code: function() {
  
        var tmp = Math.exp(this['re']);
  
        if (this['im'] === 0) {
          //return new Complex(tmp, 0);
        }
        return new Complex(
                tmp * Math.cos(this['im']),
                tmp * Math.sin(this['im']));
      }
docs: Calculate the complex exponent
  
  @returns {Complex}