Posts filed under the 'PCPlus' category


PCPlus 286: Cutting cloth

Come October 2009, it was time to write about some algorithm I knew nothing about. And so it was that I delved into two-dimensional bin packing; prompted by a reader question about how to cut cloth efficiently and aiming for the smallest waste possible. […]

READ MORE

PCPlus 285: Calculating Pi

With the September 2009 article, I decided to present a discussion of how the constant π (pi) was calculated in antiquity and over the ages, together with a layman’s rehash of an article I’d written a while ago on how to write a program to calculate it. The nice thing about writing code to calculate π is that it shows off Machin’s formula and writing a minimal “big number” library to perform the calculation. […]

READ MORE

PCPlus 284: Solve computational geometry problems

For some reason, for August 2009’s article, I decided to take a bite out of computational geometry; what can only be described as a ruddy large subject. I mean, it’s huge. And it’s mathematical, to boot. I must have been delusional. Anyway, I touched on three fairly simple and well-known algorithms, well-known because they date from the very early days of computer science. […]

READ MORE

PCPlus 283: Learning the ropes

For July 2009, I managed to snuff out something about ropes, a kind of heavier programming type than string. Apart from the pun/joke, it was an interesting article to research. I have no recollection any more about how I came across the rope type; presumably it was through a late night surfing session, fueled with some microbrew. […]

READ MORE

PCPlus 282: Understanding ternary trees

June 2009’s article was a reversion to what might be called straight computer science after a few months of layman’s topics (indexing the internet, spellchecking, etc) and covered ternary trees. Quick overview: ternary trees are a speedy, space-efficient data structure for storing large numbers of key-value pairs that in certain situations are better than hash tables. […]

READ MORE

PCPlus 281: Indexing the Internet

I write a monthly column for PCPlus, a computer news-views-n-reviews magazine in the UK (actually there are 13 issues a year — there’s an Xmas issue as well — so it’s a bit more than monthly). The column is called Theory Workshop and appears in the Make It section of the magazine. When I signed up, my editor and the magazine were gracious enough to allow me to reprint the articles here after say a year or so. What I’ll do is publish the article from a year ago or so here when I purchase the current issue. […]

READ MORE

Ray tracing image from June 2010’s PCPlus

I’ve just sent off June 2010’s article for PCPlus to my editor, just a smidgeon late. A couple of days is all. It’s on ray tracing, something I’ve wanted to discuss and play around with for a while. I downloaded POV-Ray, an open-source ray tracing renderer for Windows, OSX, and Linux to use as a test-bench, and spent some fun hours with it. […]

READ MORE

PCPlus 280: Writing a spellchecker

I write a monthly column for PCPlus, a computer news-views-n-reviews magazine in the UK (actually there are 13 issues a year — there’s an Xmas issue as well — so it’s a bit more than monthly). The column is called Theory Workshop and appears in the Make It section of the magazine. When I signed up, my editor and the magazine were gracious enough to allow me to reprint the articles here after say a year or so. What I’ll do is publish the article from a year ago or so here when I purchase the current issue. […]

READ MORE

PCPlus 279: JPEG compression

I write a monthly column for PCPlus, a computer news-views-n-reviews magazine in the UK (actually there are 13 issues a year — there’s an Xmas issue as well — so it’s a bit more than monthly). The column is called Theory Workshop and appears in the Make It section of the magazine. When I signed up, my editor and the magazine were gracious enough to allow me to reprint the articles here after say a year or so. What I’ll do is publish the article from a year ago or so here when I purchase the current issue. […]

READ MORE

PCPlus 278: Rainbow tables

I write a monthly column for PCPlus, a computer news-views-n-reviews magazine in the UK (actually there are 13 issues a year — there’s an Xmas issue as well — so it’s a bit more than monthly). The column is called Theory Workshop and appears in the Make It section of the magazine. When I signed up, my editor and the magazine were gracious enough to allow me to reprint the articles here after say a year or so. What I’ll do is publish the article from a year ago or so here when I purchase the current issue. […]

READ MORE