public function trained() : bool
    {
        return ($this->estimator instanceof Learner
            and $this->estimator->trained() and $this->fitted)
            or $this->fitted;
    }
public function trained() : bool
    {
        return ($this->estimator instanceof Learner
            and $this->estimator->trained() and $this->fitted)
            or $this->fitted;
    }
public function trained ( ) : bool { return ( $ this -> estimator instanceof Learner and $ this -> estimator -> trained ( ) and $ this -> fitted ) or $ this -> fitted ; }
Has the learner been trained?

@return bool
Has the learner been trained?