mathjs/src/function/relational/equalScalar.js

Math.js is an extensive math library for JavaScript and Node.js. It features a flexible expression parser with support for symbolic computation, comes with a large set of built-in functions and constants, and offers an integrated solution to work with dif

'use strict'

const nearlyEqual = require('../../utils/number').nearlyEqual
const bigNearlyEqual = require('../../utils/bignumber/nearlyEqual')

function factory (type, config, load, typed) {
  /**
   * Test whether two values are equal.
   *
   * @param  {number | BigNumber | Fraction | boolean | Complex | Unit} x   First value to compare
   * @param  {number | BigNumber | Fraction | boolean | Complex} y          Second value to compare
   * @return {boolean}                                                  Returns true when the compared values are equal, else returns false
   * @private
   */
  const equalScalar = typed('equalScalar', {

    'boolean, boolean': function (x, y) {
      return x === y
    },

    'number, number': function (x, y) {
      return x === y || nearlyEqual(x, y, config.epsilon)
    },

    'BigNumber, BigNumber': function (x, y) {
      return x.eq(y) || bigNearlyEqual(x, y, config.epsilon)
    },

    'Fraction, Fraction': function (x, y) {
      return x.equals(y)
    },

    'Complex, Complex': function (x, y) {
      return x.equals(y)
    },

    'Unit, Unit': function (x, y) {
      if (!x.equalBase(y)) {
        throw new Error('Cannot compare units with different base')
      }
      return equalScalar(x.value, y.value)
    }
  })

  return equalScalar
}

exports.factory = factory