mathjs/src/function/logical/not.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

import { deepMap } from '../../utils/collection'
import { factory } from '../../utils/factory'
import { notNumber } from '../../plain/number'

const name = 'not'
const dependencies = ['typed']

export const createNot = /* #__PURE__ */ factory(name, dependencies, ({ typed }) => {
  /**
   * Logical `not`. Flips boolean value of a given parameter.
   * For matrices, the function is evaluated element wise.
   *
   * Syntax:
   *
   *    math.not(x)
   *
   * Examples:
   *
   *    math.not(2)      // returns false
   *    math.not(0)      // returns true
   *    math.not(true)   // returns false
   *
   *    a = [2, -7, 0]
   *    math.not(a)      // returns [false, false, true]
   *
   * See also:
   *
   *    and, or, xor
   *
   * @param  {number | BigNumber | Complex | Unit | Array | Matrix} x First value to check
   * @return {boolean | Array | Matrix}
   *            Returns true when input is a zero or empty value.
   */
  const not = typed(name, {
    number: notNumber,

    Complex: function (x) {
      return x.re === 0 && x.im === 0
    },

    BigNumber: function (x) {
      return x.isZero() || x.isNaN()
    },

    Unit: function (x) {
      return x.value !== null ? not(x.value) : true
    },

    'Array | Matrix': function (x) {
      return deepMap(x, not)
    }
  })

  return not
})