Files
cellxgene/client/src/util/quantile.js
T

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772 B
JavaScript

/*
quantiles - calculate quantiles for the typed array.
Currently interpolates to 'lower' value.
Arguments:
* quantArr - array of quantiles to compute, where values: 0 <= value <= 1.0
* tarr - a typed array
* sorted - option bool. If false (default), will assume array is not sorted.
If true, will assume it is sorted.
*/
import { sortArray } from "./typedCrossfilter/sort";
export default function quantile(quantArr, tarr, sorted = false) {
/*
start with the naive (sort) implementation. Later, use a faster partition
*/
const arr = sorted ? tarr : sortArray(new tarr.constructor(tarr)); // copy
const len = arr.length;
return quantArr.map((q) => {
if (q === 1) {
return arr[len - 1];
}
return arr[Math.floor(q * len)];
});
}