a node name from which the rendering should proceed to all leaves
indent
token to use for indentation -- will be replicated to depth of
node to be rendered to its left
Value
NULL
Details
Based on keggorthology read of KEGG orthology, March 2 2010.
Specifically, we run wget on
ftp://ftp.genome.jp/pub/kegg/brite/ko/ko00001.keg and use parsing
and modeling code given in inst/keggHTML to generate a data frame
respecting the hierarchy, and then keggDF2graph to
construct the graph.