Image Sharpeningd3.blurd3.rankd3.flatGroup, d3.flatRollupd3.moded3.groupSortSet Operationsd3.groups as a hierarchyTime thresholds for d3.bind3.cumsumTidy Stacked Area ChartMerging Duplicate Valuesd3.zip, d3.transposed3.bind3.ticksd3.mean, d3.median, and friendsd3.quickselectd3.bisectd3.sumd3.group, d3.rollup, d3.indexd3.countd3.min, d3.max, d3.extentd3.least, d3.greatestd3.pairsd3.crossd3.ascending, d3.descendingd3.merged3.ranged3.permuted3.shuffled3-array 2.0
d3.fsum, d3.Adder
1 + 1e-14 - 1 // 🌶
d3.fsum([1, 1e-14, -1]) // 👍
d3.sum([1, -2e-17, -1]) // 🌶
d3.fsum([1, -2e-17, -1]) // 👍
d3.fsum([.1, NaN, undefined, .1, .1, .1, .1, .1, .1, .1, .1, .1])
d3.sum([.1, NaN, undefined, .1, .1, .1, .1, .1, .1, .1, .1, .1])
d3.fsum(new Set([{a: .1}, {a: .2}, {a: .3}, {a: .4}, {a: -1}]), d => d.a)
.1 + .1 + .1
d3.fsum([.1, .1, .1])
a = {
const a = new d3.Adder();
for (let i = 0; i < 3; i++) {
a.add(.01);
}
return a
}
a.valueOf()
+a // the + notation is a JavaScript shorthand notation for the valueOf method
test(d3.sum, 1000)
test(d3.fsum, 1000)
async function test(sum, delay) {
await Promises.delay(delay || 0)
const N = 10;
const t = performance.now();
for (let i = 0; i < N; i++) sum(M);
return (performance.now() - t) / N;
}
M = Float64Array.from({ length: 1e6 }, Math.random)
Purpose-built for displays of data
Observable is your go-to platform for exploring data and creating expressive data visualizations. Use reactive JavaScript notebooks for prototyping and a collaborative canvas for visual data exploration and dashboard creation.
