Break label to include [min, max] of continuous splitvar rather than breakpoint only

[leombastos]

Hello.

I was trying to change the break label layout from showing only a numerical splitvar breakpoint to showing the splitvar range of values.

For ex., assuming a tree is fit and only one variable comes out in the final model, and this variable ranges from 0 to 60, and the model finds a breakpoint at 30.

Instead of showing break labels of "<30" and ">=30", I wish it would show break labels of "[0,30)" and "[30,60]".

Any chance this can be implemented with the current version of the package?

I gave it a try with add_vars, but gave up after spending some time.

Thanks!

[martin-borkovec]

Do you need it for just a single instance?
If so, the easiest way would probably be to just adjust the ggplot data like this:

library(ggparty)
#> Loading required package: ggplot2
#> Loading required package: partykit
#> Loading required package: grid
#> Loading required package: libcoin
#> Loading required package: mvtnorm
data("WeatherPlay", package = "partykit")
sp_o <- partysplit(1L, index = 1:3)
sp_h <- partysplit(3L, breaks = 75)
sp_w <- partysplit(4L, index = 1:2)
pn <- partynode(1L, split = sp_o, kids = list(
  partynode(2L, split = sp_h, kids = list(
    partynode(3L, info = "yes"),
    partynode(4L, info = "no"))),
  partynode(5L, info = "yes"),
  partynode(6L, split = sp_w, kids = list(
    partynode(7L, info = "yes"),
    partynode(8L, info = "no")))))
py <- party(pn, WeatherPlay)

ggpy <- ggparty(py)

ggpy$data$breaks_label[3] <- "(-Inf, 75]"
ggpy$data$breaks_label[4] <- "(75, Inf)"

ggpy +
geom_edge() +
  geom_edge_label() +
  geom_node_label(aes(label = splitvar),
                  ids = "inner") +
  geom_node_label(aes(label = info),
                  ids = "terminal")

^{Created on 2021-04-26 by the reprex package (v0.3.0)}

If you want to automate it for every plot, it will be a bit more tricky, but should be possible. Let me know.