mathjs/src/function/arithmetic/ceil.js

'use strict'

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

function factory (type, config, load, typed) {
  const round = load(require('../../function/arithmetic/round'))

  /**
   * Round a value towards plus infinity
   * If `x` is complex, both real and imaginary part are rounded towards plus infinity.
   * For matrices, the function is evaluated element wise.
   *
   * Syntax:
   *
   *    math.ceil(x)
   *
   * Examples:
   *
   *    math.ceil(3.2)               // returns number 4
   *    math.ceil(3.8)               // returns number 4
   *    math.ceil(-4.2)              // returns number -4
   *    math.ceil(-4.7)              // returns number -4
   *
   *    const c = math.complex(3.2, -2.7)
   *    math.ceil(c)                 // returns Complex 4 - 2i
   *
   *    math.ceil([3.2, 3.8, -4.7])  // returns Array [4, 4, -4]
   *
   * See also:
   *
   *    floor, fix, round
   *
   * @param  {number | BigNumber | Fraction | Complex | Array | Matrix} x  Number to be rounded
   * @return {number | BigNumber | Fraction | Complex | Array | Matrix} Rounded value
   */
  const ceil = typed('ceil', {
    'number': function (x) {
      if (nearlyEqual(x, round(x), config.epsilon)) {
        return round(x)
      } else {
        return Math.ceil(x)
      }
    },

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

    'BigNumber': function (x) {
      if (bigNearlyEqual(x, round(x), config.epsilon)) {
        return round(x)
      } else {
        return x.ceil()
      }
    },

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

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

  ceil.toTex = { 1: `\\left\\lceil\${args[0]}\\right\\rceil` }

  return ceil
}

exports.name = 'ceil'
exports.factory = factory