frontend + d3
Published
Edited
Nov 7, 2020
1 star
chart = {
// init
const svg = d3.create('svg');
const g = svg.append('g');
// prepare arrows
const markerBoxWidth = 20;
const markerBoxHeight = 20;
const refX = markerBoxWidth / 2;
const refY = markerBoxHeight / 2;
svg
.append('defs')
.append('marker')
.attr('id', 'arrow')
.attr('viewBox', [0, 0, markerBoxWidth, markerBoxHeight])
.attr('refX', refX)
.attr('refY', refY)
.attr('markerWidth', markerBoxWidth)
.attr('markerHeight', markerBoxHeight)
.attr('orient', 'auto-start-reverse')
.append('path')
.attr('d', d3.line()(arrowPoints))
.attr('stroke', 'black')
.attr('opacity', .3);
svg.call(size, () => [width, config.height]);
g.call(trans, () => [config.margin, config.margin]);
const enterCircle = node =>
node
.append('circle')
.attr('r', config.radius)
.attr('fill', d => colorScale(d.id));
const enterText = node =>
node
.append('text')
.text(d => d.id)
.attr('alignment-baseline', 'middle')
.attr('text-anchor', 'middle')
.attr('font-family', 'sans-serif')
.attr('font-size', '10px');
const enterNode = node =>
node
.append('g')
.attr('class', 'spot')
.attr('data-id', d => d.id)
.call(enterCircle)
.call(enterText);
const updateNode = node => node.call(trans, d => [scaleX(d.x), scaleY(d.y)]);
const lineGen = d3.line();
const enterLink = link =>
link
.append('path')
.attr('stroke', 'black')
.attr('marker-end', 'url(#arrow)')
.attr('opacity', .3)
.call(updateLink);
const updateLink = link =>
link.attr('d', d => {
const sourceLoc = [scaleX(d.sourceData.x), scaleY(d.sourceData.y)];
const targetLoc = [scaleX(d.targetData.x), scaleY(d.targetData.y)];
return lineGen([sourceLoc, targetLoc]);
});
function render(_data, _links) {
const xExtent = d3.extent(_data.map(d => d.x));
const yExtent = d3.extent(_data.map(d => d.y));
// console.log(xExtent, yExtent);
scaleX.domain(xExtent).range([0, width - config.margin]);
scaleY.domain(yExtent).range([0, config.height - config.margin * 2]);
const nodes = g
.selectAll('.spot')
.data(_data)
.join(enterNode, updateNode);
const dataById = getDataById(_data);
// const compositeLinks = _links.map(l => {
// const sourceData = dataById.get(l.source) || [{ x: 0, y: 0 }];
// const targetData = dataById.get(l.target) || [{ x: 0, y: 0 }];
// return { ...l, sourceData: sourceData[0], targetData: targetData[0] };
// });
const compositeLinks = _links.map(l => {
return { ...l, sourceData: l.source, targetData: l.target };
});
console.log(compositeLinks);
const links = g
.selectAll('path')
.data(compositeLinks)
.join(enterLink, updateLink);
}
return Object.assign(svg.node(), { render });
}
chart.render(data, links)
simulation = d3
.forceSimulation()
.nodes(data)
.force('charge', d3.forceManyBody())
.force(
'link',
d3
.forceLink()
.links(links)
.id(d => d.id)
)
.on('tick', () => {
chart.render(data, links);
})
data = [
{ id: 'spot1' },
{ id: 'spot2' },
{ id: 'spot3' },
{ id: 'spot4' },
{ id: 'spot5' },
{ id: 'spot6' }
]
sampleDataById = d3.group(data, d => d.id)
getDataById = _data => d3.group(_data, d => d.id)
links = [
{ source: 'spot1', target: 'spot2' },
{ source: 'spot2', target: 'spot3' },
{ source: 'spot3', target: 'spot4' },
]
scaleX = d3.scaleLinear()
scaleY = d3.scaleLinear()
config = ({
margin: 50,
height: 300,
radius: 20
})
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.