Last night, my wife Cathy and I passed our level 5 test in kuntao. That’s a halfway point to level 10, which is the first “guro” level, roughly equivalent to black belt in a Japanese or Korean art. Ranks aren’t the big deal in kuntao that they are in most Americanized martial arts, but this… Continue reading Halfway up the mountain
Announcing microjson
If you’ve ever wanted a JSON parser that can unpack directly to fixed-extent C storage (look, ma, no malloc!) I’ve got the code for you. The microjson parser is tiny (less than 700LOC), fast, and very sparing of memory. It is suitable for use in small-memory embedded environments and deployments where malloc() is forbidden in… Continue reading Announcing microjson
Never let an invariant go untested
I’ve been blog-silent the last couple of days because I’ve been chasing down the bug I mentioned in Request for help – I need a statistician. I have since found and fixed it. Thereby hangs a tale, and a cautionary lesson.
Request for help – I need a statistician
GPSD has a serious bug somewhere in its error modeling. What it effects is position-error estimates GPSD computes for GPSes that don’t compute them internally themselves and report them on the wire. The code produces plausible-looking error estimates, but they lack a symmetry property that they should have to be correct. I need a couple… Continue reading Request for help – I need a statistician
A Closed Future for Mathematics?
In a blog post on Computational Knowledge and the Future of Pure Mathematics Stephen Wolfram lays out a vision that is in many ways exciting and challenging. What if all of mathematics could be expressed in a common formal notation, stored in computers so it is searchable and amenable to computer-assisted discovery and proof of… Continue reading A Closed Future for Mathematics?
Review: Infinite Science Fiction One
Infinite Science Fiction One (edited by Dany G. Zuwen and Joanna Jacksonl Infinite Acacia) starts out rather oddly, with Zuwen’s introducton in which, though he says he’s not religious, he connects his love of SF with having read the Bible as a child. The leap from faith narratives to a literature that celebrates rational knowability… Continue reading Review: Infinite Science Fiction One
Review: Collision of Empires
Collision of Empires (Prit Buttar; Osprey Publishing) is a clear and accessible history that attempts to address a common lack in accounts of the Great War that began a century ago this year: they tend to be centered on the Western Front and the staggering meat-grinder that static trench warfare became as outmoded tactics collided… Continue reading Review: Collision of Empires
Review: A Call to Duty
A Call To Duty (David Weber, Timothy Zahn; Baen Books) is a passable extension of Baen Book’s tent-pole Honorverse franchise. Though billed as by David Weber, it resembled almost all of Baen’s double-billed “collaborations” in that most of the actual writing was clearly done by the guy on the second line, with the first line… Continue reading Review: A Call to Duty
Review: The Abyss Beyond Dreams
The Abyss Beyond Dreams (Peter F. Hamilton, Random House/Del Rey) is a sequel set in the author’s Commonwealth universe, which earlier included one duology (Pandora’s Star, Judas Unchained) and a trilogy (The Dreaming Void, The The Temporal Void, The Evolutionary Void). It brings back one of the major characters (the scientist/leader Nigel Sheldon) on a… Continue reading Review: The Abyss Beyond Dreams
Request for code review: cvs-fast-export
Sometimes reading code is really difficult, even when it’s good code. I have a challenge for all you hackers out there…
Reality is viciously sexist
Better Identification of Viking Corpses Reveals: Half of the Warriors Were Female insists an article at tor.com. It’s complete bullshit. What you find when you read the linked article is an obvious, though as it turns out a superficial problem. The linked research doesn’t say what the article claims. What it establishes is that a… Continue reading Reality is viciously sexist
Adverse selection and old technology
Yesterday I shipped cvs-fast-export 1.15, with a significant performance improvement produced by replacing a naive O(n**3) sort with a properly tuned O(n log n) version. In ensuing discussion on G+, one of my followers there asked if I thought this was likely to produce a real performance improvement, as in small inputs the constant setup… Continue reading Adverse selection and old technology
Mysterious cat is mysterious
Our new cat Zola, it appears, has a mysterious past. The computer that knows about the ID chip embedded under his skin thinks he’s a dog. There’s more to the story. And it makes us think we may have misread Zola’s initial behavior. I’m torn between wishing he could tell us what he’d been through,… Continue reading Mysterious cat is mysterious
Phase-of-moon-dependent bugs suck
I just had a rather hair-raising experience with a phase-of-moon-dependent bug. I released GPSD 3.11 this last Saturday (three days ago) to meet a deadline for a Debian freeze. Code tested ninety-six different ways, run through four different static analyzers, the whole works. Because it was a hurried release I deliberately deferred a bunch of… Continue reading Phase-of-moon-dependent bugs suck
Master Foo and the Hardware Designer
The newest addition to Rootless Root:
Spam alert
Yes, I’m aware of the spam on the blog front page. The management does not hawk dubious drugs. Daniel Franke and I just did an audit and re-secure of the blog last night, so this is a new attack. Looks like a different vector; previously the spam was edited into the posts and invisible, this… Continue reading Spam alert
Review: Once Dead
Once Dead (Richard Phillips; Amazon Publishing) is a passable airport thriller with some SF elements. Jack Gregory should have died in that alley in Calcutta. Assigned by the CIA to kill the renegade reponsible for his brother’s death, he was nearly succeeding – until local knifemen take a hand. Bleeding, stabbed and near death, he… Continue reading Review: Once Dead
This picture tells a shooting story
Before you read any further, go look at the drawing accompanying the New Tork Times article on the autopsy of Michael Brown, There’s a story in that picture. To read it, you have to be familiar with pistol shooting and the kind of pistol self-defense training that cops and amateur sheepdogs like me engage in.… Continue reading This picture tells a shooting story
Alien cat is alien
One of the reasons I like cats is because I find it enjoyable to try to model their thought processes by observing their behavior. They’re like furry aliens, just enough like us that a limited degree of communication (mostly emotional) is possible. Just now I’m contemplating a recent change in the behavior of our new… Continue reading Alien cat is alien
Demilitarize the police – and stop flinging false racism charges
I join my voice to those of Rand Paul and other prominent libertarians who are reacting to the violence in Ferguson, Mo. by calling for the demilitarization of the U.S.’s police. Beyond question, the local civil police in the U.S. are too heavily armed and in many places have developed an adversarial attitude towards the… Continue reading Demilitarize the police – and stop flinging false racism charges