geom_area position_stack order appears to have changed

[ptoche]

The default order of the data in geom_area() has changed. The order is no longer the order shown in the manual https://ggplot2.tidyverse.org/reference/position_stack.html

Was that intended? Is it documented?

series <- data.frame(
    time = c(rep(1, 4),rep(2, 4), rep(3, 4), rep(4, 4)),
    type = rep(c('a', 'b', 'c', 'd'), 4),
    value = rpois(16, 10)
)
library(ggplot2)
ggplot(series, aes(time, value)) +
    geom_area(aes(fill = type))

ggplot(series, aes(time, value)) + 
    geom_area(aes(fill = type), position = position_stack(reverse = TRUE))

Created on 2018-07-26 by the reprex package (v0.2.0).

Compare the above with the relevant part of the manual:

# Stacking is also useful for time series
series <- data.frame(
  time = c(rep(1, 4),rep(2, 4), rep(3, 4), rep(4, 4)),
  type = rep(c('a', 'b', 'c', 'd'), 4),
  value = rpois(16, 10)
) 
ggplot(series, aes(time, value)) +
  geom_area(aes(fill = type))

https://ggplot2.tidyverse.org/reference/position_stack-5.png

[ptoche]

An example from plots I made a couple of years ago.

Before:

After:

[karawoo]

It looks the same in the manual to me?

I do think the stack order changed at some point but it was a while ago in 2.2.0.

[ptoche]

@karawoo, You're probably right. My plots are from February 2015, so this may well be an old change.

The example from the manual confused me because I got a plot that looked quite different and assumed it was a common cause. The real reason is that the data used in the example is random. It might be useful to set a seed before the data is created to make it clearer, e.g.

set.seed(1)
series <- data.frame(
    time = c(rep(1, 4),rep(2, 4), rep(3, 4), rep(4, 4)),
    type = rep(c('a', 'b', 'c', 'd'), 4),
    value = rpois(16, 10)
)
ggplot(series, aes(time, value)) +
    geom_area(aes(fill = type))

[lock]

This old issue has been automatically locked. If you believe you have found a related problem, please file a new issue (with reprex) and link to this issue. https://reprex.tidyverse.org/