@netdata/charts/dist/es6/helpers/statistics.test.js

Netdata frontend SDK and chart utilities

import { calculateStdDev, calculateMedian, calculatePercentile, calculateAdvancedStats, calculateAllStats } from "./statistics";
describe("Statistics helpers", function () {
  var testData = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
  it("calculates standard deviation correctly", function () {
    var result = calculateStdDev(testData);
    expect(result).toBeCloseTo(2.87, 1);
  });
  it("calculates median correctly", function () {
    expect(calculateMedian(testData)).toBe(5.5);
    expect(calculateMedian([1, 2, 3])).toBe(2);
  });
  it("calculates percentiles correctly", function () {
    expect(calculatePercentile(testData, 50)).toBe(5.5);
    expect(calculatePercentile(testData, 95)).toBeCloseTo(9.55, 1);
  });
  it("calculates advanced stats", function () {
    var basicStats = {
      avg: 5.5
    };
    var result = calculateAdvancedStats(testData, basicStats);
    expect(result.median).toBe(5.5);
    expect(result.stddev).toBeCloseTo(2.87, 1);
    expect(result.p95).toBeCloseTo(9.55, 1);
    expect(result.range).toBe(9);
    expect(result.count).toBe(10);
    expect(result.volume).toBe(55);
  });
  it("calculates all stats", function () {
    var result = calculateAllStats(testData);
    expect(result.min).toBe(1);
    expect(result.max).toBe(10);
    expect(result.avg).toBe(5.5);
    expect(result.median).toBe(5.5);
    expect(result.count).toBe(10);
    expect(result.volume).toBe(55);
  });
  it("handles empty arrays", function () {
    expect(calculateStdDev([])).toBeNull();
    expect(calculateMedian([])).toBeNull();
    expect(calculatePercentile([], 50)).toBeNull();
    expect(calculateAdvancedStats([])).toEqual({});
    expect(calculateAllStats([])).toEqual({});
  });
});