Floating point arithmetic doesn't get the respect it deserves. Many people consider it mysterious, fuzzy, unpredictable. These misgivings often occur in discussion of vector sums. Our provocatively named SuperSum is intended to calm these fears.... 続きを読む >>
Our technical support group recently received a request for a tool that would convert IBM System/360 hexadecimal floating point numbers to the IEEE-754 format. I am probably the only one left at MathWorks that actually used IBM mainframe computers. I thought we had seen the last of hexadecimal arithmetic years ago. But, it turns out that the hexadecimal floating point format is alive and well.... 続きを読む >>
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 >>
I recently published Round, With Ties to Even and followed that with Round Two. Then, in an email, Andy Bartlett pointed out that my new round function fails for some large values of x between flintmax/2 and flintmax.... 続きを読む >>
I published Round, With Ties to Even a couple of days ago. Steve Eddins and Daniel Dolan immediately had substantive comments. Here is my reaction to their comments.... 続きを読む >>
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 >>
(A slight revision of the post I made a few hours ago.)... 続きを読む >>
In an unpublished 1972 technical report "Conserving confluence curbs ill-condition," Velvel Kahan coined the descriptive term pejorative manifold. In case you don't use it in everyday conversation, pejorative means "expressing contempt or disapproval."... 続きを読む >>
In an unpublished 1972 technical report "Conserving confluence curbs ill-condition," Velvel Kahan coined the descriptive term pejorative manifold. In case you don't use it in everyday conversation, pejorative means "expressing contempt or disapproval."... 続きを読む >>
My colleagues are looking for a matrix to be used in a new benchmark. They've come to the right place.... 続きを読む >>
