ggplot2 pie and donut chart on same plot

Question

I am trying to replicate this with R ggplot. I have exactly the same data:

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Answer 1

I find it easier to work in rectangular coordinates first, and when that is correct, then switch to polar coordinates. The x coordinate becomes radius in polar. So, in rectangular coordinates, the inside plot goes from zero to a number, like 3, and the outer band goes from 3 to 4.

For example

ggplot(browsers) + 
  geom_rect(aes(fill=version, ymax=ymax, ymin=ymin, xmax=4, xmin=3)) +
  geom_rect(aes(fill=browser, ymax=ymax, ymin=ymin, xmax=3, xmin=0)) +
  xlim(c(0, 4)) + 
  theme(aspect.ratio=1) 

Then, when you switch to polar, you get something like what you are looking for.

ggplot(browsers) + 
  geom_rect(aes(fill=version, ymax=ymax, ymin=ymin, xmax=4, xmin=3)) +
  geom_rect(aes(fill=browser, ymax=ymax, ymin=ymin, xmax=3, xmin=0)) +
  xlim(c(0, 4)) + 
  theme(aspect.ratio=1) +
  coord_polar(theta="y")  

This is a start, but may need to fine tune the dependency on y (or angle) and also work out the labeling / legend / coloring... By using rect for both the inner and outer rings, that should simplify adjusting the coloring. Also, it can be useful to use the reshape2::melt function to reorganize the data so then legend comes out correct by using group (or color).