[BUGZILLA #15696] Potential infinite loop in model.frame.tree

[MichaelChirico]

The model.frame method for tree objects includes this line:

while (deparse(oc[[1L]]) != "tree") oc <- eval(oc[[2L]])$call

if the tree object was constructed with a call including the package name (i.e.: tree::tree(...)), the above loop will never end.

Example:

First, successful example using plain "tree"

library(tree)
library(ISLR)
attach(Carseats)
High=ifelse(Sales<=8, "no", "Yes")
Carseats=data.frame(Carseats, High)
tree.carseats = tree(High~.-Sales, Carseats)
head(model.frame(tree.carseats))

Now, problem using "tree::tree"

bad.carseats = tree::tree(High~.-Sales, Carseats)
head(model.frame(bad.carseats))   #does not return

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METADATA

• Bug author - Greg Chapman
• Creation time - 2014-03-02 23:56:22 UTC
• Bugzilla link
• Status - CLOSED CONTRIBUTED PACKAGE
• Alias - None
• Component - Add-ons
• Version - R 3.0.2
• Hardware - Other Windows 64-bit
• Importance - P5 minor
• Assignee - R-core
• URL -
• Modification time - 2014-03-03 09:03 UTC

[MichaelChirico]

There is no model.frame.tree in R.

I presume this about package 'tree', not mentioned, and have informed the maintainer.

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METADATA

• Comment author - Brian Ripley
• Timestamp - 2014-03-03 09:03:00 UTC