Fast And Scalable Complex Network Descriptor Using Pagerank And Persistent Homology

The PageRank of a graph is a scalar function defined on the node set of the graph which encodes nodes centrality information of the graph. In this article we use the PageRank function along with persistent homology to obtain a scalable graph descriptor and utilize it to compare the similarities between graphs. For a given graph G(V,E), our descriptor can be computed in O(|E|α(|V|)), where α is the inverse Ackermann function which makes it scalable and computable on massive graphs. We show the effectiveness of our method by utilizing it on multiple shape mesh datasets.

Fast And Scalable Complex Network Descriptor Using Pagerank And Persistent Homology
Mustafa Hajij, Paul Rosen, and Elizabeth Munch
International Conference on Intelligent Data Science Technologies and Applications (IDSTA), 2020

Parallel Mapper

The construction of Mapper has emerged in the last decade as a powerful and effective topological data analysis tool that approximates and generalizes other topological summaries, such as the Reeb graph, the contour tree, split, and joint trees. In this paper we study the parallel analysis of the construction of Mapper. We give a provably correct parallel algorithm to execute Mapper on a multiple processors. Our algorithm relies on a divide and conquer strategy for the codomain cover which gets pulled back to the domain cover. We demonstrate our approach for topological Mapper then we show how it can be applied to the statistical version of Mapper. Furthermore, we discuss the performance results that compare our approach to a reference sequential Mapper implementation. Finally, we report the performance experiments that demonstrate the efficiency of our method. To the best of our knowledge this is the first algorithm that addresses the computation of Mapper in parallel.

Parallel Mapper
Mustafa Hajij, Basem Assiri, and Paul Rosen
Proceedings of the Future Technologies Conference, 2020.

An Efficient Data Retrieval Parallel Reeb Graph Algorithm

The Reeb graph of a scalar function that is defined on a domain gives a topologically meaningful summary of that domain. Reeb graphs have been shown in the past decade to be of great importance in geometric processing, image processing, computer graphics, and computational topology. The demand for analyzing large data sets has increased in the last decade. Hence, the parallelization of topological computations needs to be more fully considered. We propose a parallel augmented Reeb graph algorithm on triangulated meshes with and without a boundary. That is, in addition to our parallel algorithm for computing a Reeb graph, we describe a method for extracting the original manifold data from the Reeb graph structure. We demonstrate the running time of our algorithm on standard datasets. As an application, we show how our algorithm can be utilized in mesh segmentation algorithms.

An Efficient Data Retrieval Parallel Reeb Graph Algorithm
Mustafa Hajij and Paul Rosen
Algorithms: Special Issue on Topological Data Analysis, 2020