Returns a new transitiontrees containing only the queried node and
its descendants. Node names are kept absolute (so the original
pathway is preserved as a key), but the returned object has a
local_root attribute pointing at the queried pathway.
Value
A new transitiontrees whose nodes and edges are restricted
to descendants of pathway. The alphabet, smoothing, and
other hyperparameters are copied unchanged. Printing the subtree
reports the context it was cut at (also stored in
attr(., "local_root") for programmatic use).
Examples
# \donttest{
set.seed(1)
m <- matrix(sample(c("A","B","C"), 200, TRUE), 20)
tr <- context_tree(m, max_depth = 2L, min_count = 3L)
subtree(tr, "A") # prints "subtree of: A" in the banner
#> <transitiontrees> 4 nodes, depth <= 2, 3 states [unpruned]
#> alphabet : A, B, C
#> fit on : 20 sequences, 200 observations
#> smoothing: floor(ymin=0.001, rule=interpolate) min_count = 3
#> subtree of: A
# }