Using gadgets to translate combinatorial problems into exact cover instances, and how to avoid the gadgets using multiset covers.
“Cambridge CTC is currently undergoing some soul-searching about the future of the Sunday all-day ride…”
“I was disappointed that Tidhar hadn’t been more daring. But maybe that’s too much too ask of any author in the current political climate.” A review of Lavie Tidhar’s 2011 novel.
“There was a hard frost overnight, and although the sun was shining, it was just a couple of degrees above zero…”
“Interactive completion works poorly in the case of changelists and jobs, because all you get when you type TAB is a list of opaque identifiers that give you no help in choosing the item you want.”
“It is stressful to know that something is wrong in your code, but not to know what it is or how to find it, and to have it hanging over your head day after day as you fail to make progress towards solving it. This nightmare scenario is the driver behind Ellen Ullman’s 2003 novel The Bug.”
Google Maps has not been properly localized to the UK, so it’s useless for finding your way about rural Hertfordshire and Essex.
Drawing the triangulations of an oriented n×n square using only lines joining the 4n integer points around the edge of the square.
Despite the claim appearing in a BBC headline, it’s not the case that one in three journeys in Cambridge is by bike.
Computing the number of ways to triangulate an oriented n×n square using only lines joining the 4n integer points around the edge of the square.
It doesn’t take long to reach a ‘mature programming environment’ in which complexity is overwhelming and change is expensive and error-prone. We’re all programmer–archaeologists now.
Truth tables, graph colourings and a surprising sequence in Project Euler problem 209.
I’ve forked the abandoned Emacs/Perforce integration, and started fixing it. In particular, it no longer hangs Emacs when it can’t connect to the Perforce server.
“It was chilly out: just barely above freezing, and there was a cold north-easterly wind. Just the kind of day on which it would have been nice to sit in a warm house…”
A debugging war story: “Bug 142 was especially mysterious because it happened after the program quit running…”
“Malthusianism is a topic that many science fiction writers have tackled, but the genre can not be said to have come out looking particularly good.” A review of Adam Roberts’ 2011 novel By Light Alone.
On Sunday 2nd September I organized three audax rides with the support of CTC Cambridge.
In his final novel Fiasco, Stanisław Lem returns to one of his idées fixes, the impossibility of meaningful contact with aliens.
“Bad reviews are a basic fact of literary life, you might have thought…” Some thoughts on the reaction to Liz Bourke’s review of Michael J. Sullivan’s fantasy novel Theft of Swords.
The public perception of law-breaking among cyclists, how this arises and persists through cognitive biases, and some consequences for campaigners.
All right-thinking people are aesthetic relativists, and for us this means that there’s a lacuna in most reviews: who’s to say, for example, that “characterization” is an appropriate yardstick to judge the work under examination?
What links J. J. Abrams’ 2009 film Star Trek with Christopher Tolkien’s History of the Lord of the Rings?
In which we go to Bury St Edmunds to see the start of stage 7 of the Tour of Britain.
A surprising fact about Python: it cannot be expressed by an operator precedence grammar.
A review of Adam Roberts’ 2007 novel Splinter. At the same time, the narrative does its best to assist in the denial: instead of a science-fictional examination of the catastrophe, the story heads off into middlebrow psychological territory…
A review of Adam Roberts’ 2006 novel Gradisil. Merely pastiching the surface features of this genre won’t by itself produce something that’s recognizable as ‘hard’ sf to the aficionados.
A review of Ian McDonald’s 2004 novel River of Gods. “I would have liked a bit less of the ontological mystery and the big sf ending: I would have been quite happy to carry on with the tour.”
Post-processing a critical edition of the Ben Jonson play for Project Gutenberg Distributed Proofreaders.
A bug report (mostly so that other people who encounter the problem can search for and find the workaround).
Supposing, just supposing, that you actually wanted to make your dots line up vertically in Emacs, how would you go about it?
“How can I put these keen new riders off the club, I thought to myself? How about taking them down the muddiest lane in Hertfordshire?”
A review of Stephen Baxter’s novels Space (2000) and Origin (2001), the second and third books in the Manifold trilogy. “If you’re looking for serene contemplation of disaster and suffering, Baxter’s your man.”
A finished game, with smooth gameplay and polished graphics, gives little evidence of the many twists and turns along the path of development. Here, in twenty-four screenshots of level 24, I show some of the trials, mistakes, and modest triumphs from the development of Floe.
“The selection of destinations made route-setting quite a challenge.”
The translator of Notre-Dame de Paris gives the impression of not having read his own book.
In how many ways can you pack 54 “S” tetracubes into a 6×6×6 cube?
A review of Charles Stross’s 2009 science fiction novel Saturn’s Children, with analyses of the problems with the narrative voice and some of the flaws in the world-building.
A review of the 2003 novel Absolute Friends, in which John le Carré contrasts the Cold War and the War on Terror through the viewpoints of the two spies of the title.
An appeal for the Royal Mail’s Postcode Address File to be freely licensed to individuals and not-for-profit organizations.
A criticism of Robin Lustig’s absurd and offensive explanation for Japan’s low fertility.
Emacs 23.1 was released on 2009-07-29. In this review, I describe some interesting and useful features of this release, and give some historical background to multilingual support in Emacs.
While taking part in this study (run by the MRC Epidemiology Unit at the Institute of Metabolic Science) I amused myself thinking about possible sources of bias.
An e-mail exchange I had a few years ago with “Dr. Phill Edwards” of the British National Party.
Some comments on the sabotage of the Étape Caledonia and the lorry driver who nearly killed Boris Johnson.
A look at the National Audit Office report Improving road safety for pedestrians and cyclists in Great Britain. “You can see that the normalized figures are not nearly so flattering to the UK. Is this just plain incompetence, or a deliberate attempt to mislead?”
A commentary on Adam Roberts’ review of Greg Egan’s novel Incandescence in Strange Horizons.
The cost of and responsibility for snow preparedness: “it’s not just a matter we can leave to government, we all have things to do.”
A serious crash in the Apple Mail application, with some analysis and a possible remedy. “It’s a bit worrying that the entire world can make my mail application crash just by sending me some junk mail.”
A review of the 2007 Nintendo Wii game Super Paper Mario by Intelligent Systems, directed by Ryota Kawade. “Super Paper Mario has two significant innovations. One is graphically and conceptually spectacular, and was hyped in the game’s advertising, and is somewhat of a failure. The other is subtle, little commented on, and a big success.”
A review of the BBC/HBO television drama, with particular attention to the accuracy of the depiction of the science. “If these stars on this photographic plate of the eclipse overlap with the comparison plate, Einstein’s theory is wrong and Newton’s theory holds. If there is a gap between the two images, then the sun’s gravitational field has shifted the stars’ position, and we have a new theory of gravity.”
How a harmless piece of advice to the staff of Bournemouth Borough Council was inflated by The Telegraph into a nationwide cultural crisis.
OpenStreetMap has better coverage of Cambridge than Google Maps. Google Maps combines mapping data from many sources. Why doesn’t it make use of OpenStreetMap?
A letter to David Howarth MP, asking him to work to defeat Home Secretary Jacqui Smith’s proposal to create a government database of telephone calls and e-mails.
A review of Incandescence by Greg Egan. “In a genre dominated by fantasy dressed in a spacesuit instead of a wizard’s robe, Greg Egan stubbornly sticks to extrapolations from the physics we know. He rules out from his fiction faster-than-light travel or communication, or spaceships that couldn’t possibly be fueled by any form of energy we know. This self-denying ordinance deprives him of the props and conventions of the genre: no galaxy-spanning empires or interstellar wars for Egan.”
I demolish an absurd article about cycle commuting from the BBC.
Discussion of video game build pipelines and the development difficulties that they entail.
The trouble with the build tool
make is that because it uses file modification dates to determine whether a dependency has changed, it often rebuilds targets unnecessarily.
An account of a walk I did back in 2002, from Little Town in the Newlands valley in the Lake District, to Buttermere, and back. (In the form of a map with mouseover text.)
There are many thousands of mortgage calculators on the web that compute the monthly payments based on the capital sum, interest rate, and duration. But this one lets you compute any of these four values based on the other three.
A review of Matter by Iain M. Banks. “The book initially appears to be about the political and military conflict between two humanoid civilizations. But a kind of pull-back reveals that this conflict is a small event taking place in a corner of a much vaster canvas, like two colonies of ants fighting over a mound of earth in a city park.”
A look at house prices in December 2007. “I’ve been wondering about what the UK housing market crash is going to look like, and how far prices might fall.”
Smart quotes mode, a minor mode for Emacs 22 that makes it convenient to type ‘smart’ “quotes”.
Why rules can’t tell us how to make good video games; we need understanding of their purpose and effects as well. With an extended digression on neoclassicism and John Dryden.
An analysis of the dispute between the Bishop of Manchester and the video game developer Insomniac over the use of Manchester Cathedral as a setting in the game Resistance: Fall of Man.
Tactics and tips for winning at Quest Mode in Zoonami’s Zendoku, a video game for the Nintendo DS and Sony PSP. With lots of diagrams.
A C programming language technique for embedding relations (tables of data) into programs in a way which is easy to check, safe to update, and requires no tools other than the C preprocessor.
Why video games on the Sony PlayStation Portable take so long to load, and what game developers can do to reduce loading times.
Commentary on an extract from the television series Miracle Planet II, portraying a collision between a small planetoid and Earth, of similar scale to ones which occurred during the “late heavy bombardment” of the Hadean era (about 4 billion years ago).
It’s common and convenient to represent relational databases in the form of spreadsheets, especially using Microsoft Excel. But it’s surpisingly hard to carry out relatively simple database operations on such spreadsheets. This article explains how to implement simple selects and joins as Excel formulae.
The structure of the puzzles in the Nintendo 64 video game The Legend of Zelda: Ocarina of Time. With diagrams and maps.
A study of the errors found and fixed during the development, testing and release history of the adventure Christminster, together with a suggested categorization of defects in adventure games.
Lists the requirements for a statement coverage tool for Python, describes some issues in design and implementation, and compares
coverage.py with other statement coverage implementations.
A text adventure game set in the ancient university town of Christminster. A telegram from your brother Malcolm, a teacher at Biblioll College, draws you in to investigate the mystery of his disappearance, the history of the college, and the ambitions of the scheming Doctor Jarboe and Professor Bungay…