The Closest Pair of Points problem is a standard topic in an algorithms course today, but when I taught such a course fifty years ago, the algorithm was not yet known. Contents California Dreaming Closest Pair of Points Pairs DivCon Center Complexity Timing Software References California Dreaming Imagine you are driving a car on the Harbor Freeway in southern California with typical Los Angeles traffic conditions. Among the many things you might want to know is which pair of vehicles is nearest each other. This is an instance of the Closest Pair of Points problem: Given the location of ..read more

I have just returned from the MathWorks company meeting celebrating our 40th Anniversary. In one of the presentations, Jos Martin described how Parallel MATLAB was introduced almost twenty years ago. Here are a few slides from Jos's talk. Contents Why There Wasn't Any Parallel MATLAB Twenty-seven Parallel MATLABs Distributed Computing Toolbox Supercomputing Conference Bill Gates Now There is a Parallel MATLAB Why There Wasn't Any Parallel MATLAB In MATLAB News and Notes for spring 1995, I wrote a one-page Cleve's Corner titled "Why there isn't any parallel MATLAB." There were three reason ..read more

The Swinging Sticks is a kinetic sculpture that exhibits chaotic motion. The device became very popular after it upstaged Tony Stark in Iron Man 2. My daughter Carolyn gave me a desktop version of Swinging Sticks for Christmas. I immediately set out to simulate it. Contents Chaotic Motion Swinging Sticks Sculpture Code Chaotic Motion Chaotic motion appears random but isn't. Once the motion begins, the initial conditions together with Newton's law of motion, F = ma, determine subsequent behavior. There are no random forces. It may be difficult to predict positions, but they are well-deter ..read more

Nick Higham passed away last Saturday. Nick was a close friend of mine and a great friend of MATLAB. I will leave it to others to describe his research and teaching, his many honors, and his service to our community, especially SIAM. I have just a few, more personal, comments. Contents NA Digest Books MATLAB gallery expm Goodbye NA Digest Monday's NA Digest led off with this from Nick's wife Francoise and his brother Des. Subject: Nick Higham (1961--2024) With great sadness we report that Nick Higham, Royal Society Research Professor and Richardson Professor of Applied Mathematics at ..read more

We have been investigating a recent bug report about fitnlm, the Statistics and Machine Learning Toolbox function for robust fitting of nonlinear models. Contents Quahogs Acidification Separable Least Squares Centering Data Exponential Fitting Results Software Thanks Quahogs The bug report comes from Greg Pelletier, an independent research scientist and biogeochemical modeler in Olympia, Washington. Greg has been studying the vulnerability of sensitive marine organisms to increases in ocean acidification. One of the most important of these organisms is Mercenaria mercenaria, the hard cla ..read more

Season's Greeings Get the MATLAB code (requires JavaScript) Published with MATLAB® R2023a ..read more

This is post number 300 of Cleve's Corner blog. The first post was on June 6, 2012, which is 600 weeks ago. So, I have averaged one post every two weeks for over a decade. The posts were more frequent in the early days and are less frequent today. Contents Vibrating Logo Code vibrating_logo vibrating_logo_frame first frame init_fig Vibrating Logo For my 300-th post, I want to take another look at our MathWorks logo. Here is a modified version of one of the animations that I entered in the recent MATLAB Flipbook Mini Hack. Vibrating Logo The MathWorks company logo is the solution ..read more

The 2023 MATLAB Central Flipbook Mini Hack contest runs from November 6 until December 3. Over 200 entries have been submitted in the first two weeks. Contents New Rules Gallery Personal Favorites Bouncing Bucky Ball Software Thanks New Rules This year's mini hack features short animations. The contest software runs the program you submit to make an animated GIF file with exactly 48 frames and an inner-frame delay time of 1/24 second. So, your animation will run for two seconds, then continuously repeat. If you want periodic motion, you need to be back where you started by frame 48. In pr ..read more

Try your hand at a few exercises involving Exploring Matrices. Contents Qube Simplified Exploring Matrices Exercises Matrix Multiplication Rotations and Scaling Computer Graphics Matrices and Cubes Qube Simplified I have simplified the Qube app by removing these four buttons. solve. The <== key now controls the unscrambling operation. scramble. The ==> key now does six random rotations. order. I never found a satisfactory reference for the group theory of Rubik's cube. score. I never found a use for the nuclear norm. Code for Qube dated 9/24/2023 is included in the ..read more

I have spent much of my career working to bring abstract linear algebra and practical matrix computation closer together. This project is my latest effort. Contents Alibi Exploring Matrices YouTube Videos Matrix Multiplication Rotation and Scaling Computer Graphics Matrices and Cubes Simulink AI and Gorillas Software Thanks Dedication Alibi Over sixty years ago, as a sophomore contemplating a major in mathematics, I took a course entitled Survey of Modern Algebra. We used a now-classic textbook by MacLane and Birkhoff that featured abstract theorems about groups, rings, fields, vector spa ..read more