Skip to main content

Once upon and Algorithm - Martin Erwig ***

I've been itching to start reading this book for some time, as the premise was so intriguing - to inform the reader about computer science and algorithms using stories as analogies to understand the process.

This is exactly what Martin Erwig does, starting (as the cover suggests) with Hansel and Gretel, and then bringing in Sherlock Holmes (and particularly The Hound of the Baskervilles), Indiana Jones, the song 'Over the Rainbow' (more on that in a moment), Groundhog Day, Back to the Future and Harry Potter.

The idea is to show how some aspect of the story - in the case of Hansel and Gretel, laying a trail of stones/breadcrumbs, then attempting to follow them home - can be seen as a kind of algorithm or computation and gradually adding in computing standards, such as searching, queues and lists, loops, recursion and more.

This really would have been a brilliant book if Erwig had got himself a co-author who knew how to write for the public, but sadly the style is mostly heavy academic, so the cleverness is rather wasted. Sometimes this comes across in labouring points and at others in spending a lot of effort on what is little more than defining labels for things, rather than providing useful information and context for the reader. It's not that there's not a lot of good material in there, just that it's hard work to dig it out, where I'm sure the whole idea of using the stories was to make it more approachable.

Part of the problem is that the stories themselves don't always work very well as an analogy for what's happening in the computation. So, for example, in the section dealing with sorting he comes up with the task of sorting the tasks and places that Indiana Jones needs to deal with to find the Lost Ark. The unsorted list includes the likes of: disc, sunbeam, Marion and Nepal. The algorithm used involves finding the 'smallest' element... which somehow we are supposed to instantly see is Nepal. Using numbers would not have been so well-linked to the story, but at least it would have made some sense to the reader.

Perhaps the low point is the section that uses a part of the song 'Over the Rainbow' (giving us a tenuous story connection to The Wizard of Oz) to examine language and meaning. If you aren't familiar with musical notation, I'm not sure it's a very helpful analogy... and if you are, some of the ways it's used (particular the assertion of what bars are for) doesn't entirely make sense.

I was a professional programmer for a number of years, but without a computer science background. So I was very familiar with how to do this stuff, but knew nothing of the theory behind it. As such, I found the content of the book really interesting - and the story idea should have made it doubly brilliant - but the execution meant that it didn't deliver anywhere near as well as it could have. Even so, there's a lot to savour, and it's definitely worth persevering to get a feel for why computer programs involve far more than just 'cutting code.'

Hardback:  
Kindle:  

Review by Brian Clegg

Comments

Popular posts from this blog

De/Cipher - Mark Frary ****

I was a little doubtful when I first saw this book. Although it has the intriguing tagline 'The greatest codes ever invented and how to crack them' the combination of a small format hardback and gratuitous illustrations made me suspect it would be a lightweight, minimal content, Janet and John approach to codes and ciphers. Thankfully, in reality Mark Frary manages to pack a remarkable amount of content into De/Cipher's slim form.

Not only do we get some history on and instructions to use a whole range of ciphers, there are engaging little articles on historical codebreakers and useful guidance on techniques to break the simpler ciphers. The broadly historical structure takes the reader through basic alphabetic manipulation, keys, electronic cryptography, one time pads and so on, all the way up to modern public key encryption and a short section on quantum cryptography. 

We even get articles on some of the best known unsolved ciphers, such as the Dorabella and the Voynich ma…

Paul McAuley - Four Way Interview

Paul McAuley won the Philip K. Dick Award for his first novel and has gone on to win the Arthur C. Clarke, British Fantasy, Sidewise and John W. Campbell Awards. He gave up his position as a research biologist to write full-time. He lives in London. His latest novel is Austral.


Why science fiction?

For one thing, I fell in love with science fiction at an early age, and haven’t yet fallen out of love with it (although I have flirted with other genres). For another, we’re living in an increasingly science-fictional present. Every day brings headlines that could have been ripped from a science-fiction story. Giant robot battle: Who knew a duel between chainsaw-armed mech suits could be so boring? for instance. Or, Roy Orbison hologram to embark on UK tour in 2018. And looming above all this, like Hokusai’s famous wave, are the ongoing changes caused by global warming and climate change, which is just one consequence of human activity having become the dominant force of change on the planet…

Karl Drinkwater - Four Way Interview

Karl Drinkwater is originally from Manchester, but has lived in Wales half his life. He is a full-time author, edits fiction for other writers and was a professional librarian for over twenty-five years. He has degrees in English, Classics and Information Science. When he isn't writing, he loves exercise, guitars, computer and board games, the natural environment, animals, social justice, cake and zombies - not necessarily in that order. His latest novel is Lost Solace.

Why science fiction?

My favourite books have always been any form of speculative fiction. As a child I began with ghost stories, which were the first books to make me completely forget I was reading. By my teenage years I was obsessed with fantasy, science fiction, and horror. Although I read literary and contemporary books, non-fiction, historical works, classics and so on, it is speculative fiction that I return to when I want escape and wonder. When I read reviews of my last book, the fast-paced novella Harvest Fe…