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/* eslint no-shadow: 0 */
const test = require("tap").test;const ss = require("../dist/simple-statistics.js");
// Force shuffling to return the first points in the array to ensure// reproducibility of tests. This works because of the way the Fisher-Yates// shuffle selects array elements via multiplication and flooring.function nonRNG() {    return 1.0 - ss.epsilon;}
test("k-means clustering test", function (t) {    t.test(        "Single cluster of one point contains only that point",        function (t) {            const points = [[0.5]];            const { labels, centroids } = ss.kMeansCluster(points, 1, nonRNG);            t.same(labels, [0]);            t.same(centroids, [[0.5]]);            t.end();        }    );
    t.test("Single cluster of two points contains both points", function (t) {        const points = [[0.0], [1.0]];        const { labels, centroids } = ss.kMeansCluster(points, 1, nonRNG);        t.same(labels, [0, 0]);        t.same(centroids, [[0.5]]);        t.end();    });
    t.test(        "Two clusters of two points puts each point in its own cluster",        function (t) {            const points = [[0.0], [1.0]];            const { labels, centroids } = ss.kMeansCluster(points, 2, nonRNG);            t.same(labels, [0, 1]);            t.same(centroids, [[0.0], [1.0]]);            t.end();        }    );
    t.test(        "Two clusters of four paired points puts each pair in a cluster",        function (t) {            const points = [[0.0], [1.0], [0.0], [1.0]];            const { labels, centroids } = ss.kMeansCluster(points, 2, nonRNG);            t.same(labels, [0, 1, 0, 1]);            t.same(centroids, [[0.0], [1.0]]);            t.end();        }    );
    t.test(        "Two clusters of two 2D points puts each point in its own cluster",        function (t) {            const points = [                [0.0, 0.5],                [1.0, 0.5]            ];            const { labels, centroids } = ss.kMeansCluster(points, 2, nonRNG);            t.same(labels, [0, 1]);            t.same(centroids, [                [0.0, 0.5],                [1.0, 0.5]            ]);            t.end();        }    );
    t.test("Base case of one value", function (t) {        t.throws(() => {            ss.kMeansCluster([1], 2, nonRNG);        });        t.end();    });
    t.test(        "Two clusters of three 2D points puts two points in one cluster and one in the other",        function (t) {            const points = [                [0.0, 0.5],                [1.0, 0.5],                [0.1, 0.0]            ];            const { labels, centroids } = ss.kMeansCluster(points, 2, nonRNG);            t.same(labels, [0, 1, 0]);            t.same(centroids, [                [0.05, 0.25],                [1.0, 0.5]            ]);            t.end();        }    );
    t.end();});