Image Sharpeningd3.blurd3.rankd3.flatGroup, d3.flatRollupd3.moded3.groupSortSet Operationsd3.groups as a hierarchyd3.fsum, d3.AdderTime thresholds for d3.bind3.cumsumTidy Stacked Area Chartd3.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
Merging Duplicate Values
data = [
{name: "Jan", value: 15},
{name: "Feb", value: 7},
{name: "Mar", value: 3},
{name: "Apr", value: 10},
{name: "May", value: 15},
{name: "May", value: 9},
{name: "Jun", value: 15},
{name: "Jul", value: 0},
{name: "Aug", value: 0},
{name: "Sep", value: 0},
{name: "Oct", value: 0},
{name: "Nov", value: 0},
{name: "Dec", value: 0}
]
d3.group(data, d => d.name)
d3.rollup(data, g => d3.sum(g, d => d.value), d => d.name)
d3.rollup(data, g => g.reduce((p, v) => (p.value += v.value, p), {...g[0], value: 0}), d => d.name)
d3.rollup(
data,
group => {
const reduce = {...group[0], value: 0};
for (const {value} of group) {
reduce.value += value;
}
return reduce;
},
d => d.name
)
Array.from(d3.rollup(data, g => g.reduce((p, v) => (p.value += v.value, p), {...g[0], value: 0}), d => d.name).values())
Array.from(d3.group(data, d => d.name), ([name, group]) => ({name, value: d3.sum(group, d => d.value)}))
d3.groups(data, d => d.name).map(([name, group]) => ({name, value: d3.sum(group, d => d.value)}))
d3 = require("d3-array@2")
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.
