mathjs/src/function/arithmetic/square.js

'use strict'

const deepMap = require('../../utils/collection/deepMap')

function factory (type, config, load, typed) {
  /**
   * Compute the square of a value, `x * x`.
   * For matrices, the function is evaluated element wise.
   *
   * Syntax:
   *
   *    math.square(x)
   *
   * Examples:
   *
   *    math.square(2)           // returns number 4
   *    math.square(3)           // returns number 9
   *    math.pow(3, 2)           // returns number 9
   *    math.multiply(3, 3)      // returns number 9
   *
   *    math.square([1, 2, 3, 4])  // returns Array [1, 4, 9, 16]
   *
   * See also:
   *
   *    multiply, cube, sqrt, pow
   *
   * @param  {number | BigNumber | Fraction | Complex | Array | Matrix | Unit} x
   *            Number for which to calculate the square
   * @return {number | BigNumber | Fraction | Complex | Array | Matrix | Unit}
   *            Squared value
   */
  const square = typed('square', {
    'number': function (x) {
      return x * x
    },

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

    'BigNumber': function (x) {
      return x.times(x)
    },

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

    'Array | Matrix': function (x) {
      // deep map collection, skip zeros since square(0) = 0
      return deepMap(x, square, true)
    },

    'Unit': function (x) {
      return x.pow(2)
    }
  })

  square.toTex = { 1: `\\left(\${args[0]}\\right)^2` }

  return square
}

exports.name = 'square'
exports.factory = factory