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Marketing emails, part deux

Amazingly it seems, crass, irrelevant – and dare I say it – spammy marketing emails are still going strong and arriving by the couple-of-dozen-plus every day in my inboxes since my last post about the subject (now two years ago!). I’m also seeing more and more where they start off by saying something along the lines of “I researched you on LinkedIn,” but that’s a post for another day. […]

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Subtracting AddThis

Back in June Mozilla released the latest version of the Firefox browser with an oft-requested feature turned on by default. The feature? Blocking web trackers. Excellent news, especially to a Firefox addict like me. […]

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Coincidence, nostalgia

I’ve had my Audi A3 for over nine years now, and will probably keep it for a while longer. Reason? It’s a manual transmission, which I prefer, and Audi no longer import manuals. Also, I’m now used to not having a car payment, be it lease or loan, and have no desire to embark on that journey again. So, at just over 10K miles per year, it ticked over the magic 100K miles just over a month ago. Nice! […]

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HP19B II Business Calculator

What with all the news about a possible recession due to an inverted yield curve (now, there’s a possible post, given my work for a Swaps trading group a while back), and given that someone commented on one of my old posts about a calculator in my collection, I thought it was about time to show off another one. This time we’re going to talk Business. […]

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My most recent sunk cost fallacy

So I have this mini PC in my office that I use for various personal apps and data, stuff I don’t want on my laptop in case that goes missing, gets confiscated or nicked, etc, when I travel. Ultra-cautious, moi? […]

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Hash tables – part one

Next in my occasional series of “reprints” from The Delphi Magazine is a series of articles about one of my favorite data structures, the hash table. […]

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Priority queue – part three

You might have thought that the last couple of posts would have done it for the priority queue – after all, we have the optimal heap implementation for it – but no. There are a couple more fun bits. Let’s investigate a little bit more. […]

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Priority queues – part two

Last time, we introduced the concept of a priority queue data structure, and illustrated it with a couple of simple implementations using an array: firstly by adding new items at the end, and then getting the highest priority item by searching through the array; secondly by maintaining the array in sorted order by priority, forcing new items to be inserted in the correct position in the array, and getting an item is merely removing it from the end of the array. I called these fast insertion/slow deletion and slow insertion/fast deletion implementations. […]

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Priority queues – part one

First up in my “reprints from The Delphi Magazine, cast in JavaScript” posts must be the priority queue. It is after all, an important data structure, can be implemented quickly (although perhaps in not a very efficient manner), and introduces an excellent algorithm, the heap. […]

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Articles for The Delphi Magazine

For some time now, I’ve been pondering whether or not to post my old articles from The Delphi Magazine here on my blog. I supplied Chris Frizelle, the editor, with algorithm articles for a good nine years from November 1997 (with an eight month hiatus while I worked at Microsoft: at the time they frowned upon that kind of thing, especially writing about Delphi and not C# – eek!), under the soubriquet Algorithms Alfresco. It would not be hard to discern that that the early ones formed the basis for my algorithms book. […]

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