Monthly Archives: July 2012

Why computers were invented

From a lecture by Gregory Chaitin: We all know that the computer is a very practical thing out there in the real world … But what people don’t remember as much is that really — I’m going to exaggerate, but

Posted in Computing, Math

Email, RSS problem resolved

There was a problem that caused this blog not to work with some RSS readers. Also, email subscribers were not receiving notices of new posts. Both problems have been resolved. For more info, see 3.5 ways to subscribe to this

Posted in Uncategorized

Interview with Michael Hammel, author of The Artist's Guide to GIMP

Michael J. Hammel is the author of The Artist’s Guide to GIMP, a book I reviewed three weeks ago. The following interview is based on my correspondence with Michael.

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Posted in Graphics

Ubuntu Made Easy

I like books from No Starch Press. (This isn’t some sort of paid endorsement; I don’t make any money from them. They give me books to review, but that’s kinda necessary if I’m going to review them.) Their books are

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Posted in Computing

Keeping multiple programming languages straight

Someone sent me an email asking how I use multiple programming languages and how I keep them straight. I thought I’d write my answer here in case someone else had the same question. I’ve learned programming languages out of a

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Posted in Software development

Epics in 99 seconds

Jon Cozart’s video Harry Potter in 99 Seconds has been viewed over 10 million times on YouTube. Today he posted a similar video, Lord of the Rings in 99 Seconds: A couple more of Jon’s videos I’d recommend: Paper Beatbox

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Posted in Uncategorized

Avoiding underflow in Bayesian computations

Here’s a common problem that arises in Bayesian computation. Everything works just fine until you have more data than you’ve seen before. Then suddenly you start getting infinite, NaN, or otherwise strange results. This post explains what might be wrong

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Posted in Statistics

Editing by semantic units

The most basic text editor commands operate on lines and characters: move up or down a line, delete the next or previous character, etc. More advanced commands operate on context-specific semantic units. In the context of English prose, this means

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Posted in Computing

Trick for computing log(1+x)

Charles Karney showed me a clever trick for computing log(1+x). It only takes a couple lines of code, but those lines are not obvious. If you understand this trick, you’ll understand a good bit of how floating point arithmetic works.

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Posted in Computing

Giveaway: PowerShell in Depth

About a month ago I gave away a copy of Learn Windows PowerShell 3 in a Month of Lunches that Manning provided. Now I’m giving away a copy of PowerShell in Depth: An administrator’s guide by Don Jones, Richard Siddaway,

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Posted in PowerShell

Trivial

Many of the things I once thought were trivial I now think are important. That is, I used to think they were trivial in the modern sense of being unimportant. Now I think they’re trivial in the classical sense of

Posted in Business

80-20 software II

My previous post addressed an objection to apply the 80-20 rule to software. Namely, that even if every user uses only a small portion of the features, they use different portions, and so you can’t remove any of it. In

Posted in Business, Software development

80-20 software

The 80-20 rule says that often 80% of your results come from 20% of your effort. Applied to software, 80% of your customers may only use 20% of the features. So why not just develop that 20% and let the

Posted in Software development

Binomial coefficient trick

Binomial coefficients are simplest to work with when the arguments are non-negative integers, but more general arguments are possible and useful. Concrete Mathematics argues that the most useful case is when the top index is real and the bottom index

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Posted in Math

Deniers, skeptics, and mavericks

Suppose a scientist holds a minority opinion. There’s a trend in journalism to call him a denier if you think he’s wrong, a skeptic if you don’t care, and a maverick if you think he may be right. If this

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Posted in Science