@aikidosec/firewall/helpers/percentiles.js

Zen by Aikido is an embedded Application Firewall that autonomously protects Node.js apps against common and critical attacks, provides rate limiting, detects malicious traffic (including bots), and more.

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.percentiles = percentiles;
function percentiles(percentiles, list) {
    if (list.length === 0) {
        throw new Error("List should not be empty");
    }
    percentiles.forEach((p) => {
        if (p < 0) {
            throw new Error(`Expect percentile to be >= 0 but given "${p}" and its type is "${typeof p}".`);
        }
        if (p > 100) {
            throw new Error(`Expect percentile to be <= 100 but given "${p}" and its type is "${typeof p}".`);
        }
    });
    const sortedList = Array.from(list).sort((a, b) => a - b);
    return percentiles.map((p) => getPercentileValue(p, sortedList));
}
function getPercentileValue(p, list) {
    if (p === 0) {
        return list[0];
    }
    const kIndex = Math.ceil(list.length * (p / 100)) - 1;
    return list[kIndex];
}