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December 31, 2009


As part of his science fair project, my 3rd-grader needed a large number of random strings of 8 digits, in each of which “1” appears four times, and “2”–“5” appear once each.

Posted by distler at 10:55 AM | Permalink | Followups (5)

December 28, 2009

Instiki 0.18

I just released Instiki 0.18.

It’s been half a year, since I announced the release of 0.17 and there’s lots of new stuff. So I guess it’s time for an upgrade

New feature include:

  • Syntax colouring for code blocks: ‘html’, ‘xml’, ‘ruby’, ‘ansic’, ‘javascript’, ‘sqlite’, ‘yaml’ and ‘css’ modes.
  • Source view [suggested by Andrew Stacey]
  • Auto-resizing Textareas scale to fit viewing area.
  • Passenger support (including X-Sendfile support, if the Apache mod_xsendfile module is installed).
  • Upgraded to Rails 2.3.5 and Rack 1.1.
  • Now runs on Ruby 1.9. (If you’re a Passenger user, you may need to upgrade to Passenger 2.2.8, which works around some bugs in Ruby 1.9.1.)
  • Upgraded for itex2MML 1.3.19 (which works under Ruby 1.9, and has several new features, relative to 1.3.15).

and a boatload of bugfixes.

Update (1/7/2010):

Because of some character encoding issues under Ruby 1.9 (mostly affecting My SQL users), I decided to issue a quick update to Instiki 0.18.1. [Thanks to Andrew Stacey for running these issues down.] I also added some new features: (Markdown-Extra-style) fenced code-blocks and ‘fortran’ syntax colouring. [Both courtesy of Jason Blevins.]


 rake upgrade_instiki

before running the new version.

Posted by distler at 11:12 AM | Permalink | Post a Comment

December 21, 2009


One of the disadvantages of having waded into the Lisi affair is that I keep getting asked about related ill-conceived ideas for “theories of everything.” For the most-part, such ideas don’t have a relentless publicity machine behind them. Nor do they receive what can only be described as a credulous reception in certain corners of the Mathematics community. But still, it is assumed that one has an opinion about them.

One such idea is the Spin(3,11)Spin(3,11) “GraviGUT” of Nesti and Percacci. The bosonic fields consist of a connection for a noncompact Spin(3,11)Spin(3,11) gauge group, and a 1-form, θ\theta, transforming in the 14-dimensional vector representation. More formally, we assume that PMP\to M is a Spin(3,11)Spin(3,11) principal bundle, and EME\to M a vector bundle, associated associated to PP via the 14-dimensional vector representation. The fields consist of a connection on PP, and a 1-form, θ\theta, with values in sections of EE.

Posted by distler at 11:23 AM | Permalink | Followups (28)

December 20, 2009


For many years, I was an enthusiastic user of ecto. Unfortunately, Adriaan gradually lost interest, and ecto3 languished – seemingly forever – as bug-ridden, user-unfriendly, beta software. Eventually, he sold it to illuminex, where it continues to languish (though I think they’re actually trying to charge people for using buggy, user-unfriendly beta software).

Anyway, to make a long story short, I’ve switched to MarsEdit, which – unlike ecto3 – is not the least bit painful to use.

To celebrate, I created some MarsEdit TextFilters.

Posted by distler at 11:19 AM | Permalink | Followups (3)

December 14, 2009

So Much For the Concept of “Tree Graph”

Posted by distler at 10:35 AM | Permalink | Followups (5)

December 8, 2009


I’ve been playing around with Google Wave, and the Oxyxy Gadget.

Posted by distler at 5:49 PM | Permalink | Followups (3)