A new group photo was taken on May 16, 2022—our first in over two years. Most group members are in the photo.
A high resolution version of the photo is available here.
Numerical Linear Algebra Group. By row from the back: Mantas Mikaitis, Xinye Chen, Alban Bloor Rile, Xiaobo (Bob) Liu, Michael Connolly, Nick Higham, Sven Hammarling, Stefan Güttel, Ian McInerney, Bastien Vieuble, Ayana Mussabayeva, Thomas Seleiro, Françoise Tisseur, Marcus Webb.
Congratulations to Jack Dongarra who has received the 2021 ACM A.M. Turing Award. He is cited “for pioneering contributions to numerical algorithms and libraries that enabled high performance computational software to keep pace with exponential hardware improvements for over four decades.”
Dongarra has been Turing Fellow in the Department of Mathematics since 2007, and also holds appointments at the University of Tennessee and Oak Ridge National Laboratory.
In summer 2021 the NLA Group organized a workshop New Directions in Numerical Linear Algebra and High Performance Computing: Celebrating the 70th Birthday of Jack Dongarra. Videos of talks, including one by Dongarra, are available here and provide much insight into Dongarra’s career and achievements.
The photo below shows Dongarra speaking at the 2019 Manchester workshop Advances in Numerical Linear Algebra: Celebrating the Centenary of the Birth of James H. Wilkinson. Wilkinson, seen at the top eight-hand corner of the slide, won the Turing Award in 1971.
Jack Dongarra
The NLA group’s work on stochastic rounding has been featured in a recent article in Science News.
In an interview, Mantas Mikaitis talks about the advantages of stochastic rounding and his work on devising a method to simulate stochastic rounding.
The full article is available here. Other news outlets also picked up the story, such as Tech Xplore (article).
This double minisymposium, organized by Mantas Mikaitis and Nick Higham, took place during SIAM Conference on Parallel Processing for Scientific Computing (PP22) which happened virtually on 23-26 February, 2022. Here we provide slides of some of the talks that were delivered during this minisymposium.
Abstract: The growth of domain-specific hardware devices, such as low- and mixed-precision Matrix-Multiply Accumulate (MMA) accelerators (for example Tensor Processing Units and Tensor Cores), motivates several strands of research in scientific computing. First, algorithm designers aim to benefit from the speedup these hardware devices make possible by adapting algorithms, or parts of them, to run in low or mixed precisions. Second, we need to understand the low level details of how the devices implement floating-point arithmetic and to what extent they satisfy floating-point arithmetic standards. Third, new rounding error analysis is being developed to further support the task of finding the best ways to use the accelerators in order to maximize the accuracy of the results. This minisymposium gathers researchers in scientific computing, numerical analysis, and the standardization and testing of floating-point arithmetics to report the latest research on applying and understanding the MMA hardware.
Numerical Behavior of GPU Matrix Multiply-Accumulate Hardware. Massimiliano Fasi, Örebro University, Sweden; Nicholas J. Higham, Mantas Mikaitis, and Srikara Pranesh, The University of Manchester, United Kingdom; Florent Lopez, ANSYS, Inc., U.S.; Theo Mary, Sorbonne Universités and CNRS, France. Abstract.
Mixed Precision in Linear Algebra. Jack J. Dongarra, University of Tennessee and Oak Ridge National Laboratory, U.S.
Challenges of Mixed-Precision Fast Fourier Transforms from the Instruction Level to at Scale Computations. Lukasz Ligowski, NVIDIA, U.S. Abstract.
Double-Word Arithmetic and Accurate Calculation of Euclidean Norms. Vincent Lefèvre, Inria Paris, France; Nicolas Louvet, Université Claude Bernard Lyon 1, France; Jean-Michel Muller, CNRS, France; Joris Picot, Ecole Normale Superieure de Lyon, France; Laurence Rideau, Inria Sophia Antipolis, France. Abstract.
Online and Offline Precision Tuning in Hardware Accelerators. George A. Constantinides, Imperial College London, United Kingdom. Abstract.
Reducing Data Movement in Mixed Precision LU Factorization with GPU Tensor Cores. Atef Dorai, LIP-ENS Lyon, France; Roman Iakymchuk, Sorbonne Université, France and Fraunhofer ITWM, Germany; Florent Lopez, ANSYS, Inc., U.S.; Theo Mary, Sorbonne Universités and CNRS, France. Abstract.
BLIS: Mixing, Matching, and Extending Precision. Greg Henry, Intel Corporation, U.S.; Devin Matthews, Southern Methodist University, U.S.; Maggie E. Myers, Devangi N. Parikh, Robert A. van de Geijn, and Field G. Van Zee, University of Texas at Austin, U.S. Abstract.
Fluid Simulations Accelerated with 16 bit: Approaching 4x Speedup on A64FX by Squeezing ShallowWaters.jl into Float16. Milan Kloewer, University of Oxford, United Kingdom; Sam Hatfield, European Center for Medium-Range Weather Forecasts (ECMWF) ; Matteo Croci, University of Oxford, United Kingdom; Peter D. Dueben, European Weather Centre, United Kingdom; Tim Palmer, University of Oxford, United Kingdom. Abstract.
The Numerical Linear Algebra Group had a busy year in 2021, despite the pandemic limiting our travel. This post summarizes what we got up to. Publications are not included here, but many of them can be found on MIMS EPrints under the category Numerical Analysis; see also these news stories about our publications.
Nick Higham and Manta Mikaitis released Anymatrix: a MATLAB toolbox that provides an extensible collection of matrices, organized in groups, with the ability to search the collection by matrix properties. See this blog post by Nick and this blog post by Mantas.
We make our research codes available as open source, principally on GitHub; see the repositories of Connolly, Fasi, Higham, Liu, Mikaitis, Pranesh, Zounon.
We also put MATLAB software on MATLAB Central File Exchange and on our own web sites, e.g., the Rational Krylov Toolbox (RKToolbox).
We welcomed new PhD students Ayana Mussabayeva and Alban Bloor Riley.
Thomas McSweeney (Scheduling with Precedence Constraints in Heterogeneous Parallel Computing) and Gian Maria Negri Porzio (Nonlinear Eigenvalue Problems: Theory and Algorithms) successfully defended their PhD dissertations.
Today I have defended my PhD thesis and passed my viva, marking the end of my PhD career at @ManUniMaths. I deeply thank my supervisor @tisseurf for her mentoring during these years, and all the other members of the @nla_grp: they are the best people I have ever met and… 1/2— SIAM (@TheSIAMNews) September 30, 2021
Srikara Pranesh left the group in October 2021 and is now working at V-Labs in Bengaluru. He joined us in 2017 to work on the NLAFET (Parallel Numerical Linear Algebra for Extreme Scale Systems) project and then moved onto the ICONIC project.
Mawussi Zounon left the group in June 2021 to become a senior software engineer at Arm Manchester. He joined us in 2016 to work on the NLAFET project. At the end of the NLAFET project, he continued working with the Numerical Linear Algebra Group as a Knowledge Transfer Partnership (KTP) associate, in partnership with NAG. The KTP, which ended in June 2021, was deemed “Outstanding” by the KTP Grading Panel for its achievement in meeting the KTP Objectives.
Ian McInerney joined the group in December 2021, having completed his PhD in the High Performance Embedded and Distributed Systems (HiPEDS) Centre for Doctoral Training at Imperial College, London, under the supervision of Eric Kerrigan and George Constantinides.
Nick Higham and Françoise Tisseur received funding for work on multi-precision algorithms from Lawrence Livermore National Laboratory under the Exascale Computing Project.
Françoise Tisseur received EPSRC funding to work on mixed precision symmetric eigensolvers.
SIAM Conference on Computational Science and Engineering (virtual), March 1-5: Connolly, Fasi, Higham, Mikaitis, Pranesh, Tisseur.
SIAM Conference on Applied Linear Algebra (virtual), May 17-21: Fasi, Liu.
New Directions in Numerical Linear Algebra and High Performance Computing (virtual) July 7-8, 2021: Hammarling, Higham, Tisseur.
SIAM Annual Meeting 2021(virtual), July 19-23: Connolly, Fasi, Higham, Mary, and Pranesh.
A panel at #SIAMAN21 offered strategies to facilitate the process of #writing and #publishing a book. Read about the techniques of successful authors and the advantages of publishing with SIAM in this month’s issue of SIAM News! sinews.siam.org/Details-Page/a— SIAM (@TheSIAMNews) September 20, 2021
IEEE International Conference on Data Mining (ICDM) 2021, Auckland, New Zealand (virtual), December 7-10: Chen
Stefan Güttel continued to co-organize the E-NLA online seminar series dedicated to topics in Numerical Linear Algebra.
Nick Higham organized a minisymposium on Reduced Precision Arithmetic and Stochastic Rounding at the SIAM Conference on Computational Science and Engineering, March 1-4, 2021.
Theo Mary and Srikara Pranesh organised a two-part minisymposium on Mixed Precision Algorithms for High Performance Scientific Computingr at the SIAM Conference on Computational Science and Engineering, March 1-5, 2021.
Massimiliano Fasi and Xiaobo Liu organised a two-part minisymposium on Computing Functions of Matrices at the SIAM Conference on Applied Linear Algebra, May 17-21, 2021.
Sven Hammarling, Nick Higham and Françoise Tisseur organized the New Directions in Numerical Linear Algebra and High Performance Computing workshop which was held virtually on July 7-8, 2021, celebrating the 70th birthday of Jack Dongarra. Videos from the workshop are available here.
Rob Corless and Nick Higham organized a two-part minisymposium Bohemian Matrices and Applications at the SIAM Annual Meeting (virtual), July 2021.
Nick Higham and Sri Pranesh organized a two-part minisymposium Computational Frontiers in Numerical Linear Algebra at the SIAM Annual Meeting (virtual), July 2021.
Max Fasi was on the organizing committee of the the 9th Matrix Equations and Tensor Techniques Workshop, 9-10 September 2021 in Perugia, Italy.
Nick Higham was been named a 2020 ACM Fellow.
Stefan Güttel was awarded the 2021 James H. Wilkinson Prize in Numerical Analysis and Scientific Computing.
Attending the 2021 James H. Wilkinson Prize in Numerical Analysis and Scientific Computing Lecture titled “Rational Krylov: A Toolkit for Scientific Computing” by Stefan Güttel of University of Manchester? Tune in today at 11:30 am CST. meetings.siam.org/sess/dsp_progr #SIAMCSE21— SIAM (@TheSIAMNews) March 4, 2021
Nick Higham received the George Pólya Prize for Mathematical Exposition from the Society for Industrial and Applied Mathematics (SIAM).
SIAM has announced the 18 recipients of prestigious prizes that will be awarded at the SIAM Annual Meeting, taking place virtually July 19-23, 2021. #SIAMAN21 Learn More: sinews.siam.org/Details-Page/d— SIAM (@TheSIAMNews) July 14, 2021
Nick Higham was awarded the 2022 Hans Schneider Prize by the International Linear Algebra Society (ILAS).
Nick Higham (@nhigham) from the University of Manchester (@OfficialUoM) receives the 2022 Hans Schneider Prize for his fundamental contributions in the analysis of a wide range of numerical linear algebra problems and matrix functions.
— SIAM (@TheSIAMNews) October 19, 2021
Max Fasi took up a Lectureship in Computer Science at Durham University in October 2021.
Professor Nick Higham is featured in a People of ACM profile. “People of ACM” is a bulletin at the Association for Computer Machinery (ACM) highlighting “the unique scientific accomplishments and compelling personal attributes of ACM members who are making a difference in advancing computing as a science and a profession”.
Professor Jack Dongarra was also featured in People of ACM in 2013.
Professor Nicholas J. Higham, University of Manchester
Professor Nick Higham has been awarded the 2022 Hans Schneider Prize by the International Linear Algebra Society (ILAS). The Hans Schneider Prize in Linear Algebra is awarded every three years by ILAS for research, contributions, and achievements at the highest level of Linear Algebra.
Nick is cited for his fundamental contributions in the analysis of a wide range of numerical linear algebra problems and matrix functions. He will present his lecture at the 25th ILAS Conference in Madrid, Spain, June 5-9, 2023.
Professor Nicholas J. Higham, The University of Manchester
The SIAM Annual Meeting 2021 was held virtually, July 19 – 23, 2021. Nick Higham and I organised a two-part minisymposium “Computational Frontiers in Numerical Linear Algebra” that addressed recent algorithmic and software advances in numerical linear algebra. Links to slides from some of the talks are given below.
Minisymposium description: Numerical linear algebra (NLA) is fundamental to many applications in scientific computing. Therefore developing fast algorithms for various NLA problems is crucial to enhance our ability to tackle bigger scientific challenges. Furthermore, NLA software is used as a black box in various applications and hence theoretical guarantees on the computed results are important. Algorithmic development in NLA needs to work in tandem with the ongoing advances in computer hardware. This minisymposium will give a broad overview of various theoretical, algorithmic and software ideas that are being pursued to accelerate NLA problems.
Members of the Numerical Linear Algebra Group will be giving six presentations at the upcoming SIAM Annual Meeting (AN21). They are also organizing the two-part minisymposiums Computational Frontiers in Numerical Linear Algebra (Part 1, Part 2) and Bohemian Matrices and Applications (Part 1, Part 2).The conference will be held virtually, from 19th July to 23rd July, 2021.
Tuesday 20 July
18:30 – 20:30 Massimiliano Fasi
Cpfloat: A C Library for Emulating Low-Precision Arithmetic (poster)
Wednesday 21 July
14:30 – 15:30 Nick Higham
Past President’s Address – Mixed Precision Numerical Linear Algebra with More Realistic Error Bounds
Thursday 22 July
16:45 – 17:10 Massimiliano Fasi
Determinants of Normalized Bohemian Upper Hessenberg Matrices
Friday 23 July
10:15 – 10:40 Theo Mary
Data-Aware Mixed Precision Algorithms
10:45 – 11:10 Srikara Pranesh
Random Matrices Generating Large Growth in LU Factorization with Pivoting
11:15 – 11:40 Michael Connolly
Mixed Precision Randomized SVD
More information on AN21 is available here.
The Society for Industrial and Applied Mathematics (SIAM) has chosen Nick Higham, Royal Society Research Professor and Richardson Professor of Applied Mathematics, as the 2021 recipient of the George Pólya Prize for Mathematical Exposition.
The prize, which is awarded for expository work that communicates mathematics effectively, is named after George Pólya, the Hungarian mathematician who wrote the million-selling book How to Solve It, first published in 1945.
“Pólya was a brilliant researcher, teacher, and expositor of mathematics,” said Higham. “It is an honor to receive this SIAM prize named after him, especially as most of my research and expository writing has been published with SIAM.”
Higham was cited for “the crisp clarity, elegance and accessibility of his mathematical and popular exposition on a broad range of topics in applied mathematics.”
The award ceremony will be held at the 2021 SIAM Annual Meeting, scheduled to be held in a virtual format during July 19-23, 2021. See also the SIAM announcement of the award.
Professor Nicholas J. Higham, University of Manchester. Photo: Rob Whitrow
Numerical Linear Algebra Group 
