@technobuddha/library/src/mersenne-twister.test.ts

A large library of useful functions

import { MersenneTwister } from './mersenne-twister.ts';

describe('MersenneTwister', () => {
  test('should generate same random int32 from seed', () => {
    const mt = new MersenneTwister(0);

    expect(mt.genrandInt32()).toBe(293910048);
    expect(mt.genrandInt32()).toBe(417317171);
    expect(mt.genrandInt32()).toBe(2036186861);
    expect(mt.genrandInt32()).toBe(1160412725);
    expect(mt.genrandInt32()).toBe(338713629);
    expect(mt.genrandInt32()).toBe(1008941840);
  });

  test('should generate same random int31 from seed', () => {
    const mt = new MersenneTwister(0);

    expect(mt.genrandInt31()).toBe(146955024);
    expect(mt.genrandInt31()).toBe(208658585);
    expect(mt.genrandInt31()).toBe(1018093430);
    expect(mt.genrandInt31()).toBe(580206362);
    expect(mt.genrandInt31()).toBe(169356814);
    expect(mt.genrandInt31()).toBe(504470920);
  });

  test('should generate same random real1 from seed', () => {
    const mt = new MersenneTwister(0);

    expect(mt.genrandReal1()).toBeCloseTo(0.0684312656681126, 15);
    expect(mt.genrandReal1()).toBeCloseTo(0.0971642255543647, 15);
    expect(mt.genrandReal1()).toBeCloseTo(0.4740866975565643, 15);
    expect(mt.genrandReal1()).toBeCloseTo(0.2701796417287969, 15);
    expect(mt.genrandReal1()).toBeCloseTo(0.0788629122727697, 15);
    expect(mt.genrandReal1()).toBeCloseTo(0.2349125780712144, 15);
  });

  test('should generate same random real2 from seed', () => {
    const mt = new MersenneTwister(0);

    expect(mt.genrandReal2()).toBeCloseTo(0.0684312656521797, 15);
    expect(mt.genrandReal2()).toBeCloseTo(0.0971642255317419, 15);
    expect(mt.genrandReal2()).toBeCloseTo(0.4740866974461823, 15);
    expect(mt.genrandReal2()).toBeCloseTo(0.2701796416658908, 15);
    expect(mt.genrandReal2()).toBeCloseTo(0.078862912254408, 15);
    expect(mt.genrandReal2()).toBeCloseTo(0.2349125780165195, 15);
  });

  test('should generate same random real3 from seed', () => {
    const mt = new MersenneTwister(0);

    expect(mt.genrandReal3()).toBeCloseTo(0.068431265768595, 15);
    expect(mt.genrandReal3()).toBeCloseTo(0.0971642256481573, 15);
    expect(mt.genrandReal3()).toBeCloseTo(0.4740866975625977, 15);
    expect(mt.genrandReal3()).toBeCloseTo(0.2701796417823061, 15);
    expect(mt.genrandReal3()).toBeCloseTo(0.0788629123708233, 15);
    expect(mt.genrandReal3()).toBeCloseTo(0.2349125781329348, 15);
  });

  test('should generate same random res53 from seed', () => {
    const mt = new MersenneTwister(0);

    expect(mt.genrandRes53()).toBeCloseTo(0.0684312663761095, 15);
    expect(mt.genrandRes53()).toBeCloseTo(0.4740866964323791, 15);
    expect(mt.genrandRes53()).toBeCloseTo(0.0788629072525544, 15);
    expect(mt.genrandRes53()).toBeCloseTo(0.287578644146807, 15);
    expect(mt.genrandRes53()).toBeCloseTo(0.2310116773870166, 15);
    expect(mt.genrandRes53()).toBeCloseTo(0.0952395144272963, 15);
  });

  test('should generate same random int32 from array seed', () => {
    const mt = new MersenneTwister(Array.from({ length: 100 }).fill(0) as number[]);

    expect(mt.genrandInt32()).toBe(1434223582);
    expect(mt.genrandInt32()).toBe(1450191270);
  });

  test('should generate same random int31 from array seed', () => {
    const mt = new MersenneTwister(Array.from({ length: 1000 }).fill(0) as number[]);

    expect(mt.genrandInt32()).toBe(1914342825);
    expect(mt.genrandInt32()).toBe(305667567);
  });

  test('should generate random int32', () => {
    const mt = new MersenneTwister();

    expect(mt.genrandInt32()).toBeLessThanOrEqual(0xffffffff);
  });
});