Continuous Horizontal geom_line in each region

Question

For the geom_line in the ggplot below, I would like to have a straight green line in each region as all the dimension in the region has the same value.

Is there an easy way to do this? I am using the following code.

p<- ggplot(df, aes(y=value, x=country, fill=category)) + 
  geom_bar(stat="identity", position ="dodge")+
  geom_line(aes(y=value, group = NA), col="darkgreen")+
  xlab("regions")+ylab("Categories")+
  theme_bw()+
  theme(legend.position = "right")+
  scale_fill_manual(" ", values = c("Ne" = "#00AFBB", "Np" = "#FC4E07", "Nt" ="#4E84C4", "Ns" ="#E7B800"))+
  theme(legend.title=element_blank())+
  theme(legend.spacing.x = unit(0.3, 'cm'))+
  scale_y_continuous(expand = c(0, 0), limits = c(0, 100),breaks = c(0,10,20,30,40,50,60,70,80,90,100))+
  scale_color_manual(name="", values = c("mean"="#3ADF00"), labels = c("Average"))

Additionally, how can I add the x-axis labels to be in two rows so the labels do not overlap each other?

Why do you have group set to NA for the line? Have you tried setting it to a dummy value? And why do you have two seemingly-similar `geom_line` calls? Beyond that, hard to do more than guess without a [reproducible example](https://stackoverflow.com/questions/5963269/how-to-make-a-great-r-reproducible-example) — camille, Aug 26 '19 at 16:52
Two geom_line was just a mistake, I will try to set the dummy value for the line. Thank you! — tropicalbath, Aug 26 '19 at 17:11
This is basically a [duplicate](https://stackoverflow.com/questions/41569793/adding-group-mean-lines-to-geom-bar-plot-and-including-in-legend). — Rui Barradas, Aug 26 '19 at 17:25

score 1 · Answer 1 · answered Aug 26 '19 at 17:38

The solution is to use geom_errorbar, like in this possible duplicate.

library(ggplot2)

p <- ggplot(new_africa, aes(x = Africa, y = value, fill = dimension)) + 
  geom_bar(stat = "identity", position = "dodge") +
  geom_errorbar(aes(ymax = groupMeans, ymin = groupMeans, colour = mean)) +
  scale_fill_manual(values = c(GEO = "#00AFBB", 
                               NC = "#FC4E07", 
                               RE ="#4E84C4",
                               SI = "#E7B800")) +
  scale_color_manual(name = "", 
                     values = "#3ADF00", 
                     labels = "Green Growth Index") +
  xlab("Region") + ylab("Dimensions of green growth")+
  theme_bw() +
  theme(legend.position = "right",
        legend.title = element_blank(),
        legend.spacing.x = unit(0.3, 'cm'))

p

Data preparation code.

This code uses the built in data set iris. I take advantage of its structure and change column names and factor values.

df1 <- iris
names(df1) <- c("GEO", "NC", "RE", "SI", "Africa")
df1$Africa <- c(rep("Eastern Africa", 50),
                rep("Middle Africa", 50),
                rep("Western Africa", 50))

new_africa <- reshape2::melt(df1, id.vars = "Africa")
names(new_africa)[2] <- "dimension"
new_africa$groupMeans <- ave(new_africa$value, new_africa$Africa, FUN = mean)
new_africa$mean <- "Mean"

Hi, thank you very much for the solution. Do you perhaps know the way to join the horizontal lines? Thank you once again! :) — tropicalbath, Aug 26 '19 at 18:41
@tropicalbath Glad it is usefull. And no, I din't know how to join the lines but it doesn't seem to be easy, the joining lines would go to an area with nothing plotted. — Rui Barradas, Aug 26 '19 at 18:51

Continuous Horizontal geom_line in each region

1 Answers1