X轴堆叠条形图上的多列

Question

I'm beginner in R programming, exploring ggplot. I'm trying to plot stacked bar chart to show 3 years quarterly revenue for multiple countries. I'm using data from https://www.ibm.com/communities/analytics/watson-analytics-blog/sales-products-sample-data/

mydata <- read.csv("~/Downloads/WA_Sales_Products_2012-14.csv") 
library(dplyr)
qtrSales <- mydata %>%
group_by(mydata$Retailer.country, mydata$Year, mydata$Quarter) %>%
summarize(Rev=sum(Revenue)) %>%

qtrSales <- data.frame(qtrSales)
colnames(qtrSales) <- c("Country", "Year", "Qtr", "Revenue")

library(ggplot2)
ggplot() + geom_bar(aes(y=qtrSales$Revenue, x = qtrSales$Year, 
fill=qtrSales$Qtr), data=qtrSales, stat="identity")

above ggplot is giving me what I want is to have 3 bars for each year grouped together for each country. Can anyone advise how to achieve it?

Answer 1

Here I put Quarter instead of Year on x-axis, otherwise you would need to use facets.

colnames(mydata)[1] <- "Country"
library(ggplot2)
ggplot(mydata, aes(Quarter, Revenue, fill = Country)) +
    geom_bar(stat = "identity", position = "dodge") +
    scale_x_discrete(limits = unique(mydata$Quarter)) +
    theme(legend.position = "bottom") +
    guides(fill = guide_legend(nrow = 2))