A field guide, on the web
A guided journey through fractal geometry — from recursion and fractional dimension to classic constructions, complex dynamics, and code. Explore the history, the rule at the heart of each exhibit, with complete, runnable implementations in Python and Haskell.
Your route through the fair
What fractals actually are, the century of mathematicians who discovered them piece by piece, and the three distinct mechanisms — IFS, L-systems, and escape-time iteration — every chapter that follows is built from.
Before meeting the famous fractals, learn the two ideas that make most of them possible: repeat a rule, and watch structure reappear across scales.
What could 1.585-dimensional possibly mean? Fractal dimension turns that apparently absurd question into a calculation.
The simplest fractal in this book: remove the middle third, forever, and end up with a set that is simultaneously almost nothing and just as big as everything.
Two routes to the same triangle: a random walk that jumps toward a random vertex forever, or simply removing the middle triangle, recursively. The figure uses the second — true vector triangles, crisp at any zoom.
A curve of infinite length enclosing a finite area — one segment becomes four, forever.
Fold a strip of paper in half, again and again, then unfold every crease to a right angle — that's the whole construction.
A biologist's model of algae growth turns out to be the cleanest possible generalisation of the Koch and dragon constructions.
Four affine maps and a handful of probabilities encode something that looks uncannily like a real frond.
The first published space-filling curve — a 1-D line whose image is a full 2-D square.
A cleaner space-filling curve than Peano's, and — unlike Peano's — one with real engineering applications.
A local, deterministic root-finder — yet the global picture of which root it converges to is a fractal.
Fix the parameter, vary the starting point — the mirror image of the Mandelbrot construction next door.
The index of every Julia set at once — and the most recognisable image in popular mathematics.
Every figure on this site was generated by open, runnable source
code — nothing is hand-drawn. Each chapter pairs a Python
reference implementation (NumPy + Matplotlib) with an idiomatic
Haskell companion using the diagrams EDSL, shown
side by side so the fractal's definition and its code stay in
view together.
For book and paper recommendations on where to go deeper, see the Further Reading page.