r - Showing total (sum) values each group on the top of stacked bar chart in ggplot2 -

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• draw sum value above stacked bar in ggplot2 1 answer

i used code make following stacked bar chart:

library(ggplot2) library(dplyr)  year      <- c(rep(c("2006", "2007", "2008", "2009"), each = 4)) category  <- c(rep(c("a", "b", "c", "d"), times = 4)) frequency <- c(168, 259, 226, 340, 216, 431, 319, 368, 423, 645, 234, 685, 166, 467, 274, 251) data      <- data.frame(year, category, frequency)  data2 <-data%>%   group_by(year, category)%>%     summarise(sum_grp = sum(frequency))  data3 <-transform(data2, pos = ave(frequency, year, fun = cumsum) - frequency / 2)  ggplot(data3, aes(year, frequency, group=category,fill = category))+   geom_bar(stat="identity")+   geom_text(aes(label = frequency,y=pos), size = 3)  

now, add sum of each group on top each bar not have idea how.

could me please?

thanks lot!!!!!

if wanted avoid making 3rd summary dataset, use stat_summary.

ggplot(data3, aes(year, frequency, group = category, fill = category))+     geom_bar(stat="identity")+     geom_text(aes(label = frequency,y=pos), size = 3)  +     stat_summary(fun.y = sum, aes(label = ..y.., group = year), geom = "text") 

use vjust move labels more if needed. found vjust = -.2 seemed pretty good.