Friday, 5 December 2014

The Sum of Things

I got stuck on a question about figuring out the closed form of 'function pesky' in exercise 2-2 in the Skiena book.  Of course it's easy to solve if you do it any other way, but, I tried to use summation algebra and failed miserably.

Where do you find this kind of information?  Why, in the Concrete Mathematics book in chapter 2. The very tome languishing in my shelf that I wimped out of after chapter 1 a long time ago.  Luckily I DID work through chapter 1(some time ago), so revisiting this should be easy-ish.  Maybe.

So since my concentration is all shot to bits at the moment anyway (this house move has me frazzled), I might as well go back to basics and learn some stuff I should have learned properly long ago.

Alternatively I could simply ignore the issue and just chalk this down to 'some you cannot solve' but, I've a lazy nature and, the summation trick is as lazy as it gets, plus it's ever so useful, so...

What happened to the malloc post I promised?  It's in the works.  I'm currently on page 36 of a long survey of different mallocs and pertaining strategies of 78 pages, and whilst I read some of the code that's around (of course, understanding very little, other than 'you-wanna-do-a-what?') it's as slow as my TCP/IP effort.  Mostly because there is a lot of read and as a consequence, a lot to think about.

Little by little as the cat eats the fish is the parole here.  (a bit like packing my house up, sooo much valuable junk).

Other cool stuff I'm currently enjoying:  A book about trees.  And:  Revolutions!