interaction call