ggplot2 barplot with total values split into two groups-CodePudding

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?

CodePudding user response：

So, you have three categories. These are overlaying the bars one on top of another. So ggplot draws the NA bars, then the fresh on top, then finally the processed ones. I imagine that you want stacked bars, that add up the total numbers. So, instead, you will want a longer dataframe with a column for fruit type and you don't need the totals. The you map fill onto the type as you plot. Like so:

df<-data.frame(specie=c('apple','banana','orange', 'banana','orange'),type = c(NA, "fresh", "fresh", "processed","processed"), num=c(1000, 250, 700,250,150))
df %>% ggplot(aes(x=num,y=specie, fill= type)) geom_col(position='stack')

CodePudding user response：

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")