31:T737,chart = { const svg = d3.create("svg") .attr("viewBox", [-width / 2, -height / 2, width, height]); const simulation = d3.forceSimulation() .force("charge", d3.forceManyBody().strength(-3000)) .force("link", d3.forceLink().id(d => d.id).distance(20)) .force("x", d3.forceX()) .force("y", d3.forceY()) .on("tick", ticked); let link = svg.append("g") .attr("stroke", "#000") .attr("stroke-width", 1.5) .selectAll("line"); let node = svg.append("g") .attr("stroke", "#fff") .attr("stroke-width", 1.5) .selectAll("circle") // lets the user drag around nodes .call(drag(simulation)); function ticked() { node.attr("cx", d => d.x) .attr("cy", d => d.y) .attr("fill", d => color(d.id)) link.attr("x1", d => d.source.x) .attr("y1", d => d.source.y) .attr("x2", d => d.target.x) .attr("y2", d => d.target.y); } // Terminate the force layout when this cell re-runs. invalidation.then(() => simulation.stop()); return Object.assign(svg.node(), { update({nodes, links}) { // Make a shallow copy to protect against mutation, while // recycling old nodes to preserve position and velocity. const old = new Map(node.data().map(d => [d.id, d])); nodes = nodes.map(d => Object.assign(old.get(d.id) || {}, d)); links = links.map(d => Object.assign({}, d)); node = node .data(nodes, d => d.id) .join(enter => enter.append("circle") .attr("r", 20) .attr("fill", d => color(d))) .call(drag(simulation)); link = link .data(links, d => [d.source, d.target]) .join("line"); simulation.nodes(nodes); simulation.force("link").links(links); simulation.alpha(1).restart(); } }); }32:[] 2f:{"title":"Updating Graph Nodes and Edges","cells":[{"id":1,"value":"md`# Updating Graph Nodes and Edges`","pinned":false,"hidden":false,"mode":"ojs"},{"id":198,"value":"viewof graph = {\n const form = html``;\n const graphs = {1: graph1, 2: graph2, 3: graph3};\n form.onchange = () => form.dispatchEvent(new CustomEvent(\"input\")); // Safari\n form.oninput = event => { \n form.value = graphs[form.radio.value];\n };\n form.value = graphs[form.radio.value];\n return form;\n}","pinned":false,"hidden":false,"mode":"ojs"},{"id":7,"value":"$31","pinned":true,"hidden":false,"mode":"ojs"},{"id":191,"value":"update = chart.update(graph)","pinned":true,"hidden":false,"mode":"ojs"},{"id":150,"value":"graph1 = ({\n nodes: [\n {id: 1},\n {id: 2},\n {id: 3},\n {id: 4},\n {id: 5},\n {id: 6}\n ], \n links: [\n {source: 1, target: 5},\n {source: 4, target: 5},\n {source: 4, target: 6},\n {source: 3, target: 2},\n {source: 5, target: 2},\n {source: 1, target: 2},\n {source: 3, target: 4}\n ]\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":164,"value":"graph2 = ({\n nodes: [\n {id: 1},\n {id: 2},\n {id: 3},\n {id: 4}\n ], \n links: [\n {source: 3, target: 2},\n {source: 1, target: 2},\n {source: 3, target: 4},\n {source: 2, target: 4},\n ]\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":195,"value":"graph3 = ({\n nodes: [\n {id: \"a\"},\n {id: \"b\"}\n ],\n links: [\n {source: \"a\", target: \"b\"}\n ]\n})","pinned":true,"hidden":false,"mode":"ojs"},{"id":32,"value":"height = 600","pinned":true,"hidden":false,"mode":"ojs"},{"id":26,"value":"color = d3.scaleOrdinal(d3.schemeTableau10)","pinned":true,"hidden":false,"mode":"ojs"},{"id":76,"value":"drag = simulation => {\n \n function dragstarted(event) {\n if (!event.active) simulation.alphaTarget(0.3).restart();\n event.subject.fx = event.subject.x;\n event.subject.fy = event.subject.y;\n }\n \n function dragged(event) {\n event.subject.fx = event.x;\n event.subject.fy = event.y;\n }\n \n function dragended(event) {\n if (!event.active) simulation.alphaTarget(0);\n event.subject.fx = null;\n event.subject.fy = null;\n }\n \n return d3.drag()\n .on(\"start\", dragstarted)\n .on(\"drag\", dragged)\n .on(\"end\", dragended);\n}","pinned":true,"hidden":false,"mode":"ojs"},{"id":11,"value":"d3 = require(\"d3@6\")","pinned":true,"hidden":false,"mode":"ojs"}],"files":"$W32","stdlib":"1","titling":"auto"}