iframe-proxy | Sunbelt Computer Software

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import {InternMap} from "d3-array";

// Like d3.group, but takes an array of values instead of accessor, only

// supports one level of grouping, and returns an iterable of subsets of the

// given index rather than a map.

export function group(index, values) {

const groups = new InternMap();

for (const i of index) {

const value = values[i];

const group = groups.get(value);

if (group === undefined) groups.set(value, [i]);

else group.push(i);

}

return groups.values();

}

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