ggplot2 / facet_wrap - shared labels for variables

Question

i have a problem i can't find a solution for.

I have a data set with 3 sample sites and different sample variables ("Bulk" and "Rhizosphere").

My code:

ggplot(data=dr_stats_all, aes(x=treatment, y=co2c, fill=type)) + 
  geom_bar(stat = "identity") + 
  facet_wrap(~ site  + type, nrow=1) 

This gives me six subplots with the sample site labels twice for "Bulk" and "Rhizosphere".

Is there a way to share the lables from the sample sites?

Answer 1

Would it not be easier to use only site to facet? You already use type to determine the fill, so adding a legend with the type (which is automatic) would suffice.

ggplot(data=dr_stats_all, aes(x=treatment, y=co2c, fill=type)) + 
geom_bar(stat = "identity") + 
facet_wrap(~ site, nrow=1)

If you really want to have nested facets, I also suggest taking a look at Henrik's suggestion