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Tagged: math

[blog] Music theory for nerds

Not music nerds, obviously.

I don’t know anything about music. I know there are letters but sometimes the letters have squiggles; I know an octave doubles in pitch; I know you can write a pop song with only four chords. That’s about it.

The rest has always seemed completely, utterly arbitrary. Why do we have twelve notes, but represent them with only seven letters? Where did the key signatures come from? Why is every Wikipedia article on this impossible to read without first having read all the others?

A few days ago, some of it finally clicked. I feel like an idiot for not getting it earlier, but I suppose it doesn’t help that everyone explains music using, well, musical notation, which doesn’t make any sense if you don’t know why it’s like that in the first place.

Here is what I gathered, from the perspective of someone whose only music class was learning to play four notes on a recorder in second grade. I stress that I don’t know anything about music and this post is terrible. If you you so much as know how to whistle, please don’t read this you will laugh at me.

[blog] Perlin noise

I used Perlin noise for the fog effect and title screen in Under Construction. I tweeted about my efforts to speed it up, and several people replied either confused about how Perlin noise works or not clear on what it actually is.

I admit I only (somewhat) understand Perlin noise in the first place because I’ve implemented it before, for flax, and that took several days of poring over half a dozen clumsy explanations that were more interested in showing off tech demos than actually explaining what was going on. The few helpful resources I found were often wrong, and left me with no real intuitive grasp of how and why it works.

Here’s the post I wish I could’ve read in the first place.

[blog] The case for base twelve

Decimal sucks.

Ten is such an awkward number. Its only divisors are two and five. Two is nice, but five? Who cares about five? What about three and four?

I have a simple solution to all of these non-problems and more, which is: we should switch to base twelve.

[blog] Heteroglot: #16 in Pascal, #17 in Inform 7

I was thinking about doing a problem for heteroglot — my quest to solve every Project Euler problem in a different programming language. (They’re adding new problems much more quickly than I’m solving them, so so far I’ve made negative progress.) Then I discovered I’d already done two, but never wrote about either of them. Oops! Here’s a twofer, then.

This post necessarily gives away the answers, so don’t read this if you’d like to solve the problems yourself.

[blog] Heteroglot: #15 in COBOL

Introduction

Many moons ago, I started a ridiculous quest to solve every Project Euler problem, in order, with a different programming language. I called it “heteroglot“.

Partway through that, I gave myself the additional unwritten rule that the next language would be selected by polling the nearest group of nerds. This has resulted in math problems solved in such wildly inappropriate languages as vimscript, MUMPS, LOLcode, and XSLT.

It’s been a while since I did one of these, but I still remember that the next language I’m stuck using is COBOL. I don’t know who suggested it, but I hope he chokes on a rake. ♥

I figure if this is interesting to me, it might be interesting to someone else. So let’s learn some math and/or COBOL.