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

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

"use strict";

/**
 * Calculates the natural log of the Complex Number.<br><br>
 * 
 * Note that complex log is a multivalued function,
 * and this function only provides the principal value by
 * restricting the imaginary part to the interval [0, 2π).
 * @memberof Complex
 * @static
 * @param {Complex} num - Complex Number
 * @returns {number} Natural log of the Complex Number
 */
function log(num) {
  if (!(num instanceof this)) {
    return this.NaN;
  }

  var r = num.getModulus();
  var theta = num.getArgument();

  if (r < this.EPSILON || theta === undefined) {
    return this.NaN;
  }

  return new this(Math.log(r), theta);
}

module.exports = log;