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Following my previous post on Optimizing Javascript, I thought I’d write a similar post regarding Python optimization.

Profiling, Profiling, Profiling This seems obvious, but still merits a mention. Don’t optimize your code before profiling it. If you need a profiler, just use firebug’s. Having tests to make sure that your post-profiling code is equivalent to the original is also nice. Later is better than now As is well known, it is usually…

In the following post, the Ulam spiral is described. It’s a very simple object – write down consecutive natural numbers starting from 41 in a square spiral. Curiously, the numbers on the diagonal are primes: Reading this post, I immediately wanted to check how long this property holds. The original blog post suggests: Remarkably, all…

I like my privacy. I also prefer to keep my information secure. I might be a bit more paranoid than the rest, but not extremely so. A short while ago, I discovered something disturbing regarding Firefox. It seems to be a ‘secret everybody knows’, yet Firefox doesn’t say anything about that. What is it? When…

Following Ned Batchelder’s advice I’ve used pngout to minify the png’s on my startup’s web page. It took them down from 641,281 bytes to 338,705. This is quite a nice return for the effort of a download and a single command line: for %i in (*.png) do pngout “%i”

  Image by Mykl Roventine I’ve been running wordpress for a long time now, and luckily so far, it hasn’t been hacked. Of course – this doesn’t prove anything, as I didn’t count hacking attempts. It also doesn’t show it’s unhackable – on the contrary, I believe that my wordpress installation is hackable by a determined…

A few days ago, I wrote up a challenge – to count the number of sets a given set is contained in. In the comments, I touched briefly on the original problem from which the challenge was created, and I’ll describe it in more depth here. In the problem, I am given an initial group…

I didn’t write this one, but I found it’s simplicity and availability so compelling, I couldn’t just not write about it. In a reddit post from a while ago, some commenter named jfedor left the following comment: A little known fact is that you can do the following on any standard Python installation: from turtle…

This is a problem that I encountered a short while ago. It seems like it could be easily solved very efficiently, but it’s not as easy as it looks. Let’s say that we are given N (finite) sets of integers – S. For now we won’t assume anything about them. We are also given another…

Yesterday I gave a presentation on harvesting to the PyWeb-IL group. In the presentation, I described what I learned about harvesting and also gave a concrete example of how to find the “most influential artists” using data from allmusic.com and a (very) naive implementation of PageRank. The PageRank implementation was based on wikipedia word-by-word, and…