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/* eslint no-shadow: 0 */
const test = require("tap").test;const ss = require("../dist/simple-statistics.js");
test("sample skewness", function (t) {    t.test("the skewness of an empty sample is null", function (t) {        const data = [];        t.throws(function () {            ss.sampleSkewness(data);        });        t.end();    });
    t.test("the skewness of an sample with one number is null", function (t) {        const data = [1];        t.throws(function () {            ss.sampleSkewness(data);        });        t.end();    });
    t.test("the skewness of an sample with two numbers is null", function (t) {        const data = [1, 2];        t.throws(function () {            ss.sampleSkewness(data);        });        t.end();    });
    t.test("can calculate the skewness of SAS example 1", function (t) {        // Data and answer taken from SKEWNESS function documentation at        // http://support.sas.com/documentation/c../lrdict/64316/HTML/default/viewer.htm#a000245947.htm        const data = [0, 1, 1];        t.equal(+ss.sampleSkewness(data).toPrecision(10), -1.732050808);        t.end();    });
    t.test("can calculate the skewness of SAS example 2", function (t) {        // Data and answer taken from SKEWNESS function documentation at        // http://support.sas.com/documentation/c../lrdict/64316/HTML/default/viewer.htm#a000245947.htm        const data = [2, 4, 6, 3, 1];        t.equal(+ss.sampleSkewness(data).toPrecision(10), 0.5901286564);        t.end();    });
    t.test("can calculate the skewness of SAS example 3", function (t) {        // Data and answer taken from SKEWNESS function documentation at        // http://support.sas.com/documentation/c../lrdict/64316/HTML/default/viewer.htm#a000245947.htm        const data = [2, 0, 0];        t.equal(+ss.sampleSkewness(data).toPrecision(10), 1.732050808);        t.end();    });    t.end();});