carve_subtree: Carve out branches to form a new tree.
In autoharp: Semi-Automatic Grading of R and Rmd Scripts

Description Usage Arguments Details Value Examples

This functions keeps only the indicated nodes, returning a new sub-tree.

1	carve_subtree(obj, char_arr)

`obj`	An object of class TreeHarp.
`char_arr`	A vector of 1's and 0's indicating which nodes to keep. The vector should have length equal to the number of nodes in obj.

This returns an error if the sub-tree does not define a new tree.

An object of class TreeHarp.

th3 <- list(a= c(2L,3L,4L), b=NULL, c=c(5L, 6L), d=7L, e=NULL, f=NULL, g=NULL)
carve_subtree(TreeHarp(th3), c(1,0,0,0,0,0,0))
st <- subtree_at(TreeHarp(th3), 4)
plot(st)