Update src/coloring.jl

Author: blegat

src/coloring.jl

@@ -431,7 +431,10 @@ struct TreeSet{T}
     reverse_bfs_orders::Vector{Tuple{T,T}}
     "For a tree index `1 <= k <= nt`, `is_star[k]` indicates whether the `k`th three is a star."
     is_star::Vector{Bool}
-    "`tree_edge_indices[1]` is one and `tree_edge_indices[k+1] - tree_edge_indices[k]` is the number of edges in the `k`th tree"
+    """
+    `tree_edge_indices[1]` is one and `tree_edge_indices[k+1] - tree_edge_indices[k]` is the number of edges in the `k`th tree.
+    One can think of it as a kind of fused vector of offsets (similar to the `colptr` field of `SparseMatrixCSC`) of all trees together.
+    """
     tree_edge_indices::Vector{T}
     "numbers of 2-colored trees for which trees sharing the same 2 colors have disjoint vertices"
     nt::T