Bi-directional determination of sparse Jacobian matrices : algorithms and lower bounds
dc.contributor.author | Saha, Anik | |
dc.contributor.author | University of Lethbridge. Faculty of Arts and Science | |
dc.contributor.supervisor | Hossain, Shahadat | |
dc.date.accessioned | 2015-10-02T21:09:59Z | |
dc.date.available | 2015-10-02T21:09:59Z | |
dc.date.issued | 2015 | |
dc.degree.level | Masters | en_US |
dc.description.abstract | Efficient estimation of large sparse Jacobian matrices is a requisite in many large-scale scientific and engineering problems. It is known that estimation of non-zeroes of a matrix can be viewed as a graph coloring problem. Due to the presence of dense rows or dense columns, unidirectional partitioning does not always give good results. Bi-Directional partitioning handles the problem of dense rows and dense columns quite well[16]. Lower bound to determine the non-zeroes of a sparse Jacobian matrix can be defined as the least number of groups necessary to determine the matrix. For unidirectional partitioning, a good lower bound is given by the maximum number of non-zeroes in any row[4]. For bi-directional determination, both columns and rows must be considered to obtain a lower bound. In this thesis, we provide an easily computed better lower bound. We have developed a heuristic algorithm and an iterative algorithm to determine non-zeroes of sparse Jacobian matrices using Bi-Directional partitioning. Our heuristic algorithm is inspired from graph coloring problems and recursive largest first partitioning of graphs. Our algorithm provides a better result than the existing algorithms. For the iterative method, we have introduced randomization technique to color the vertices of the graph. A part of our work was presented at "Applied Mathematics, Modelling and Computational Science" (AMMCS-2015). | en_US |
dc.embargo | No | en_US |
dc.identifier.uri | https://hdl.handle.net/10133/3760 | |
dc.language.iso | en_CA | en_US |
dc.proquest.subject | 0405 | en_US |
dc.proquest.subject | 0642 | en_US |
dc.proquestyes | Yes | en_US |
dc.publisher | Lethbridge, Alta. : University of Lethbridge, Dept. of Mathematics and Computer Science | en_US |
dc.publisher.department | Department of Mathematics and Computer Science | en_US |
dc.publisher.faculty | Arts and Science | en_US |
dc.relation.ispartofseries | Thesis (University of Lethbridge. Faculty of Arts and Science) | en_US |
dc.subject | sparse matrix | en_US |
dc.subject | Jacobian matrix | en_US |
dc.subject | row and column compressions | en_US |
dc.subject | bi-directional partitioning | en_US |
dc.title | Bi-directional determination of sparse Jacobian matrices : algorithms and lower bounds | en_US |
dc.type | Thesis | en_US |