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/* eslint no-shadow: 0 */
const test = require("tap").test;const ss = require("../");
function rnd(n) {    return parseFloat(n.toFixed(4));}
// expected cumulative probabilities taken from Appendix 1, Table I of William W. Hines & Douglas C.// Montgomery, "Probability and Statistics in Engineering and Management Science", Wiley (1980).test("poissonDistribution", function (t) {    t.test(        "can return generate probability and cumulative probability distributions for lambda = 3.0",        function (t) {            t.equal("object", typeof ss.poissonDistribution(3.0));            t.equal(rnd(ss.poissonDistribution(3.0)[3]), 0.224, ss.epsilon);            t.end();        }    );    t.test(        "can generate probability and cumulative probability distributions for lambda = 4.0",        function (t) {            t.equal("object", typeof ss.poissonDistribution(4.0));            t.equal(rnd(ss.poissonDistribution(4.0)[2]), 0.1465, ss.epsilon);            t.end();        }    );    t.test(        "can generate probability and cumulative probability distributions for lambda = 5.5",        function (t) {            t.equal("object", typeof ss.poissonDistribution(5.5));            t.equal(rnd(ss.poissonDistribution(5.5)[7]), 0.1234, ss.epsilon);            t.end();        }    );    t.test(        "can generate probability and cumulative probability distributions for lambda = 9.5",        function (t) {            t.equal("object", typeof ss.poissonDistribution(9.5));            t.equal(rnd(ss.poissonDistribution(9.5)[17]), 0.0088, ss.epsilon);            t.end();        }    );    t.test("can return undefined when lambda <= 0", function (t) {        t.equal(undefined, ss.poissonDistribution(0));        t.equal(undefined, ss.poissonDistribution(-10));        t.end();    });    t.end();});