Display last values in a multi-line chart as a label

[jynusmac]

Having this dataframe,

ggp <- data.frame(
  stringsAsFactors = FALSE,
  Month = c("01-2021", "02-2021", "03-2021", "04-2021"),
  Eur = c(4666395L, 6710095L, 8426865L, 7365811L),
  Tons = c(7677L, 11092L, 13930L, 11709L)
)

and making a multi line chart

ggplot(ggp, aes(Month)) +      
  geom_line(aes(y = Eur), colour = "red", group = "Eur") +
  geom_line(aes(y = Tons), colour = "blue", group = "Tons")

How can I make the graph show the last two values of each category as label? i.e. the last value of Eur (7365811) and Tons (11709). Any idea?

Thanks in advance

[nirgrahamuk]

ggp <- data.frame(
  stringsAsFactors = FALSE,
  Month = c("01-2021", "02-2021", "03-2021", "04-2021"),
  Eur = c(4666395L, 6710095L, 8426865L, 7365811L),
  Tons = c(7677L, 11092L, 13930L, 11709L)
)

last_df <- slice_tail(ggp,n=1) %>% pivot_longer(cols = -Month)

ggplot(ggp, aes(Month)) +      
  geom_line(aes(y = Eur), colour = "red", group = "Eur") +
  geom_line(aes(y = Tons), colour = "blue", group = "Tons")+
  geom_label(data=last_df,mapping = aes(y=value,label=value),
             nudge_x = .1)

[jynusmac]

Great. Many thanks nirgrahamuk. Can the box be removed?

[nirgrahamuk]

@nirgrahamuk

geom_label

use geom_text instead.

[jynusmac]

Great, thanks again, it's ok.

[jynusmac]

If I do this

ggpLong <- ggp %>% pivot_longer(cols = Eur:Tons, names_to = "Category", values_to = "Value")

to have the legend and then

ggplot(ggpLong, aes(x = Month, y = Value, color = Category, group = Category)) + geom_line()  +
  geom_label(data=last_df,mapping = aes(y=value,label=value), nudge_x = .1)

I get this error

Error in FUN(X[[i]], ...) : object 'Category' not found

[nirgrahamuk]

I would guess that last_df doesn't have the Category variable