2b:null 2c:["$","title",null,{"children":"Crazy neighbours by delaunay | Chuncheng | Observable"}] 31:[] 2f:{"id":"21dc5bdfe35408a6","slug":"crazy-neighbours-by-delaunay","title":"Crazy neighbours by delaunay","thumbnail":"2b31c252a9fafea02740b2f6521fa2d873aa7f78933eaa2bf8bab158617d0869","access_level":"public","create_time":"$D2023-06-07T01:23:21.712Z","update_time":"$D2023-06-16T06:18:44.238Z","view_time":null,"first_public_time":"$D2023-06-07T01:23:21.712Z","fork":false,"stars":1,"starred":false,"owner":{"type":"team","id":"bcd65cef1cb4d2ed","login":"listenzcc","name":"Chuncheng","avatar_url":"https://avatars-next.observableusercontent.com/bb3c68e77a708a587ffc2d663bb83421f20d67991dbe6c1623c6e5d2fb73d15e","tier":"starter_2024"},"version":391,"publish_version":null,"role":null,"authored":false,"authors":[{"type":"individual","id":"16328058352682a8","login":"listenzcc","name":"Chuncheng","avatar_url":"https://avatars-next.observableusercontent.com/bb3c68e77a708a587ffc2d663bb83421f20d67991dbe6c1623c6e5d2fb73d15e","tier":null}],"members":[{"type":"individual","id":"16328058352682a8","login":"listenzcc","name":"Chuncheng","avatar_url":"https://avatars-next.observableusercontent.com/bb3c68e77a708a587ffc2d663bb83421f20d67991dbe6c1623c6e5d2fb73d15e","tier":null,"role":"editor"}],"comments":[],"custom_thumbnail":false,"trashed":false,"subscribed":null,"forks":1,"collection":{"id":"ff83c9236688d430","slug":"delaunay","title":"Delaunay","owner":{"id":"bcd65cef1cb4d2ed","login":"listenzcc","name":"Chuncheng"}},"type":"notebook","body":{"title":"Crazy neighbours by delaunay","cells":[{"id":0,"value":"# Crazy neighbours by delaunay\n\nThe self-organization of clustering of delaunay neighbours.","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":21,"value":"viewof button = Inputs.button(\"Refresh\")","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":34,"value":"viewof categories = Inputs.range([2, 5], {\n label: \"Categories\",\n step: 1,\n value: 3\n})","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":382,"value":"viewof neighbourOrder = Inputs.range([1, 3], {\n label: 'Neighbour order',\n step: 1,\n value: 1\n})","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":23,"value":"num = 1e4","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":187,"value":"steps = 2e2","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":101,"value":"

[Capture]

","pinned":false,"hidden":false,"mode":"html","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":112,"value":"

","pinned":false,"hidden":false,"mode":"html","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":83,"value":"{\n var j,\n count,\n targetCategory,\n capture = document.getElementById(\"capture\");\n\n for (let step = 0; step < steps; ++step) {\n count = 0;\n for (let i = 0; i < num; ++i) {\n if (isAngry(i)) {\n targetCategory = checkNeighbors(i)[0][0];\n j = rndIdx();\n while (data[j].category !== targetCategory) j = rndIdx();\n exchange(i, j);\n count += 1;\n }\n }\n\n capture.innerHTML = `\n

Step: ${step} | exchange: ${count}

\n`;\n\n yield plotDataCanvas();\n\n if (step === steps - 1 || count === 0) {\n yield plotData();\n break;\n }\n }\n\n return plotData();\n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":139,"value":"plotDataCanvas = () => {\n const canvas = document.getElementById(\"canvas\"),\n width = 800,\n height = 600,\n xScale = d3.scaleLinear().domain([0, 1]).range([0, width]).nice(),\n yScale = d3.scaleLinear().domain([1, 0]).range([0, height]).nice();\n\n canvas.setAttribute(\"width\", 800);\n canvas.setAttribute(\"height\", 600);\n\n const context = canvas.getContext(\"2d\");\n\n const r = 3;\n\n {\n context.rect(0, 0, width, height);\n context.fillStyle = \"white\";\n context.fill();\n }\n\n function drawCategory(category) {\n context.beginPath();\n data\n .filter((d) => d.category === category)\n .map((d) => {\n context.moveTo(xScale(d.x), yScale(d.y));\n context.arc(xScale(d.x), yScale(d.y), r, 0, Math.PI * 2);\n });\n\n context.fillStyle = colorScheme[category];\n context.fill();\n }\n\n for (let category = 0; category < categories; ++category) {\n drawCategory(category);\n }\n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":166,"value":"colorScheme = d3.schemeCategory10","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":32,"value":"plotData = () => {\n return Plot.plot({\n width: 800,\n height: 600,\n aspectRatio: 1.0,\n color: { legend: true, scheme: \"Category10\" },\n x: { nice: true },\n y: { nice: true },\n marks: [\n Plot.voronoi(data, {\n x: \"x\",\n y: \"y\",\n fill: \"category\",\n stroke: \"white\",\n strokeWidth: 0.3,\n opacity: 0.5\n }),\n Plot.dot(data, {\n x: \"x\",\n y: \"y\",\n fill: \"category\",\n opacity: \"movings\",\n r: 2\n }),\n Plot.frame()\n ]\n });\n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":79,"value":"/**\n * Exchange the category between i- and j-th points.\n */\nexchange = (i, j) => {\n const { category, movings } = data[i];\n\n Object.assign(data[i], { category: data[j].category, movings: movings + 1 });\n Object.assign(data[j], { category });\n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":60,"value":"/**\n * Determine if the i-the point is angry.\n * It is angry if its category is not of simple-dominance in its neighbourhood.\n */\nisAngry = (i) => {\n const neighbors = searchlight(i), // [...delaunay.neighbors(i)],\n { category } = data[i],\n others = neighbors.filter((j) => data[j].category === category);\n\n return others.length * categories < neighbors.length;\n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":345,"value":"/**\n * Search the i-th point for its neighbours,\n * it is a searchlight method.\n */\nsearchlight = (idx, order = neighbourOrder) => {\n var neighbours = [idx],\n edge = [idx],\n newEdge;\n\n for (let i = 0; i < order; ++i) {\n newEdge = [];\n edge.map((j) => {\n newEdge = newEdge.concat([...delaunay.neighbors(j)]);\n });\n\n edge = newEdge.filter((d) => neighbours.indexOf(d) < 0);\n\n neighbours = neighbours.concat(newEdge);\n }\n\n return [...new Set(neighbours)].filter((d) => d !== idx);\n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":363,"value":"searchlight(0)","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":351,"value":"[...new Set([1, 1, 3].concat([4, 5]))]","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":243,"value":"checkNeighbors(0)","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":213,"value":"/**\n * Checkout the neighbours of the i-th point,\n * the neighbours are grouped by their category,\n * and the counts are used to sort the categories.\n */\ncheckNeighbors = (i) =>\n [...d3.group(searchlight(i), (d) => data[d].category)].sort(\n (a, b) => b[1].length - a[1].length\n )","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":63,"value":"delaunay = d3.Delaunay.from(data.map((d) => [d.x, d.y]))","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":19,"value":"data = {\n button;\n // neighbourOrder;\n\n const data = [];\n\n for (let i = 0; i < num; ++i) {\n data.push(generatePnt(i));\n }\n\n return data;\n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":43,"value":"data","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":17,"value":"/**\n * Generate random point\n */\ngeneratePnt = (i = 0) => {\n const x = rnd(),\n y = rnd(),\n category = rndCategory(),\n movings = 0;\n\n return { i, x, y, category, movings };\n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":15,"value":"dist = (a, b) => {\n return Math.sqrt(Math.pow(a.x - b.x, 2) + Math.pow(a.y - b.y, 2));\n}","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":57,"value":"rndIdx = d3.randomInt(num)","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":41,"value":"rndCategory = d3.randomInt(categories)","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":13,"value":"rnd = d3.randomUniform(0, 1)","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":11,"value":"d3 = require(\"d3\")","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"}],"files":"$W31","stdlib":"1","titling":"auto"}} 30:"$2f:body"