classif.ranger not working when target variable is not in the last column

[FlorianPargent]

use classif.ranger to predict "diabetes" in pid.task (this works)

lrn = makeLearner("classif.ranger")
holdout(lrn, pid.task)

however, when "diabetes" is not the last but the second last variable in the dataframe
resampling does not work

task = makeClassifTask(data = getTaskData(pid.task)[,c(2:9, 1)], target = "diabetes")
holdout(lrn, task)

[bhvieira]

Hmm, sometimes it even crashes RGui.exe for me. iris.task worked fine with Species as the first column, changing it to second crashed the execution.

[jakob-r]

Can you check running it for ranger directly? If this crashes (what I think will happen) I will contact @mnwright but until then I propose the workaround to simply put the target column in the last column via something like

data = getTaskData(.task, .subset, target.extra = TRUE)
ranger::ranger(formula = NULL, dependent.variable = tn, data = cbind(data$task, data$target), write.forest = TRUE, ...)

[berndbischl]

hi this really seems like a 100% ranger problem.
please reopen if you can confirm that this has anything to do with mlr.

[mnwright]

Fixed in ranger.

[berndbischl]

Fixed in ranger.

cool thx. mlr seems to work nicely as a "bug detector" for other packages :)