For example we have usual stacked bar plot:
ggplot(diamonds, aes(x=color, fill=cut))+geom_bar(position="fill")
And I want to make same plot but leave on it only one of "Cut" - types. For example "Ideal" (purple one). Thus, it should be something like histogram of fraction of the Ideal diamonds among all other diamonds having same color. Can I do this within ggplot?