Given two nodes that are on the same path to the root, this function
determines the branch that leads to the child node.
Usage
find_branch_num(th, child_id, ancestor_id)
Arguments
- th
A TreeHarp object.
- child_id
An integer node id. It corresponds to the node to trace up
from.
- ancestor_id
An integer node id. It corresponds to the node to trace
down from.
Value
An integer that denotes the branch to follow down (from the ancestor)
to reach the child.
Details
This is used when trying to find a sub-call from a TreeHarp object.
It is useful in determining the indices to use when extracting the sub-call.
Examples
ex3 <- quote(x <- f(y = g(3, 4), z=1L))
t1 <- TreeHarp(ex3, TRUE)
find_branch_num(t1, 8, 3) # should be 1
#> [1] 1
find_branch_num(t1, 5, 3) # should be 2
#> [1] 2
