Plot labels at ends of lines

Question

I have the following data (temp.dat see end note for full data)

   Year State     Capex
1  2003   VIC  5.356415
2  2004   VIC  5.765232
3  2005   VIC  5.247276
4  2006   VIC  5.579882
5  2007   VIC  5.142464
...

and I can produce the following chart:

ggplot(temp.dat) + 
  geom_line(aes(x = Year, y = Capex, group = State, colour = State))

Instead of the legend, I'd like the labels to be

1. coloured the same as the series
2. to the right of the last data point for each series

I've noticed baptiste's comments in the answer in the following link, but when I try to adapt his code (geom_text(aes(label = State, colour = State, x = Inf, y = Capex), hjust = -1)) the text does not appear.

ggplot2 - annotate outside of plot

temp.dat <- structure(list(Year = c("2003", "2004", "2005", "2006", "2007", 
"2008", "2009", "2010", "2011", "2012", "2013", "2014", "2003", 
"2004", "2005", "2006", "2007", "2008", "2009", "2010", "2011", 
"2012", "2013", "2014", "2003", "2004", "2005", "2006", "2007", 
"2008", "2009", "2010", "2011", "2012", "2013", "2014", "2003", 
"2004", "2005", "2006", "2007", "2008", "2009", "2010", "2011", 
"2012", "2013", "2014"), State = structure(c(1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 
4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L), .Label = c("VIC", 
"NSW", "QLD", "WA"), class = "factor"), Capex = c(5.35641472365348, 
5.76523240652641, 5.24727577535625, 5.57988239709746, 5.14246402568366, 
4.96786288162828, 5.493190785287, 6.08500616799372, 6.5092228474591, 
7.03813541623157, 8.34736513875897, 9.04992300432169, 7.15830329914056, 
7.21247045701994, 7.81373928617117, 7.76610217197542, 7.9744994967006, 
7.93734452080786, 8.29289899132255, 7.85222269563982, 8.12683746325074, 
8.61903784301649, 9.7904327253813, 9.75021175267288, 8.2950673974226, 
6.6272705639724, 6.50170524635367, 6.15609626379471, 6.43799637295979, 
6.9869551384028, 8.36305663640294, 8.31382617231745, 8.65409824343971, 
9.70529678167458, 11.3102788081848, 11.8696420977237, 6.77937303542605, 
5.51242844820827, 5.35789621712839, 4.38699327451101, 4.4925792218211, 
4.29934654081527, 4.54639175257732, 4.70040615159951, 5.04056109514957, 
5.49921208937735, 5.96590909090909, 6.18700407463007)), class = "data.frame", row.names = c(NA, 
-48L), .Names = c("Year", "State", "Capex"))

Answer 1

To use Baptiste's idea, you need to turn off clipping. But when you do, you get garbage. In addition, you need to suppress the legend, and, for geom_text, select Capex for 2014, and increase the margin to give room for the labels. (Or you can adjust the hjust parameter to move the labels inside the plot panel.) Something like this:

library(ggplot2)
library(grid)

p = ggplot(temp.dat) + 
  geom_line(aes(x = Year, y = Capex, group = State, colour = State)) + 
  geom_text(data = subset(temp.dat, Year == "2014"), aes(label = State, colour = State, x = Inf, y = Capex), hjust = -.1) +
  scale_colour_discrete(guide = 'none')  +    
  theme(plot.margin = unit(c(1,3,1,1), "lines")) 

# Code to turn off clipping
gt <- ggplotGrob(p)
gt$layout$clip[gt$layout$name == "panel"] <- "off"
grid.draw(gt)

But, this is the sort of plot that is perfect for directlabels.

library(ggplot2)
library(directlabels)

ggplot(temp.dat, aes(x = Year, y = Capex, group = State, colour = State)) + 
  geom_line() +
  scale_colour_discrete(guide = 'none') +
  scale_x_discrete(expand=c(0, 1)) +
  geom_dl(aes(label = State), method = list(dl.combine("first.points", "last.points")), cex = 0.8) 

Edit To increase the space between the end point and the labels:

ggplot(temp.dat, aes(x = Year, y = Capex, group = State, colour = State)) + 
  geom_line() +
  scale_colour_discrete(guide = 'none') +
  scale_x_discrete(expand=c(0, 1)) +
  geom_dl(aes(label = State), method = list(dl.trans(x = x + 0.2), "last.points", cex = 0.8)) +
  geom_dl(aes(label = State), method = list(dl.trans(x = x - 0.2), "first.points", cex = 0.8)) 

Answer 2

A newer solution is to use ggrepel:

library(ggplot2)
library(ggrepel)
library(dplyr)

temp.dat %>%
  mutate(label = if_else(Year == max(Year), as.character(State), NA_character_)) %>%
  ggplot(aes(x = Year, y = Capex, group = State, colour = State)) + 
  geom_line() + 
  geom_label_repel(aes(label = label),
                  nudge_x = 1,
                  na.rm = TRUE)

Answer 3

This question is old but gold, and I provide another answer for weary ggplot folk.

This solution's principle can be applied quite generally.

Plot_df <- 
  temp.dat %>% mutate_if(is.factor, as.character) %>%  # Who has time for factors..
  mutate(Year = as.numeric(Year))

And now, we can subset our data

ggplot() + 
geom_line(data = Plot_df, aes(Year, Capex, color = State)) +
geom_text(data = Plot_df %>% filter(Year == last(Year)), aes(label = State, 
                                                           x = Year + 0.5, 
                                                           y = Capex, 
                                                           color = State)) + 
          guides(color = FALSE) + theme_bw() + 
          scale_x_continuous(breaks = scales::pretty_breaks(10))

The last pretty_breaks part is just to fix the axis below.

Answer 4

Not sure if it is the best way, but you could try the following (play a bit with xlim for correctly setting the limits):

library(dplyr)
lab <- tapply(temp.dat$Capex, temp.dat$State, last)
ggplot(temp.dat) + 
    geom_line(aes(x = Year, y = Capex, group = State, colour = State)) +
    scale_color_discrete(guide = FALSE) +
    geom_text(aes(label = names(lab), x = 12, colour = names(lab), y = c(lab), hjust = -.02))

Answer 5

I'd like to add a solution for cases when you have longer label names. In all of the solutions provided, the labels are within the plot canvas, but if you have longer names, they'll get cut off. Here's how I solved that issue:

library(tidyverse)

# Make the "State" variable have longer levels
temp.dat <- temp.dat %>% 
    mutate(State = paste0(State, '-a-long-string'))

ggplot(temp.dat, aes(x = Year, y = Capex, color = State, group = State)) + 
    geom_line() +
    # Add labels at the end of the line
    geom_text(data = filter(temp.dat, Year == max(Year)),
              aes(label = State),
              hjust = 0, nudge_x = 0.1) +
    # Allow labels to bleed past the canvas boundaries
    coord_cartesian(clip = 'off') +
    # Remove legend & adjust margins to give more space for labels
    # Remember, the margins are t-r-b-l
    theme(legend.position = 'none',
          plot.margin = margin(0.1, 2.6, 0.1, 0.1, "cm")) 

Answer 6

I came to this question looking to direct label a fitted line (e.g. loess()) at the last fitted point, not the last data point. I eventually worked out an approach to do this, largely based on tidyverse It should also work for linear regression with a few mods, so I leave it here for posterity.

library(tidyverse)

temp.dat$Year <- as.numeric(temp.dat$Year)
temp.dat$State <- as.character(temp.dat$State)

#example of loess for multiple models
#https://stackoverflow.com/a/55127487/4927395

models <- temp.dat %>%
  tidyr::nest(-State) %>%
  dplyr::mutate(
    # Perform loess calculation on each CpG group
    m = purrr::map(data, loess,
                   formula = Capex ~ Year, span = .75),
    # Retrieve the fitted values from each model
    fitted = purrr::map(m, `[[`, "fitted")
  )

# Apply fitted y's as a new column
results <- models %>%
  dplyr::select(-m) %>%
  tidyr::unnest()

#find final x values for each group
my_last_points <- results %>% group_by(State) %>% summarise(Year = max(Year, na.rm=TRUE))

#Join dataframe of predictions to group labels
my_last_points$pred_y <- left_join(my_last_points, results)

# Plot with loess line for each group
ggplot(results, aes(x = Year, y = Capex, group = State, colour = State)) +
  geom_line(alpha = I(7/10), color="grey", show.legend=F) +
  #stat_smooth(size=2, span=0.3, se=F, show_guide=F)
  geom_point(size=1) +
  geom_smooth(se=FALSE)+
  geom_text(data = my_last_points, aes(x=Year+0.5, y=pred_y$fitted, label = State))

Answer 7

You didn't emulate @Baptiste's solution 100%. You need to use annotation_custom and loop through all your Capex's:

library(ggplot2)
library(dplyr)
library(grid)

temp.dat <- structure(list(Year = c("2003", "2004", "2005", "2006", "2007", 
"2008", "2009", "2010", "2011", "2012", "2013", "2014", "2003", 
"2004", "2005", "2006", "2007", "2008", "2009", "2010", "2011", 
"2012", "2013", "2014", "2003", "2004", "2005", "2006", "2007", 
"2008", "2009", "2010", "2011", "2012", "2013", "2014", "2003", 
"2004", "2005", "2006", "2007", "2008", "2009", "2010", "2011", 
"2012", "2013", "2014"), State = structure(c(1L, 1L, 1L, 1L, 
1L, 1L, 1L, 1L, 1L, 1L, 1L, 1L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 2L, 
2L, 2L, 2L, 2L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 3L, 
4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L, 4L), .Label = c("VIC", 
"NSW", "QLD", "WA"), class = "factor"), Capex = c(5.35641472365348, 
5.76523240652641, 5.24727577535625, 5.57988239709746, 5.14246402568366, 
4.96786288162828, 5.493190785287, 6.08500616799372, 6.5092228474591, 
7.03813541623157, 8.34736513875897, 9.04992300432169, 7.15830329914056, 
7.21247045701994, 7.81373928617117, 7.76610217197542, 7.9744994967006, 
7.93734452080786, 8.29289899132255, 7.85222269563982, 8.12683746325074, 
8.61903784301649, 9.7904327253813, 9.75021175267288, 8.2950673974226, 
6.6272705639724, 6.50170524635367, 6.15609626379471, 6.43799637295979, 
6.9869551384028, 8.36305663640294, 8.31382617231745, 8.65409824343971, 
9.70529678167458, 11.3102788081848, 11.8696420977237, 6.77937303542605, 
5.51242844820827, 5.35789621712839, 4.38699327451101, 4.4925792218211, 
4.29934654081527, 4.54639175257732, 4.70040615159951, 5.04056109514957, 
5.49921208937735, 5.96590909090909, 6.18700407463007)), class = "data.frame", row.names = c(NA, 
-48L), .Names = c("Year", "State", "Capex"))

temp.dat$Year <- factor(temp.dat$Year)

color <- c("#8DD3C7", "#FFFFB3", "#BEBADA", "#FB8072")

gg <- ggplot(temp.dat) 
gg <- gg + geom_line(aes(x=Year, y=Capex, group=State, colour=State))
gg <- gg + scale_color_manual(values=color)
gg <- gg + labs(x=NULL)
gg <- gg + theme_bw()
gg <- gg + theme(legend.position="none")

states <- temp.dat %>% filter(Year==2014)

for (i in 1:nrow(states))  {
  print(states$Capex[i])
  print(states$Year[i])
  gg <- gg + annotation_custom(
    grob=textGrob(label=states$State[i], 
                    hjust=0, gp=gpar(cex=0.75, col=color[i])),
    ymin=states$Capex[i],
    ymax=states$Capex[i],
    xmin=states$Year[i],
    xmax=states$Year[i])
}    

gt <- ggplot_gtable(ggplot_build(gg))
gt$layout$clip[gt$layout$name == "panel"] <- "off"
grid.newpage()
grid.draw(gt)

(You'll want to change the yellow if you keep the white background.)