grouped barplot: order x-axis & keep constant bar width, in case of missing levels

Question

Here is my script (example inspired from here and using the reorder option from here):

library(ggplot2)
Animals <- read.table(
  header=TRUE, tex         


        

Answer 1

To achieve something like that I would adjust the data frame when working with ggplot. Add the missing categories with a value of zero.

Animals <- rbind(Animals, 
                 data.frame(Category = c("Improved", "Decline"), 
                            Reason = c("Hello", "Bla"), 
                            Species = c(0,0)
                            )
)