mathjs/src/function/trigonometry/sin.js

'use strict'

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

function factory (type, config, load, typed) {
  /**
   * Calculate the sine of a value.
   *
   * For matrices, the function is evaluated element wise.
   *
   * Syntax:
   *
   *    math.sin(x)
   *
   * Examples:
   *
   *    math.sin(2)                      // returns number 0.9092974268256813
   *    math.sin(math.pi / 4)            // returns number 0.7071067811865475
   *    math.sin(math.unit(90, 'deg'))   // returns number 1
   *    math.sin(math.unit(30, 'deg'))   // returns number 0.5
   *
   *    const angle = 0.2
   *    math.pow(math.sin(angle), 2) + math.pow(math.cos(angle), 2) // returns number ~1
   *
   * See also:
   *
   *    cos, tan
   *
   * @param {number | BigNumber | Complex | Unit | Array | Matrix} x  Function input
   * @return {number | BigNumber | Complex | Array | Matrix} Sine of x
   */
  const sin = typed('sin', {
    'number': Math.sin,

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

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

    'Unit': function (x) {
      if (!x.hasBase(type.Unit.BASE_UNITS.ANGLE)) {
        throw new TypeError('Unit in function sin is no angle')
      }
      return sin(x.value)
    },

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

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

  return sin
}

exports.name = 'sin'
exports.factory = factory