The Old Joel on Software Forum: Part 3 (of 5) - Sybase Logo. What math function is it called?

Sybase Logo. What math function is it called?

Bella
Saturday, November 1, 2003

It looks kind of like the illustration of the Golden Ratio: http://mathworld.wolfram.com/GoldenRectangle.html

anon
Saturday, November 1, 2003

I'd say more that kinda.

B#
Saturday, November 1, 2003

Specifically, it's a logarithmic spiral.

anon
Saturday, November 1, 2003

It's usually referred to as the Golden Spiral in my experience.

*monad
Saturday, November 1, 2003

It's called a fractal.

http://www.cs.berkeley.edu/~ddgarcia/ucbugg/Sp2001Fractal.pdf

Realist
Saturday, November 1, 2003

If memory serves, it's the same spiral as the Nautilus shell. It's built by putting squares next to each other, following the fibonacci sequence:

x(n) = x(n-1) + x(n-2)

whose first few digits are

1 1 2 3 5 8 13 21

So: take a square with length 1, stick a square with length 1 next to it, then a square with length 2, 3, 5, etc. Do this clockwise or counterclockwise.

Then you draw quarter circles going through opposite corners of each of these squares.

If you look at the logo, the two smallest inner squares have length 1, the one above it 2, the one to the left 3, the one beneath 5

Yves
Sunday, November 2, 2003

Ok, what does this logo have to do with relational databases?

anon
Sunday, November 2, 2003

It's called an Archimedes Spiral.

Claw
Monday, November 3, 2003

Sorry... I take back my comment above. I was thinking of the wrong spiral. It's actually a logarithmic spiral.

Claw
Monday, November 3, 2003

It is *almost* a logarithmic spiral...

The sprial as shown is composed of circle segments. Each circle segment is a quarter of a circle, with the centre of the circle being placed in one of the corners of the square.

Karel Thönissen
Monday, November 3, 2003

Oops, I should read before posting. The correct answer is on the page. I stand corrected.

Karel Thönissen
Monday, November 3, 2003

You *don't* get exactly a logarithmic spiral by putting together Fibonacci-sized squares, though after the first few squares are in place it's pretty close. The Sybase logo looks to me as if it is made from Fibonacci-sized squares, except that the two 1s have lost the line dividing them.

A logarithmic spiral inscribed in a golden rectangle divided into squares doesn't exactly touch the sides, but the spiral in the Sybase logo is tangent to the sides at the corner points.

So, on at least two different grounds, the Sybase logo appears not to be exactly a logarithmic spiral. But it's pretty close.

A logarithmic spiral is not a fractal. I don't think the supporting pattern of rectangles is a fractal either, but I haven't checked.

If you google for "spiral site:sybase.com" you'll find some blather from some senior person at Sybase about what it's supposed to symbolize.

Gareth McCaughan
Monday, November 3, 2003