# Quaternions3

Quaternions are generalizations of the complex numbers that have found applications in computer graphics and many other fields.... 続きを読む >>

# Round, With Tie Breakers, A Prototype

In February and March I published three blog posts about an enhancement request for MATLAB concerning tie breakers with the round function, including the ability to round ties to even. Round One, Round Two and Round Three. Since then, a group of us at MathWorks, organized by my colleague (and academic great-great-grand-descendant) Heiko Weichelt, have been considering the request. We had a virtual design review recently. This post describes a prototype incorporating the features that were discussed at that review.... 続きを読む >>

# Computers That I Have Known

Nick Higham's Numerical Linear Algebra group at the University of Manchester is hosting a conference celebrating Jack Dongarra's 70th birthday July 7 and 8. I am giving a talk, virtually, on July 7. I plan to reminisce about how I did computing in the days before everybody had their own computer in their lap. Here are the slides for the talk, some notes, and some links to this blog for more details.... 続きを読む >>

# Complexity of Computing the Eigenvalues of a Symmetric Matrix1

I am giving a five-minute talk today, May 26, at the virtual seminar on Complexity of Matrix Computations. Here are my slides. Two new MATLAB functions, tred and imtql, instrumented to count flops, are available in symeig.m.... 続きを読む >>

# Computing Eigenvalues of Symmetric Matrices1

Computing Eigenvalues of Symmetric MatricesSee revision.Get the MATLAB code (requires JavaScript) Published with MATLAB®... 続きを読む >>

# Bringing Back the Bucky Ball

The Bucky Ball provides an elegant example of a graph, the connectivity of the Buckminster Fuller geodesic dome.We are also demonstrating publishing this blog with the Live Editor. There is a button... 続きを読む >>

# Mount St. Helens and Matrix Rank

What do Mount St. Helens and the rank of a matrix have in common? The answer is the MATLAB function peaks. Let me explain. Please bear with me -- it's a long story.... 続きを読む >>

# Round, With Ties to Even2

We are considering a MATLAB Enhancement Request to support options for round(x) when x is exactly halfway between two integers.... 続きを読む >>