The function aims to find out the focus set index for which the true discoveries is the most and all other focus sets that are disjoint with it .
choosepath(startingindex = 1, fsets, lowdv)
The index of focus set that has the first largest number of true discovereis
A list of focus level gene sets,or GO (Gene Ontology) terms
A non-negative integer vector, which are the number of true discovereis, the length of the vector is the same as the list of focus level sets
The function will return an integer or a numeric vector.