tests_math_stats.test.js

import {describe, test, assert} from 'vitest';
import {
  getStats,
  getBasicStats,
  guid
} from '../../src/math/stats.js';

/**
 * Tests for the 'math/stats.js' file.
 */

describe('math', () => {

  /**
   * Tests for {@link getBasicStats}.
   *
   * @function module:tests/math~getbasicstats
   */
  test('getBasicStats', () => {
    const arr0 = [1, 2, 3, 4, 5];
    const q0 = getBasicStats(arr0);
    // min
    assert.equal(q0.min, 1, 'min.0');
    // max
    assert.equal(q0.max, 5, 'max.0');
    // mean
    assert.equal(q0.mean, 3, 'mean.0');
    // stdDev
    assert.equal(q0.stdDev, 1.4142135623730951, 'stdDev.0');

    /* eslint-disable @stylistic/js/array-element-newline */
    const arr1 = [
      9, 2, 5, 4,
      12, 7, 8, 11,
      9, 3, 7, 4,
      12, 5, 4, 10,
      9, 6, 9, 4
    ];
    /* eslint-enable @stylistic/js/array-element-newline */
    const q1 = getBasicStats(arr1);
    // min
    assert.equal(q1.min, 2, 'min.1');
    // max
    assert.equal(q1.max, 12, 'max.1');
    // mean
    assert.equal(q1.mean, 7, 'mean.1');
    // stdDev
    assert.equal(q1.stdDev, 2.9832867780352594, 'stdDev.1');
  });

  /**
   * Tests for {@link getFullStats}.
   *
   * @function module:tests/math~getfullstats
   */
  test('getFullStats', () => {
    const arr0 = [15, 20, 35, 40, 50];
    const q0 = getStats(arr0, ['median']);
    // median
    assert.equal(q0.median, 35, 'median.0');
    // p25
    assert.equal(q0.p25, 20, 'p25.0');
    // p75
    assert.equal(q0.p75, 40, 'p75.0');

    const arr1 = [15, 20, 35, 40, 50, 60];
    const q1 = getStats(arr1, ['median']);
    // median
    assert.equal(q1.median, 37.5, 'median.1');
    // p25
    assert.equal(q1.p25, 23.75, 'p25.1');
    // p75
    assert.equal(q1.p75, 47.5, 'p75.1');
  });

  /**
   * Tests for {@link guid}.
   *
   * @function module:tests/math~guid
   */
  test('GUID', () => {
    const id0 = guid();
    const id1 = guid();
    assert.equal((id0 === id1), false, 'Two GUids should not be equal.');

    let duplicates = 0;
    // create an array of guids
    const ids = [];
    for (let i = 0; i < 1000; ++i) {
      ids[ids.length] = guid();
    }
    // check duplicates
    let id = 0;
    for (let i = 0; i < ids.length - 1; ++i) {
      id = ids.pop();
      if (ids.indexOf(id) !== -1) {
        ++duplicates;
      }
    }
    assert.equal(duplicates, 0, '1000 GUids should not be equal.');
  });

});