El lunes, 7 de abril de 2014 12:35:05 UTC-5, David P. Sanders escribió:
>
> Hi,
>
> I need to (conceptually) add a field to the IntDisjointSets data structure
> available in DataStructures.jl, which is basically the size (number of
> elements) in each of the disjoint sets.
>
Sorry, that's not correct -- it's not the number of elements of each set;
rather each set has a certain `size` which is a separate quantity.
I have been playing with it, and all the functions are easy to implement,
except for union!:
the new union! will be a word-for-word copy of the old union!, except that
the information about the size also has to be updated.
Is there some way of avoiding copy-paste in this case?
using DataStructures
import Base.length
type MyDisjointSets
forest::IntDisjointSets
sizes::Vector{Int}
MyDisjointSets(n::Integer) = new(IntDisjointSets(n), ones(n))
end
length(s::MyDisjointSets) = length(s.forest)
num_groups(s::MyDisjointSets) = num_groups(s)
find_root(s::MyDisjointSets, x::Integer) = find_root(s.forest, x)
in_same_set(s::MyDisjointSets, x::Integer, y::Integer) =
find_root(s.forest, x) == find_root(s.forest, y)
> What is the julian way to do this kind of "inheritance"?
> Should I create a new type which *contains* an IntDisjointSets object and
> another Vector, and then define the functions find_root and union! for that
> new structure?
>
> Would there be interest in adding this to DataStructures once it's
> implemented?
>
> Thanks,
> David
>
