Published
Edited
Dec 1, 2021
2 stars
Insert cell
Insert cell
Insert cell
Insert cell
Insert cell
Insert cell
Insert cell
Insert cell
// Note that the matrix AInv, the digit set D,
// and the set of shifts F are defined below.

digraphIFS = {
let edges = [];
let eps = 0.00000001;
for (let i = 0; i < F.length; i++) {
for (let j = 0; j < F.length; j++) {
D.forEach(function (d) {
D.forEach(function (dp) {
let alpha = F[i];
let beta = F[j];
let Aalpha = math.multiply(A, alpha);
let x = Aalpha[0] + dp[0] - d[0];
let y = Aalpha[1] + dp[1] - d[1];
if (math.abs(x - beta[0]) < eps && math.abs(y - beta[1]) < eps) {
edges.push({
source: i,
target: j,
f: new AffineFunction([AInv, math.multiply(AInv, d)])
});
}
});
});
}
}
return new DigraphIFS(edges);
}
Insert cell
Insert cell
digraphIFS.dimension
Insert cell
Insert cell
digraphIFS.show_digraph()
Insert cell
Insert cell
Insert cell
digraphIFS.render_stochastic({
image_width: width < 500 ? width : 500,
n: 100000,
colors: true,
color_depth: 4
})[6]
Insert cell
Insert cell
f_invs = fs.map((af) => af.invert())
Insert cell
IFS = new IteratedFunctionSystem(fs)
Insert cell
F = [
[1, 0],
[1, 1],
[0, 1],
[-1, 0],
[-1, -1],
[0, -1]
]
Insert cell
fs = D.map((d) => new AffineFunction([AInv, math.multiply(AInv, d)]))
Insert cell
D = [
[0, 0],
[1, 0]
]
Insert cell
AInv = math.inv(A)
Insert cell
A = [
[1, 1],
[-1, 1]
]
Insert cell
// Used for pre-generated images:
//
// attractor = IFS.deterministic_path_approximation({
// init: [
// [0, 0],
// [1, -1],
// [2, 0],
// [1, 1]
// ],
// max_depth: 15
// }).flat(1)
Insert cell
Insert cell
import {
IteratedFunctionSystem,
AffineFunction,
shift,
scale,
rotate,
degree
} from "@mcmcclur/iteratedfunctionsystem-class"
Insert cell
import { DigraphIFS } from "@mcmcclur/digraphifs-class"
Insert cell
math = require("mathjs")
Insert cell

One platform to build and deploy the best data apps

Experiment and prototype by building visualizations in live JavaScript notebooks. Collaborate with your team and decide which concepts to build out.
Use Observable Framework to build data apps locally. Use data loaders to build in any language or library, including Python, SQL, and R.
Seamlessly deploy to Observable. Test before you ship, use automatic deploy-on-commit, and ensure your projects are always up-to-date.
Learn more