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/* eslint no-shadow: 0 */
const test = require("tap").test;const ss = require("../");
function rnd(x) {    return Math.round(x * 1000) / 1000;}
test("sample variance", function (t) {    t.test("can get the sample variance of a six-sided die", function (t) {        t.equal(rnd(ss.sampleVariance([1, 2, 3, 4, 5, 6])), 3.5);        t.end();    });
    // confirmed in R    //    // > var(1:10)    // [1] 9.166667    t.test("can get the sample variance of numbers 1-10", function (t) {        t.equal(rnd(ss.sampleVariance([1, 2, 3, 4, 5, 6, 7, 8, 9, 10])), 9.167);        t.end();    });
    t.test(        "the sample variance of two numbers that are the same is 0",        function (t) {            t.equal(rnd(ss.sampleVariance([1, 1])), 0);            t.end();        }    );
    t.throws(function () {        ss.sampleVariance([1]);    }, "the sample variance of one number cannot be calculated");
    t.throws(function () {        ss.sampleVariance([]);    }, "the sample variance of no numbers cannot be calculated");
    t.end();});