/**
  * Return the employment domain z-values for the selected city and its average
  * @param string $cityName name of the selected city
  * @return array $cityValues it contains the z-values and a z-values average
  */
 public function employmentDomain($cityName)
 {
     if (isset($cityName)) {
         if (strcmp($cityName, '') != 0) {
             $employmnet = new EmploymentController();
             //Get the z-value for  gross domestic product (GDP)
             $cityEmployment = $employmnet->cityEmployment();
             //Get the z-value for Gross value added (GVA)
             $citySalary = $employmnet->citySalary();
             $cityEmploymentInfo = array("Número de vínculos empregatícios" => $cityEmployment[$cityName], "Remuneração média" => $citySalary[$cityName]);
             $cityEmploymentValues = CityProfileController::mergeAverage($cityEmploymentInfo);
             return $cityEmploymentValues;
         }
     }
     return 0;
 }
 /**
  * It will calculate the average of the z-values for Economy
  * @return return the average of z-values by key field sortZvaluesof each city
  */
 public function employmentKeyField()
 {
     $employmnet = new EmploymentController();
     //Get the z-value for  gross domestic product (GDP)
     $cityEmployment = $employmnet->cityEmployment();
     //Get the z-value for Gross value added (GVA)
     $citySalary = $employmnet->citySalary();
     //sum z-values
     $sumZvalues = array_map(array($this, "sumCityValues"), $cityEmployment, $citySalary);
     //Divide the sum of z-values to obtain the z-values average of each city
     $zValuesAvg = array_map(array($this, "divideKeyFields"), $sumZvalues, array_fill(0, count($sumZvalues), 2));
     //combine the array keys(cities'name) with the average of z-values gotten
     $zValuesAvg = array_combine(array_keys($citySalary), array_values($zValuesAvg));
     return $zValuesAvg;
 }