Get values and positions to label a ggplot histogram
Below code works well and it labels the barplot correctly, However, if I try geom_text
for a histogram I fail since geom_text
requires a y
-component and a histogram's y
component is not part of the original data.
Label an "ordinary" bar plot (geom_bar(stat = "identity"
) works well:
ggplot(csub, aes(x = Year, y = Anomaly10y, fill = pos)) +
geom_bar(stat = "identity", position = "identity") +
geom_text(aes(label = Anomaly10y,vjust=1.5))
My Problem: How to get the correct y
and label
(indicated by ?
) for geom_text
, to put labels on top of the histogram bars
ggplot(csub,aes(x = Anomaly10y)) +
geom_histogram()
geom_text(aes(label = ?, vjust = 1.5))
geom_text
requires x
, y
and labels
. However, y
and labels
are not in the original data, but generated by the geom_histogram
function. How can I extract the necessary data to position labels on a histogram?
geom_histogram()
is just a fancy wrapper to stat_bin
so you can all that yourself with the bars and text that you like. Here's an example
#sample data
set.seed(15)
csub<-data.frame(Anomaly10y = rpois(50,5))
And then we plot it with
ggplot(csub,aes(x=Anomaly10y)) +
stat_bin(binwidth=1) + ylim(c(0, 12)) +
stat_bin(binwidth=1, geom="text", aes(label=..count..), vjust=-1.5)
to get
Ok to make it aesthetically appealing here is the solution:
set.seed(15)
csub <- data.frame(Anomaly10y = rpois(50, 5))
Now Plot it
csub %>%
ggplot(aes(Anomaly10y)) +
geom_histogram(binwidth=1) +
stat_bin(binwidth=1, geom='text', color='white', aes(label=..count..),
position=position_stack(vjust = 0.5))
resultant plot will be