Given a graph G, a sequence τ = (n1, ..., np) of positive integers summing up to |V (G)| is said to be realizable in G if there exists a realization of τ in G, i.e. a partition (V1, ..., Vp) of V (G) such that each Vi induces a connected subgraph of G on ni vertices. We first give a reduction showing that the problem of deciding whether a sequence with c elements is realizable in a graph is NP-...

In this paper, (d + 1)-pencil lattices on simplicial partitions in Rd are studied. The barycentric approach naturally extends the lattice from a simplex to a simplicial partition, providing a continuous piecewise polynomial interpolant over the extended lattice. The number of degrees of freedom is equal to the number of vertices of the simplicial partition. The constructive proof of this fact l...

Chvátal defined a skew partition of a graph G to be a partition of its vertex set into two non-empty parts A and B such that A induces a disconnected subgraph of G and B induces a disconnected subgraph of G. Skew partitions are important in the characterization of perfect graphs. De Figuereido et al. presented a polynomial time algorithm which given a graph either finds a skew partition or dete...

In this paper, we are concerned with clustering algorithms for vertical partitioning. In particular, we examine the use of a branch-and-bound scheme. An existing algorithm using such a scheme may produce infeasible solutions to some problems. We adopt the same branch-and-bound scheme and develop a new branching strategy to avoid infeasibility. Illustrative examples are used to demonstrate the e...

Consider the partition function S μ( ) associated in the theory of Rényi dimension to a finite Borel measure μ on Euclidean d-space. This partition function S μ( ) is the sum of the q-th powers of the measure applied to a partition of d-space into d-cubes of width . We further Guérin’s investigation of the relation between this partition function and the Lebesgue Lp norm (Lq norm) of the convol...

Given an ordered partition Π = {P1, P2, ..., Pt} of the vertex set V of a connected graph G = (V,E), the partition representation of a vertex v ∈ V with respect to the partition Π is the vector r(v|Π) = (d(v, P1), d(v, P2), ..., d(v, Pt)), where d(v, Pi) represents the distance between the vertex v and the set Pi. A partition Π of V is a resolving partition of G if different vertices of G have ...

Graph partitioning is an important abstraction used in solving many scientific computing problems. Unfortunately, the standard partitioning model does not incorporate considerations that are important in many settings. We address this by describing a generalized partitioning model which incorporates the notion of partition skew and is applicable to a variety of problems. We then develop enhance...

Assume that each vertex of a graph G is assigned a nonnegative integer weight and that l and u are nonnegative integers. One wish to partition G into connected components by deleting edges from G so that the total weight of each component is at least l and at most u. Such an “almost uniform” partition is called an (l, u)-partition. We deal with three problems to find an (l, u)-partition of a gi...

The randomized k-number partitioning problem is the task to distribute N i.i.d. random variables into k groups in such a way that the sums of the variables in each group are as similar as possible. The restricted k-partitioning problem refers to the case where the number of elements in each group is fixed to N/k. In the case k = 2 it has been shown that the properly rescaled differences of the ...

In this paper we study speaker linking (a.k.a. partitioning) given constraints of the distribution of speaker identities over speech recordings. Specifically, we show that the intractable partitioning problem becomes tractable when the constraints pre-partition the data in smaller cliques with non-overlapping speakers. The surprisingly common case where speakers in telephone conversations are k...