stat_summary fun.data

[bholt]

I'm confused about how stat_summary is supposed to work. The documentation claims that a data frame is passed as input, and it's expected to return a data frame. However, when I write my own and print the contents of the input parameter, I get just the y vector:

test <- function(y) { print(y) }
ggplot(...)+stat_summary(fun.data=test, geom="text")

This made more sense when I looked here: https://github.com/hadley/ggplot2/blob/master/R/stat-summary.r#L128 and saw that it was just passing df$y.

Am I missing something? What is the correct way to use fun.data?

Thanks.

[hadley]

I think the documentation is wrong - the function only gets a single vector, but it can return a data frame.

[bholt]

Okay thanks for the clarification. It would be more useful (for my use case) to receive the full data frame. But perhaps a new interface that doesn't break existing uses.