### The Piral

Do you ever think to yourself, "If I took the first 400 digits of pi and drew lines proportional to each of the digits with a fixed angle between each line what it would look like? And then if I change the angle what an animation of that would look like?" Probably not, but I did on the bus home tonight and so with a bit of Processing here's a little animation that I'm dubbing "The Piral".

It starts with the angle between segments as 90 degrees and works its way up to a straight line. The length of each little segment is proportional to the digit of pi (i.e. 3x, 1x, 4x, 1x, 5x, etc.). As pi swirls around it sometimes stretches itself out, and sometimes bunches together, ultimately it spirals ever larger until it becomes a line.

Strangely pleasing to watch.

PS Before you ask. Here's the code
```int w = 1024;
int h = 768;

void setup()
{
size( w, h );
strokeWeight(2);
background(255);
frameRate(30);
}

String pi = "314159265358979323846264338327950288419716939937510
58209749445923078164062862089986280348253421170679821
48086513282306647093844609550582231725359408128481117
45028410270193852110555964462294895493038196442881097
56659334461284756482337867831652712019091456485669234
60348610454326648213393607260249141273724587006606315
58817488152092096282925409171536436789259036001133053
0548820466521384146951941511609";

void draw()
{
background(255);
float cx = w / 2;
float cy = h / 2;
float angle = 0;

for ( int i = 0; i < pi.length(); ++i ) {
float d = float(pi.substring(i,i+1))+1;
float ex = cx + d * cos(radians(angle)) * 3;
float ey = cy + d * sin(radians(angle)) * 3;
line( cx, cy, ex, ey );

stroke(255/d, 25*d, 64/d);
if ( angle >= 360 ) {
angle -= 360;
}
cx = ex;
cy = ey;
}

if ( ad < 0 ) {
noLoop();
}
}
```

Ruben Berenguel said…
This is... odd. But I share your passion for doing odd programs that you think no-one else may find interesting. I found it interesting ;)

Cheers,

Ruben
Anonymous said…
Odd. In reverse it would be an accurate simile of DNA wrapping around histones in eukaryotes.

Most apt.
Francis Turner said…
Not only odd and interesting but a whole new language to play with. As I'm currently struggling with some data visualization issues and have a long plane ride to Japan on Monday this looks very very useful

I'm sorry you shut down usethesource by the way. It was an interesting place until the spammers discovered it.

### Your last name contains invalid characters

My last name is "Graham-Cumming". But here's a typical form response when I enter it:

Does the web site have any idea how rude it is to claim that my last name contains invalid characters? Clearly not. What they actually meant is: our web site will not accept that hyphen in your last name. But do they say that? No, of course not. They decide to shove in my face the claim that there's something wrong with my name.

There's nothing wrong with my name, just as there's nothing wrong with someone whose first name is Jean-Marie, or someone whose last name is O'Reilly.

What is wrong is that way this is being handled. If the system can't cope with non-letters and spaces it needs to say that. How about the following error message:

Our system is unable to process last names that contain non-letters, please replace them with spaces.

Don't blame me for having a last name that your system doesn't like, whose fault is that? Saying "Your last name …

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I wanted to know what all the possible symmetrical watch faces are and so I wrote some code using Processing. Here's the output (there's one watch face missing, 00:00 or 12:00, because it's very boring):

The key to writing this is to figure out the relationship between the hour and minute hands when the watch face is symmetrical. In an hour the minute hand moves through 360° and the hour hand moves through 30° (12 hours are shown on the watch face and 360/12 = 30).
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int col = h%6;
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From flickr

Now imagine the following situation. You are on the third floor of this building and you wish to go to the tenth. The elevator is on the fifth floor and there's an indicator that tells you where it is. Which button do you press?

Most people probably say: "press up" since they want to go up. Not long ago I watched someone do the opposite and questioned them about their behavior. They said: "well the elevator is on the fifth floor and I am on the third, so I want it to come down to me".

Much can be learnt about the design of user interfaces by considering this, apparently, simple interface. If you think about the elevator button problem you'll find that something so simple has hidden depths. How do people learn about elevator calling? What's the right amount of informati…