I have two columns in a data.frame, that should have levels sorted in the same order, but I don't know how to do it in a straightforward manner.
Here's the situation:
library(ggplot2)
library(dplyr)
library(magrittr)
set.seed(1)
df1 <- data.frame(rating = sample(c("GOOD","BAD","AVERAGE"),10,T),
div = sample(c("A","B","C"),10,T),
n = sample(100,10,T))
# I'm adding a label column that I use for plotting purposes
df1 <- df1 %>% group_by(rating) %>% mutate(label = paste0(rating," (",sum(n),")")) %>% ungroup
# # A tibble: 10 x 4
# rating div n label
# <fctr> <fctr> <int> <chr>
# 1 BAD C 48 BAD (220)
# 2 BAD B 87 BAD (220)
# 3 BAD C 44 BAD (220)
# 4 GOOD B 25 GOOD (77)
# 5 AVERAGE B 8 AVERAGE (117)
# 6 AVERAGE C 10 AVERAGE (117)
# 7 AVERAGE A 32 AVERAGE (117)
# 8 GOOD B 52 GOOD (77)
# 9 AVERAGE C 67 AVERAGE (117)
# 10 BAD C 41 BAD (220)
# rating levels are sorted
df1$rating <- factor(df1$rating,c("BAD","AVERAGE","GOOD"))
ggplot(df1,aes(x=rating,y=n,fill=div)) + geom_col() # plots in the order I want
ggplot(df1,aes(x=label,y=n,fill=div)) + geom_col() # doesn't because levels aren't sorted
How do I manage to copy the factor order from one column to another ? I can make it work this way but I think it's really awkward:
lvls <- df1 %>% select(rating,label) %>% unique %>% arrange(rating) %>% extract2("label")
df1$label <- factor(df1$label,lvls)
ggplot(df1,aes(x=label,y=n,fill=div)) + geom_col()
Once you have set the levels of rating, you can use forcats to set the levels of label by the order of rating like this...
library(forcats)
df1 <- df1 %>% group_by(rating) %>%
mutate(label=paste0(rating," (",sum(n),")")) %>%
ungroup %>%
arrange(rating) %>% #sort by rating
mutate(label=fct_inorder(label)) #set levels by order in which they appear
Or you can use forcats::fct_reorder to do the same thing...
df1$label <- fct_reorder(df1$label, as.numeric(df1$rating))
The plot then has the bars in the right order.