@rayyamhk/complex/lib/core/static/cos.js

A lightweight and easy-to-use library for you to manipulate complex numbers

"use strict";

/**
 * Calculates the cosine of a Complex Number.
 * @memberof Complex
 * @static
 * @param {Complex} num - Any Complex Number
 * @returns {Complex} The result of cosine function
 */
function cos(num) {
  if (!(num instanceof this)) {
    return this.NaN;
  }

  var a = num.getReal();
  var b = num.getImaginary();
  return new this(Math.cos(a) * Math.cosh(b), Math.sin(a) * Math.sinh(b) * -1);
}

module.exports = cos;