ggplot2 barplot with total values split into two groups

Question

suppose I have a data frame:

df<-data.frame(specie=c('apple','banana','orange'),total=c(1000,500,850),fresh=c(NA,250,700),processed=c(NA,250,150))

Note that for Apple, only Total value is available. I would like to create a bar plot that show both fresh and processed values for each specie, and show only total value for the case of Apple where fresh and processed values are NAs.

I tried with the codes below, but didn't get the plot I want:

p<-df %>% ggplot(aes(x=total,y=specie))
p+geom_col()+geom_col(aes(x=fresh,fill="fresh"))+geom_col(aes(x=processed,fill="processed"))

Why total area exceeds fresh and processed?

Answer 1

You need to rework your data set in a way that your columns name became the modalities of a variable, and all the values are in the same columns.

df<-data.frame(specie=c('apple','banana','orange'),unknow=c(1000,NA,NA),fresh=c(NA,250,700),processed=c(NA,250,150))
df <- df %>% tidyr::pivot_longer(cols = c("unknow", "fresh", "processed"),names_to = "type")



ggplot2::ggplot() +
  ggplot2::geom_bar(data = df,
                    mapping = ggplot2::aes(x = specie,
                                           y = value,
                                           fill = type),
                    stat = "identity")