I would like to position the corresponding value labels in a geom_col
stacked barchart in the middle of each bar segment.
However, my naive attempt fails.
library(ggplot2) # Version: ggplot2 2.2
dta <- data.frame(group = c("A","A","A",
"B","B","B"),
sector = c("x","y","z",
"x","y","z"),
value = c(10,20,70,
30,20,50))
ggplot(data = dta) +
geom_col(aes(x = group, y = value, fill = sector)) +
geom_text(position="stack",
aes(x = group, y = value, label = value))
Obviously, setting y=value/2
for geom_text
does not help, either. Besides, the text is positioned in the wrong order (reversed).
Any (elegant) ideas how to solve this?
You need to have a variable mapped to an aesthetic to represent the groups in geom_text
. For you, this is your "sector" variable. You can use it with the group
aesthetic in geom_text
.
Then use position_stack
with vjust
to center the labels.
ggplot(data = dta) +
geom_col(aes(x = group, y = value, fill = sector)) +
geom_text(aes(x = group, y = value, label = value, group = sector),
position = position_stack(vjust = .5))
You could save some typing by setting your aesthetics globally. Then fill
would be used as the grouping variable for geom_text
and you can skip group
.
ggplot(data = dta, aes(x = group, y = value, fill = sector)) +
geom_col() +
geom_text(aes(label = value),
position = position_stack(vjust = .5))