MCordingley\Regression\Observation::getFeatures PHP Метод

    public function getFeatures() : array
    {
        return $this->features;
    }

 /**
  * @param Observation $observation
  * @return self
  */
 public function addObservation(Observation $observation) : self
 {
     $featureCount = count($observation->getFeatures());
     if (!$this->featureCount) {
         $this->featureCount = $featureCount;
     } elseif ($this->featureCount !== $featureCount) {
         throw new InvalidArgumentException('All observations must have the same number of features.');
     }
     $this->observations[] = $observation;
     return $this;
 }