mathjs/test/function/relational/compare.test.js

// test compare
var assert = require('assert'),
    math = require('../../../index'),
    error = require('../../../lib/error/index'),
    bignumber = math.bignumber,
    complex = math.complex,
    matrix = math.matrix,
    unit = math.unit,
    compare = math.compare;

describe('compare', function() {
  it('should compare two numbers correctly', function() {
    assert.equal(compare(2, 3), -1);
    assert.equal(compare(2, 2), 0);
    assert.equal(compare(2, 1), 1);
    assert.equal(compare(0, 0), 0);
    assert.equal(compare(-2, 2), -1);
    assert.equal(compare(-2, -3), 1);
    assert.equal(compare(-3, -2), -1);
  });

  it('should compare two floating point numbers correctly', function() {
    // Infinity
    assert.equal(compare(Number.POSITIVE_INFINITY, Number.POSITIVE_INFINITY), 0);
    assert.equal(compare(Number.NEGATIVE_INFINITY, Number.NEGATIVE_INFINITY), 0);
    assert.equal(compare(Number.POSITIVE_INFINITY, Number.NEGATIVE_INFINITY), 1);
    assert.equal(compare(Number.NEGATIVE_INFINITY, Number.POSITIVE_INFINITY), -1);
    assert.equal(compare(Number.POSITIVE_INFINITY, 2.0), 1);
    assert.equal(compare(2.0, Number.POSITIVE_INFINITY), -1);
    assert.equal(compare(Number.NEGATIVE_INFINITY, 2.0), -1);
    assert.equal(compare(2.0, Number.NEGATIVE_INFINITY), 1);
    // floating point numbers
    assert.equal(compare(0.3 - 0.2, 0.1), 0);
  });

  it('should compare two booleans', function() {
    assert.equal(compare(true, true), 0);
    assert.equal(compare(true, false), 1);
    assert.equal(compare(false, true), -1);
    assert.equal(compare(false, false), 0);
  });

  it('should compare mixed numbers and booleans', function() {
    assert.equal(compare(2, true), 1);
    assert.equal(compare(0, true), -1);
    assert.equal(compare(true, 2), -1);
    assert.equal(compare(false, 2), -1);
  });

  it('should compare mixed numbers and null', function() {
    assert.equal(compare(2, null), 1);
    assert.equal(compare(0, null), 0);
    assert.equal(compare(null, 2), -1);
  });

  it('should compare bignumbers', function() {
    assert.deepEqual(compare(bignumber(2), bignumber(3)), bignumber(-1));
    assert.deepEqual(compare(bignumber(2), bignumber(2)), bignumber(0));
    assert.deepEqual(compare(bignumber(3), bignumber(2)), bignumber(1));
    assert.deepEqual(compare(bignumber(0), bignumber(0)), bignumber(0));
    assert.deepEqual(compare(bignumber(-2), bignumber(2)), bignumber(-1));
  });

  it('should compare mixed numbers and bignumbers', function() {
    assert.deepEqual(compare(bignumber(2), 3), bignumber(-1));
    assert.deepEqual(compare(2, bignumber(2)), bignumber(0));
  });

  it('should compare mixed booleans and bignumbers', function() {
    assert.deepEqual(compare(bignumber(0.1), true), bignumber(-1));
    assert.deepEqual(compare(bignumber(1), true), bignumber(0));
    assert.deepEqual(compare(bignumber(1), false), bignumber(1));
    assert.deepEqual(compare(false, bignumber(0)), bignumber(0));
    assert.deepEqual(compare(true, bignumber(0)), bignumber(1));
  });

  it('should add two measures of the same unit', function() {
    assert.equal(compare(unit('100cm'), unit('10inch')), 1);
    assert.equal(compare(unit('99cm'), unit('1m')), -1);
    assert.equal(compare(unit('1m'), unit('1m')), bignumber(0));
    assert.equal(compare(unit('101cm'), unit('1m')), 1);
  });

  it('should throw an error if comparing a unit with a number', function() {
    assert.throws(function () {compare(unit('100cm'), 22)});
  });

  it('should throw an error for two measures of different units', function() {
    assert.throws(function () {compare(math.unit(5, 'km'), math.unit(100, 'gram'));});
  });

  it('should throw an error if comparing a unit with a bignumber', function() {
    assert.throws(function () {compare(unit('100cm'), bignumber(22))});
  });

  it('should perform lexical comparison for two strings', function() {
    assert.equal(compare('0', 0), 0);

    assert.equal(compare('abd', 'abc'), 1);
    assert.equal(compare('abc', 'abc'), 0);
    assert.equal(compare('abc', 'abd'), -1);
  });

  it('should compare a string an matrix elementwise', function() {
    assert.deepEqual(compare('B', ['A', 'B', 'C']), [1, 0, -1]);
    assert.deepEqual(compare(['A', 'B', 'C'], 'B'), [-1, 0, 1]);
  });

  it('should perform element-wise comparison for two matrices of same size', function() {
    assert.deepEqual(compare([1,4,6], [3,4,5]), [-1, 0, 1]);
    assert.deepEqual(compare([1,4,6], matrix([3,4,5])), matrix([-1, 0, 1]));
  });

  it('should apply configuration option epsilon', function() {
    var mymath = math.create();
    assert.equal(mymath.compare(1, 0.991), 1);
    mymath.config({epsilon: 1e-2});
    assert.equal(mymath.compare(1, 0.991), 0);
  });

  it('should throw an error when comparing complex numbers', function() {
    assert.throws(function () {compare(complex(1,1), complex(1,2))}, TypeError);
    assert.throws(function () {compare(complex(2,1), 3)}, TypeError);
    assert.throws(function () {compare(3, complex(2,4))}, TypeError);
    assert.throws(function () {compare(math.bignumber(3), complex(2,4))}, TypeError);
    assert.throws(function () {compare(complex(2,4), math.bignumber(3))}, TypeError);
  });

  it('should throw an error if matrices are different sizes', function() {
    assert.throws(function () {compare([1,4,6], [3,4])});
  });

  it('should throw an error in case of invalid number of arguments', function() {
    assert.throws(function () {compare(1)}, error.ArgumentsError);
    assert.throws(function () {compare(1, 2, 3)}, error.ArgumentsError);
  });

});