mathjs/test/function/statistics/prod.test.js

var assert = require('assert');
var math = require('../../../index');
var BigNumber = math.type.BigNumber;
var Complex = math.type.Complex;
var DenseMatrix = math.type.DenseMatrix;
var Unit = math.type.Unit;
var prod = math.prod;

describe('prod', function() {

  it('should return the product of numbers', function() {
    assert.equal(prod(5), 5);
    assert.equal(prod(3,2), 6);
    assert.equal(prod(1,3,5,2), 30);
    assert.equal(prod(1,3,0,2), 0);
    assert.equal(prod(0,0,0,0), 0);
  });

  it('should return the product of big numbers', function() {
    assert.deepEqual(prod(new BigNumber(1),new BigNumber(3),new BigNumber(5),new BigNumber(2)),
        new BigNumber(30));
  });

  it('should return the product of complex numbers', function() {
    assert.deepEqual(prod(new Complex(2,3), new Complex(-1,2)), new Complex(-8,1));
  });

  it('should return the product of mixed numbers and complex numbers', function() {
    assert.deepEqual(prod(2, new Complex(2,3)), new Complex(4,6));
  });

  it('should return the prod from an array', function() {
    assert.equal(prod([1,3,5,2]), 30);
  });

  it('should return the prod from an 1d matrix', function() {
    assert.equal(prod(new DenseMatrix([1,3,5,2])), 30);
  });

  it('should return the prod element from a 2d array', function() {
    assert.deepEqual(prod([
      [ 1, 7, 2],
      [ 3, 5, 4]
    ]), 840);
  });

  it('should return the prod element from a 2d matrix', function() {
    assert.deepEqual(prod(new DenseMatrix([
      [ 1, 7, 2],
      [ 3, 5, 4]
    ])), 840);
  });

  it('should throw an error if called with invalid number of arguments', function() {
    assert.throws(function() {prod()});
  });

  it('should throw an error if called with not yet supported argument dim', function() {
    assert.throws(function() {prod([], 2)}, /not yet supported/);
  });

  it('should throw an error if called with an empty array', function() {
    assert.throws(function() {prod([])});
  });

  it('should LaTeX prod', function () {
    var expression = math.parse('prod(1,2,3)');
    assert.equal(expression.toTex(), '\\mathrm{prod}\\left(1,2,3\\right)');
  });

});